5 People Who Claim to be Time Travelers

Is time travel possible?

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If you can time travel, please tell Stephen Hawking we said hi.

Is time travel possible? Short answer: Yes, and you’re doing it right now — hurtling into the future at the impressive rate of one second per second. You’re pretty much always moving through time at the same speed, whether you’re watching paint dry or wishing you had more hours to visit with a friend from out of town. 

But this isn’t the kind of time travel that’s captivated countless science fiction writers, or spurred a genre so extensive that Wikipedia lists nearly 400 titles in the category “Movies about Time Travel.” In franchises like “Doctor Who,” “Star Trek,” and “Back to the Future” characters climb into some wild vehicle to blast into the past or spin into the future. Once the characters have traveled through time, they grapple with what happens if you change the past or present based on information from the future (which is where time travel stories intersect with the idea of parallel universes or alternate timelines). 

Although many people are fascinated by the idea of changing the past or seeing the future before it’s due, no person has ever demonstrated the kind of back-and-forth time travel seen in science fiction, or proposed a method of sending a person through significant periods of time that wouldn’t destroy them on the way. And, as physicist Stephen Hawking pointed out in his book “Black Holes and Baby Universes” (Bantam, 1994), “The best evidence we have that time travel is not possible, and never will be, is that we have not been invaded by hordes of tourists from the future.”Click here for more Space.com videos…

Science does support some amount of time-bending, though. For example, physicist Albert Einstein’s theory of special relativity proposes that time is an illusion that moves relative to an observer. An observer traveling near the speed of light will experience time, with all its aftereffects (boredom, aging, etc.) much more slowly than an observer at rest. That’s why astronaut Scott Kelly aged ever so slightly less over the course of a year in orbit than his twin brother who stayed here on Earth. 

There are other scientific theories about time travel, including some weird physics that arise around wormholesblack holes and string theory. For the most part, though, time travel remains the domain of an ever-growing array of science fiction books, movies, television shows, comics, video games and more. 


Einstein developed his theory of special relativity in 1905. Along with his later expansion, the theory of general relativity, it has become one of the foundational tenets of modern physics. Special relativity describes the relationship between space and time for objects moving at constant speeds in a straight line. 

The short version of the theory is deceptively simple. First, all things are measured in relation to something else — that is to say, there is no “absolute” frame of reference. Second, the speed of light is constant. It stays the same no matter what, and no matter where it’s measured from. And third, nothing can go faster than the speed of light.

From those simple tenets unfolds actual, real-life time travel. An observer traveling at high velocity will experience time at a slower rate than an observer who isn’t speeding through space. 

While we don’t accelerate humans to near-light-speed, we do send them swinging around the planet at 17,500 mph (28,160 km/h) aboard the International Space Station. Astronaut Scott Kelly was born after his twin brother, and fellow astronaut, Mark Kelly. Scott Kelly spent 520 days in orbit, while Mark logged 54 days in space. The difference in the speed at which they experienced time over the course of their lifetimes has actually widened the age gap between the two men.

“So, where[as] I used to be just 6 minutes older, now I am 6 minutes and 5 milliseconds older,” Mark Kelly said in a panel discussion on July 12, 2020, Space.com previously reported. “Now I’ve got that over his head.” 


The difference that low earth orbit makes in an astronaut’s life span may be negligible — better suited for jokes among siblings than actual life extension or visiting the distant future — but the dilation in time between people on Earth and GPS satellites flying through space does make a difference. 

The Global Positioning System, or GPS, helps us know exactly where we are by communicating with a network of a few dozen satellites positioned in a high Earth orbit. The satellites circle the planet from 12,500 miles (20,100 kilometers) away, moving at 8,700 mph (14,000 km/h). 

According to special relativity, the faster an object moves relative to another object, the slower that first object experiences time. For GPS satellites with atomic clocks, this effect cuts 7 microseconds, or 7 millionths of a second, off each day, according to American Physical Society publication Physics Central

Then, according to general relativity, clocks closer to the center of a large gravitational mass like Earth tick more slowly than those farther away. So, because the GPS satellites are much farther from the center of Earth compared to clocks on the surface, Physics Central added, that adds another 45 microseconds onto the GPS satellite clocks each day. Combined with the negative 7 microseconds from the special relativity calculation, the net result is an added 38 microseconds. 

This means that in order to maintain the accuracy needed to pinpoint your car or phone — or, since the system is run by the U.S. Department of Defense, a military drone — engineers must account for an extra 38 microseconds in each satellite’s day. The atomic clocks onboard don’t tick over to the next day until they have run 38 microseconds longer than comparable clocks on Earth.

Given those numbers, it would take more than seven years for the atomic clock in a GPS satellite to unsync itself from an Earth clock by more than a blink of an eye. (We did the math: If you estimate a blink to last at least 100,000 microseconds, as the Harvard Database of Useful Biological Numbers does, it would take thousands of days for those 38 microsecond shifts to add up.) 

This kind of time travel may seem as negligible as the Kelly brothers’ age gap, but given the hyper-accuracy of modern GPS technology, it actually does matter. If it can communicate with the satellites whizzing overhead, your phone can nail down your location in space and time with incredible accuracy. Click here for more Space.com videos…


General relativity might also provide scenarios that could allow travelers to go back in time, according to NASA. But the physical reality of those time-travel methods are no piece of cake. 

Wormholes are theoretical “tunnels” through the fabric of space-time that could connect different moments or locations in reality to others. Also known as Einstein-Rosen bridges or white holes, as opposed to black holes, speculation about wormholes abounds. But despite taking up a lot of space (or space-time) in science fiction, no wormholes of any kind have been identified in real life. 

“The whole thing is very hypothetical at this point,” Stephen Hsu, a professor of theoretical physics at the University of Oregon, told Space.com sister site Live Science. “No one thinks we’re going to find a wormhole anytime soon.”

Besides the absence of identifiable wormholes, another obstacle in the way of wormhole time travel is their hypothetical size. Primordial wormholes are predicted to be infinitesimally small, about 10^-34 inches (10^-33 centimeters) at the “mouth” of the tunnel. As the universe expands, it’s possible that wormholes could stretch along with it, but other problems take hold. 

Even hypothetical wormholes are expected to be extremely unstable, Hsu said, blinking in and out of existence before anything could travel through them. 

“You would need some very exotic type of matter in order to stabilize a wormhole,” Hsu added, “and it’s not clear whether such matter exists in the universe.”


While Einstein’s theories appear to make time travel difficult, some researchers have proposed other solutions that could allow jumps back and forth in time. These alternate theories share one major flaw: As far as scientists can tell, there’s no way a person could survive the kind of gravitational pulling and pushing that each solution requires. 

Infinite cylinder theory

Astronomer Frank Tipler proposed a mechanism (sometimes known as a Tipler Cylinder) where one could take matter that is 10 times the sun’s mass, then roll it into a very long, but very dense cylinder. The Anderson Institute, a time travel research organization, described the cylinder as “a black hole that has passed through a spaghetti factory.”

After spinning this black hole spaghetti a few billion revolutions per minute, a spaceship nearby — following a very precise spiral around the cylinder — could travel backwards in time on a “closed, time-like curve,” according to the Anderson Institute. 

The major problem is that in order for the Tipler Cylinder to become reality, the cylinder would need to be infinitely long or be made of some unknown kind of matter. At least for the foreseeable future, endless interstellar pasta is beyond our reach.

Time donuts

Theoretical physicist Amos Ori at the Technion-Israel Institute of Technology in Haifa, Israel, proposed a model for a time machine made out of curved space-time — a donut-shaped vacuum surrounded by a sphere of normal matter.

“The machine is space-time itself,” Ori told Live Science. “If we were to create an area with a warp like this in space that would enable time lines to close on themselves, it might enable future generations to return to visit our time.”

There are a few caveats to Ori’s time machine. First, visitors to the past wouldn’t be able to travel to times earlier than the invention and construction of the time donut. Second, and more importantly, the invention and construction of this machine would depend on our ability to manipulate gravitational fields at will — a feat that may be theoretically possible, but is certainly beyond our immediate reach.


Time travel has long occupied a significant place in fiction. Since as early as the “Mahabharata,” an ancient Sanskrit epic poem compiled around 400 B.C., humans have dreamed of warping time, Lisa Yaszek, a professor of science fiction studies at the Georgia Institute of Technology in Atlanta, told Live Science

Every work of time-travel fiction creates its own version of space-time, glossing over one or more scientific hurdles and paradoxes to achieve its plot requirements. 

Some make a nod to research and physics, like “Interstellar,” a 2014 film directed by Christopher Nolan. In the movie, a character played by Matthew McConaughey spends a few hours on a planet orbiting a supermassive black hole, but because of time dilation, observers on Earth experience those hours as a matter of decades. 

Others take a more whimsical approach, like the “Doctor Who” television series. The series features the Doctor, an extraterrestrial “Time Lord” who travels in a spaceship resembling a blue British police box. “People assume,” the Doctor explained in the show, “that time is a strict progression from cause to effect, but actually from a non-linear, non-subjective viewpoint, it’s more like a big ball of wibbly-wobbly, timey-wimey stuff.” 

Long-standing franchises like the “Star Trek” movies and television series, as well as comic universes like DC and Marvel Comics revisit the idea of time travel over and over. 

Here is an incomplete (and deeply subjective) list of some influential or notable works of time travel fiction:

Books about time travel:

  • Rip Van Winkle (Cornelius S. Van Winkle, 1819) by Washington Irving
  • A Christmas Carol (Chapman & Hall, 1843) by Charles Dickens
  • The Time Machine (William Heinemann, 1895) by H. G. Wells
  • A Connecticut Yankee in King Arthur’s Court (Charles L. Webster and Co., 1889) by Mark Twain
  • The Restaurant at the End of the Universe (Pan Books, 1980) by Douglas Adams
  • A Tale of Time City (Methuen, 1987) by Diana Wynn Jones
  • The Outlander series (Delacorte Press, 1991-present) by Diana Gabaldon
  • Harry Potter and the Prisoner of Azkaban (Bloomsbury/Scholastic, 1999) by J. K. Rowling
  • Thief of Time (Doubleday, 2001) by Terry Pratchett
  • The Time Traveler’s Wife (MacAdam/Cage, 2003) by Audrey Niffenegger
  • All You Need is Kill (Shueisha, 2004) by Hiroshi Sakurazaka

Movies about time travel:

  • Planet of the Apes (1968)
  • Superman (1978)
  • Time Bandits (1981)
  • The Terminator (1984)
  • Back to the Future series (1985, 1989, 1990)
  • Star Trek IV: The Voyage Home (1986)
  • Bill & Ted’s Excellent Adventure (1989)
  • Groundhog Day (1993)
  • Galaxy Quest (1999)
  • The Butterfly Effect (2004)
  • 13 Going on 30 (2004)
  • The Lake House (2006)
  • Meet the Robinsons (2007)
  • Hot Tub Time Machine (2010)
  • Midnight in Paris (2011)
  • Looper (2012)
  • X-Men: Days of Future Past (2014)
  • Edge of Tomorrow (2014)
  • Interstellar (2014)
  • Doctor Strange (2016)
  • A Wrinkle in Time (2018)
  • The Last Sharknado: It’s About Time (2018)
  • Avengers: Endgame (2019)
  • Tenet (2020)
  • Palm Springs (2020)
  • Zach Snyder’s Justice League (2021)
  • The Tomorrow War (2021)

Television about time travel:

  • Doctor Who (1963-present)
  • The Twilight Zone (1959-1964) (multiple episodes)
  • Star Trek (multiple series, multiple episodes)
  • Samurai Jack (2001-2004)
  • Lost (2004-2010)
  • Phil of the Future (2004-2006)
  • Steins;Gate (2011)
  • Outlander (2014-present)
  • Loki (2021-present)

Games about time travel:

  • Chrono Trigger (1995)
  • TimeSplitters (2000-2005)
  • Kingdom Hearts (2002-2019)
  • Prince of Persia: Sands of Time (2003)
  • God of War II (2007)
  • Ratchet and Clank Future: A Crack In Time (2009)
  • Sly Cooper: Thieves in Time (2013)
  • Dishonored 2 (2016)
  • Titanfall 2 (2016)
  • Outer Wilds (2019)

How did Mars get its two “impossible” moons?

Phobos and Deimos only have two explanations, and neither one adds up.

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  • Phobos and Deimos are the two small moons of Mars, the only rocky planet besides Earth with a moon. 
  • Captured asteroids would not orbit in the same plane, and impact simulations cannot reproduce Phobos and Deimos. 
  • But if an impact also created a large, innermost, third moon, maybe Mars can be explained after all.

As far as we know, there are exactly three ways that a planet can wind up possessing one or more moons.

The first way is from a circumplanetary disk, where the material that accrues around a proto-star not only fragments into planetesimals that grow and evolve but the largest protoplanets acquire their own disks of material around them, which leads to moons. This primarily applies to gas giants and is likely responsible for most of the moons in the Jovian, Saturnian, and Uranian systems.

The second way is through gravitational capture, which explains moons with bizarre orbital orientations and densities that do not match up with the parent planet’s material. This applies to moons like Saturn’s Phoebe or Neptune’s Triton, which likely both originated from the Kuiper belt.

And finally, the third way is through a major collision, which kicks up debris that coalesces into one or more natural satellites: This is the likely origin of not only Earth’s moon but all of the moons of Pluto.

And yet, when we look at all three of these methods, not a single one is capable of explaining the Martian system, with its two small, closely orbiting moons, Phobos and Deimos. On the surface, these Martian moons appear to be impossible on their own. Fortunately, when we put the other puzzle pieces together, one scenario stands out above all the rest.

The relative sizes of the asteroid-like moons of Mars, Phobos and Deimos. Phobos is the innermost moon of Mars, while the smaller Deimos is more than twice as far away. Despite their appearance being similar to asteroids, it is thought that Phobos and Deimos were once joined by a larger, third, inner moon, which has since decayed and fallen back to Mars. All are thought to originate from a giant, ancient impact. (Credit: NASA / JPL-Caltech)

When it comes to planets beyond our own solar system, we have not yet advanced to the point where current technology can unambiguously detect the presence of a moon. Direct imaging has been able to reveal the extended material around a newly forming protoplanet — surefire evidence of a circumplanetary disk that will almost certainly grow into one or more moons — but cannot yet resolve moons around mature exoplanets.

Similarly, the transit method is also limited. Sure, when an exoplanet passes in front of its parent star from our perspective, it blocks a portion of the star’s light, revealing the physical size and orbital period of the planet, once numerous transits build up. If exomoons are present, they can lead to additional flux dips superimposed atop the one caused by the planet and can also lead to transit timing variations as the orbiting moon causes the planet to move forward-and-backward in its orbit by small amounts.

Unfortunately, a non-uniformly reflective planet can exhibit a signal that is observationally indistinguishable from a planet/moon combination with superimposed flux dips. Similarly, the gravitational pull of other masses, like yet-undetected planets, can cause identical transit timing variations as exomoons.

Based on the Kepler lightcurve of the transiting exoplanet Kepler-1625b, we were able to infer the existence of a potential exomoon. The fact that the transits did not occur with the exact same periodicity, but instead displayed timing variations, was the major clue that led researchers in that direction. The exomoon nature is still debated. (Credit: NASA GSFC / SVS / Katrina Jackson)

As a result, we can only look to our own solar system for information about where moons come from. When it comes to Mars, though, none of the three methods quite fit the bill.

Why the Mars moons are “impossible”

The circumplanetary disk option only seems to apply to worlds that are massive enough to have come to dominate their orbits very early on in the history of the solar system. Only by gathering large amounts of mass in one place, early on, can a planet draw enough material into its gravitational well to lead to its own lunar system. Put simply, Mars is too low in mass to have formed with moons around it.

Gravitational capture looks tempting, especially given the superficial similarities between Phobos and Deimos and the other asteroids. However, captured bodies always wind up in randomly oriented orbits: frequently inclined and just as likely to be retrograde (opposite to the planet’s rotation) as prograde (in the same direction as its rotation). Yet Phobos and Deimos not only orbit in the same plane as one another, they orbit within ~1° of Mars’ rotational plane. If these are captured asteroids, it was an almost magical occurrence.

And yet, while that leaves the collisional origin as the third and final option, that does not work well, either. No matter what parameters are inputted into simulations — a fast or slow impactor, a massive or low mass one, a shallow or deep impact angle, etc. — there is no combination of parameters that yields two small, low-mass moons like we actually find around Mars.

Mars, Phobos, and Deimos, to scale, with their orbits to scale as well. No other moons are this close to their parent world for the known planets, but it is possible that asteroids and Kuiper belt objects that have undergone major collisions will have comparable systems. (Credit: Nbound at English Wikipedia)

When we take all of this together, it might be tempting to conclude that Mars is a mystery, and the origin of its lunar system remains obscure to us. But the more we have studied the red planet, the more circumstantial evidence we have begun to gather that simply looking at the moons that Mars possesses does not tell us the full story. In fact, the same can be said of the most familiar moon in our solar system: our own.

The origin of Earth’s moon

On Earth, for example, we did not know where the moon came from for an extremely long time. As recently as the 1980s, scientists considered that the moon might be a gravitationally captured object, despite the fact that it orbits prograde, out of the plane of Earth’s orbit around the sun by only 5°, and is tidally locked to the Earth.

However, in order to gravitationally capture a large, massive object, it has to be capable of shedding both momentum and angular momentum, requiring that something else get ejected. Unless Earth had either a rich lunar system of its own at birth — as we assume Neptune once did, leading to the capture of Triton at the expense of all its pre-existing exterior moons — or an enormous atmosphere capable of causing a tremendous amount of aerobraking, the capture scenario would be an impossibility.

This analysis of a fragment of a lunar rock recovered from the Apollo 14 mission shows a zircon inclusion, which may have formed on Earth during or even prior to the impact that gave rise to the moon. (Credit: J.J. Bellucci et al., Earth and Planetary Sci. Lett., 2019)

Many hypotheses about the origin of Earth’s moon have been floated throughout history, but modern analyses of the material brought back from the moon during the Apollo missions have largely settled the story. The Earth and moon, as determined by analyzing the elements and isotopes that their surface rocks are made from, have identical oxygen isotope ratios, something that is different between our planet and every other planet.

Not only does this point to a common origin for the rocks found here and on the moon, but two other pieces of evidence show that the moon is almost as old as, but not quite as old as, the oldest objects in the solar system. While the most ancient asteroids have been dated to be 4.56 billion years old, we have two independent methods of estimating the age of the moon.

  1. Lunar samples brought back from the Apollo 14 mission contained zircon fragments, which allow for an incredibly accurate form of radiometric dating to be performed: uranium-lead dating, which yields an age for the moon of 4.51 billion years.
  2. By combining data about the thermal conductivity of the moon’s crust with the cooling properties of a hypothetical lunar magma ocean and folding in the ages and compositions of moon rocks, an age estimate of 4.43 billion years was obtained.

The Moon formed early on in the history of the solar system, but well after the completion of planetary formation. A major collision is the only explanation that fits on all counts.

An illustration of what a synestia might look like: a puffed-up ring that surrounds a planet subsequent to a high-energy, large angular momentum impact. This likely represents the aftermath of the collision that resulted in the formation of our moon. (Credit: Sarah Stewart / UC Davis / NASA)

An explanation for Mars’ “impossible” moons

Given that so many pieces of evidence needed to be combined to reveal the origin of our own moon, it makes sense to gather any and all potentially relevant information about Mars and its moons. Sure, our simulations pretty definitively show that no combination of collisional parameters would have produced two small moons around Mars and nothing else, but that does not rule out an impact scenario for the origin of Phobos and Deimos.

Observational sciences, like astronomy, are fundamentally different from laboratory sciences where you can perform and control your experiments however you like. In an observational science, all you get is a snapshot of what the system you are examining is like over the very brief interval you get to observe it.

For our solar system, which has been around for over 4.5 billion years, we have only a few thousand years of documented astronomical history, at most. The moons of Mars were only discovered in the late 19th century, less than 150 years ago. To claim that Mars has two moons is certainly correct, today, but we have to keep the cardinal rule of all observational sciences in mind whenever we draw conclusions. When we look at what we have, today, all we are seeing are the survivors. It is eminently possible that what exists today is just a subset of what once existed long ago.

Winds at speeds up to 100 km/hr travel across the Martian surface. The craters in this image, caused by impacts in Mars’ past, all show different degrees of erosion. Some still have defined outer rims and clear features within them, while others are much smoother and featureless, almost seeming to run into one another or merge with their surroundings. (Credit: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO)

When we look at Mars, it is easy to notice its surface features, which are numerous and varied and tell a dramatic story. Mars has a reddish color to it, evidence of widespread ferric oxide: the result of reactions taking place between iron and oxygen. The atmosphere of Mars is rich in both water vapor and carbon dioxide, both of which can oxidize iron and also combine to point toward a wet, watery history on the red planet. Its presently thin, tenuous atmosphere with what appear to be dried-up riverbeds on its surface and hematite spheres in lowland regions further indicate a watery past, with a much thicker atmosphere that must have persisted for a billion years or more.

But another spectacular feature of Mars is its heavily cratered outer layer, with dramatic highlands and lowlands. Although there are a number of prominent features like mountains, volcanoes, basins, and multiple layers of craters, perhaps the most dramatic difference can be seen between the northern and southern hemispheres of the red planet. While there are topographical variations across both hemispheres, there is an enormous basin covering half of the planet, where for some reason, roughly 50 percent of Mars is around five kilometers (three miles) lower in elevation than the rest of the planet.

The Mars Orbiter Laser Altimeter (MOLA) instrument, part of the Mars Global Surveyor, collected over 200 million laser altimeter measurements in constructing this topographic map of Mars. The Tharsis region, at center-left, is the highest elevation region on the planet, while the lowlands appear in blue. Note the much lower elevation of the northern hemisphere compared to the southern, with a mean difference in elevation of around 5 km. (Credit: Mars Global Surveyor MOLA Team)

How could this be possible? Even on a geologically active world like Earth, such a configuration probably never existed. Even back when the continents were all interconnected, forming Pangaea, there were likely large ridges, subduction zones, and other tremendous variations in elevation along the ocean floor, preventing the uniform, deep basin that has persisted on Mars for at least the past 3 billion years or so.

It is generally quite difficult to make a planet lopsided like this, particularly if its structure is driven by gradual, internal processes. However, there is an easy way to make a large, deep, sustaining basin: from a large impact. Not, mind you, the type of impact that created our own moon, which required a Mars-sized body striking a world nearly as large as Earth already is today. Instead, a slower collision between perhaps a Pallas-sized body (Pallas being the 3rd largest asteroid in our asteroid belt, well behind Ceres but nearly as massive as Vesta) and early Mars could have left a dramatic scar of precisely this type.

Rather than the two moons we see today, a collision followed by a circumplanetary disk may have given rise to three moons of Mars, where only two survive today. This hypothetical transient moon of Mars, proposed in a 2016 paper, is now the leading idea in the formation of Mars’ moons. (Credit: LabEx UnivEarthS / Université de Paris Diderot)

I am not attempting to suggest that a slow, massive collision kicked up debris that then created Phobos and Deimos; that is not consistent with any realistic scenario. Instead, however, it is plausible that:

  1. an early major collision gave rise to a large debris cloud,
  2. that cloud coalesced into not two but three moons,
  3. where the innermost moon was largest, followed by Phobos and then Deimos,
  4. and then the innermost moon eventually fell back onto Mars, perhaps after being tidally destroyed, creating the depressed basin we see today.

This provides a possible mechanism for explaining what remains around Mars today, while still being consistent with what is obtainable within realistic physical scenarios. When we run our simulations for the types of lunar systems that could have arisen from a giant impact on a Mars-like body back in the early stages of our solar system, a large, few-hundred-kilometer inner moon could have existed alongside Phobos and Deimos, having fallen back to Mars in an era in which only single-celled life existed on Earth. It is the one scenario that has no major conflicts with the full suite of available evidence.

Artist’s concept of Japan’s Mars Moons eXploration (MMX) spacecraft, carrying a NASA instrument to study the Martian moons Phobos and Deimos. The mission should contain a sample return component and, after collecting material from Phobos in 2024, should return that component to Earth in July of 2029. We could know if Mars possessed ancient life, and if Phobos is made out of Martian material, before the current decade is over. (Credit: NASA)

Of course, there is only one way to be certain that Phobos and Deimos are made from the same materials as Mars, rather than being captured asteroids: to land on one of them and return that material to Earth. That is precisely what Japan’s Mars Moons eXploration (MMX) spacecraft is designed to do. The plan is to land on Phobos in 2024, collect material, and return it to Earth before the end of the decade, similar to what previous sample return missions have done on asteroids Itokawa and Ryugu. If Phobos is made of the same material that Mars is composed of, this will be the surefire way to find out.

For more than a century — for practically the entire duration that we have known Mars possesses moons — we have wondered about the origin of these Martian bodies. Yet the fact that we have only been around for an astronomical instant makes reconstructing the history of the solar system that much more difficult. Considering that in another few billion years, Phobos will likely fall back to Mars as well, leaving only Deimos behind, perhaps we should adopt a more positive perspective. After all, at least we have enough remaining clues today to reconstruct the cosmic story that tells us how our solar system grew up. The more time that goes by, the greater the odds that our early history gets overwritten in a way that completely erases the critical evidence we need to know the answer to perhaps the greatest question of all: where did all this come from?

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Potentially Hazardous Asteroid Going 21,000 MPH Is On Close Approach With Earth

Asteroid 2021 NY1 measures up to 1000 feet in diameter, making it a very large asteroid. It will enter the Earth’s orbit, heading towards us at a speed of nearly 21,000 mph.

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Asteroid 2021 NY1 Going 21000 MPH Is On Close Approach With Earth

  • 2021 NY1, a very large asteroid, up to 984 feet wide, will be closely flying by Earth in September.
  • Classified as a Potentially Hazardous Near-Earth Object (NEO) by NASA, Asteroid 2021 NY1 will be traveling at a speed of around 20,893 miles per hour.

Mark your calendars. Asteroid 2021 NY1 is about to come by and say hello to Earth.

The Apollo-class asteroid, which is somewhere between 427 and 984 feet wide, is predicted by NASA to be on close approach and will pass by our planet on Sept. 22, 2021.

It will come within 930,487 miles (1,498,113 kilometers) of Earth at a speed of almost 21,000 miles per hour.

While that may not sound very close, in relative terms of outer space it isn’t completely insignificant.

For instance, the moon is 238,855 miles from Earth, while the planet Mars is 245.22 million miles away. So 930,487 miles is pretty close.

That’s assuming that the Yarkovsky Effect, which can change an asteroid’s orbital path, doesn’t occur with this particular space rock.

Asteroid 2021 NY1 Going 21000 MPH Is On Close Approach With Earth


This is why NASA classifies Asteroid 2021 NY1 as a Near-Earth Object, which they define as “an asteroid or comet that approaches our planet less than 1.3 times the distance from Earth to the Sun (the Earth-Sun distance is about 93 million miles).”

Asteroid 2021 NY1 is also considered to be a Potentially Hazardous Object by NASA, “because the gravitational tug of the planets could, over time, cause an object’s orbital path to evolve into an Earth-crossing orbit. This allows for the possibility of a future collision.”

According to SpaceReference.org, “2021 NY1 orbits the sun every 1,400 days (3.83 years), coming as close as 0.99 AU and reaching as far as 3.90 AU from the sun.”

So it’s all good, right? Sure. If you believe NASA, who never tries to conceal the truth and never keeps anything hidden from the American public.

This asteroid is one of the most likely to hit Earth. NASA Explains.

This asteroid is one of the most likely to hit Earth. Here’s what it means for our future.

New ultraprecise measurements show that the asteroid Bennu has a higher chance than thought of impacting our planet sometime in the next 300 years, NASA says.

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For hundreds of millions of years, a top-shaped rubble pile called Bennu has orbited the sun in relative isolation. The asteroid, about a third of a mile wide at its equator, poses no immediate threat to our planet. But hundreds of years from now, there is a small chance that Bennu could slam into Earth.

In a new study published in the scientific journal Icarus, scientists used data from NASA’s OSIRIS-REx spacecraft to make a precise calculation of Bennu’s orbit and its future proximity to our home planet. The researchers then analyzed the impact hazard between now and the year 2300. The study finds a 1-in-1,750 chance of a future collision over the next three centuries—a slightly higher probability than previously estimated.

Nearly all of the riskiest encounters with Bennu will occur in the late 2100s and early 2200s, with the single likeliest impact coming on the afternoon of September 24, 2182. On that Tuesday, Bennu has about a 1-in-2,700 chance of hitting Earth.

The team—led by Davide Farnocchia, a navigation engineer at NASA’s Jet Propulsion Laboratory—reached its revised estimate by pinpointing Bennu’s distance from Earth to within about seven feet at dozens of times between 2019 and 2020. That level of precision is like measuring the distance between the Empire State Building and the Eiffel Tower to within a few thousandths of an inch.

“Bennu is by far the best characterized asteroid in the solar system,” says University of Arizona planetary scientist Dante Lauretta, OSIRIS-REx’s principal investigator and the study’s senior author. “We know where it’s going to be over 100 years into the future, within meters. No other object in the solar system has that level of fidelity to its orbital solution—even Earth!”

University of Arizona planetary scientist Amy Mainzer, an expert on near-Earth asteroids who wasn’t involved with the study, lauded the team’s “absolutely white-glove” calculations. “If you want to be able to predict where [an asteroid] is going to go in the future, that prediction is entirely determined by how well you can measure where it is today,” she says. “This team has made an extremely precise measurement.”

Despite the slightly higher chance of impact, the risks from Bennu shouldn’t keep anyone awake at night. There’s more than a 99.9 percent chance that Bennu will not hit Earth in the next three centuries, and an impact from Bennu wouldn’t cause a mass extinction like the dino-killing Chicxulub impact 66 million years ago. That asteroid was probably about six miles across; Bennu is less than a third of a mile wide, on average.

Even so, a collision with Bennu would be regionally devastating. An impact would pack the energy of more than 1.1 billion tons of TNT, roughly two million times the energy of last year’s devastating port explosion in Beirut, Lebanon.

Ever since Bennu’s discovery in September 1999, astronomers have carefully tracked the asteroid’s orbit with ground-based telescopes, including Puerto Rico’s iconic but now lost Arecibo Observatory. These data have let astronomers predict Bennu’s future location reasonably well over the next century.

Bennu is classified as a “potentially hazardous asteroid,” meaning the object is more than 460 feet (140 meters) wide and could theoretically come within 4.65 million miles of Earth. A 2014 study found that the asteroid had roughly a 0.037 percent chance of colliding with Earth between 2175 and 2199.

But until now, simulations have run into issues beyond September 2135. Previous predictions had found that Bennu will pass within 75,000 to 330,000 miles of Earth in 2135, possibly taking the asteroid closer to Earth than the moon. Bennu has practically no chance of hitting Earth then, but depending on precisely when and where Bennu makes its close approach, our planet’s gravity could tweak the asteroid’s orbit enough to put it on a future collision course.

Computer simulations have identified the small regions of space that Bennu would have to pass through to set up a future impact. The key question is whether Bennu’s actual trajectory in 2135 will pass through any of these “keyholes,” which range from several hundred feet to a few miles wide. Answering that question requires scientists to chart Bennu’s current trajectory—and everything that could affect its future path—with unprecedented precision.

OSIRIS-REx arrived at Bennu in late 2018 as NASA’s first—and humankind’s third—attempt to sample the surface of an asteroid. The spacecraft, which snatched a dusty, pebbly sample in October 2020, is currently on its way back to Earth to drop off the precious material. But before it grabbed its sample, OSIRIS-REx spent nearly two years orbiting and studying rubble-strewn Bennu.

Because the spacecraft spent so long tagging along with the asteroid, Farnocchia and his colleagues were able to use data from OSIRIS-REx to precisely chart the asteroid’s location. Their approach had the flavor of a high-school trigonometry problem: If you know the distance from OSIRIS-REx to Bennu, and the distance from OSIRIS-REx to Earth, then you can figure out the distance between Earth and Bennu.

The team focused on periods when researchers knew OSIRIS-REx’s position relative to Bennu to within a meter (3.3 feet), based on images the spacecraft was taking of the asteroid’s surface. They then measured the timing of radio signals exchanged between OSIRIS-REx and Earth to within 15 billionths of a second.

Combining these data meant that Farnocchia’s team could calculate the distance between Earth and Bennu to within several feet, at distances ranging from 52 million to more than 201 million miles.

The team also used OSIRIS-REx data to constrain a key non-gravitational force acting on Bennu that’s known as the Yarkovsky effect. As sunlight heats up Bennu’s surface, the asteroid’s surface re-emits energy as it cools. Because Bennu rotates, the net result is a subtle thrust acting on the asteroid.

Farnocchia’s team is now able to provide a precise estimate of how the Yarkovsky effect tweaks Bennu’s orbit over time. In a NASA press briefing on August 11, Farnocchia noted that this force is equal to the weight of three grapes on Earth—and that’s enough to cause Bennu to drift by about 934 feet a year.

A swirling solar system

The new study finds that in 2135, Bennu will come within about 123,000 miles of Earth’s surface, give or take 6,000 miles, a much more precise range than previous estimates. Even though this finding rules out many previously identified keyholes, some keyholes—and future collision courses—still fall within the orbit’s margin of error. From there, the team was able to revise their estimates for Bennu’s collision risk.

The lingering uncertainty over the space rock’s future trajectory doesn’t stem from the asteroid itself, or even from OSIRIS-REx’s data. It comes from the rest of the solar system.

When Farnocchia and his colleagues ran their simulations, they had to account for many factors, including how sunlight heats up Bennu and how hundreds of other objects in the solar system, even as far away as Pluto, gravitationally tug at the asteroid. The trouble is, researchers had to estimate the masses for most of the objects within a key group: the 343 largest bodies in the asteroid belt.

“It’s amazing to me that other asteroids have any influence at all,” says Lauretta. Once other sources of error get small enough, “these effects show up, and you’re like, Wow.”

Future missions should help refine those estimates. NASA’s upcoming Near-Earth Object (NEO) Surveyor mission, scheduled to launch in 2026, is an infrared space telescope designed to look for asteroids’ heat signatures, which can be used to estimate their sizes. The telescope is expected to discover hundreds of thousands more asteroids, as well as provide better data on the asteroids that have already been found.

“You want to know as much as you can about as many of the objects out there [as you can], so that you have a reasonable idea of what’s likely to happen,” says Mainzer, the NEO Surveyor’s principal investigator.

Mainzer and Lauretta add that sending more spacecraft to more asteroids would help—and OSIRIS-REx itself is poised to get in on the action. In September 2023, the spacecraft will fly by Earth, drop a capsule full of Bennu samples into the Utah desert, and continue its journey through the solar system. So far, Lauretta’s team has found only one viable follow-on target for OSIRIS-REx: the near-Earth asteroid Apophis, which will make a close approach to Earth in April 2029.

Earth is safe from Apophis for at least the next century. But setting aside its risks to our planet, visiting worlds like Apophis will give scientists whole new vistas and terrains to explore—and a broader sense of the solar system’s history.
Humankind also has more than a century to continue monitoring Bennu’s risk to Earth—and to modify that risk, if necessary. Already, space agencies are testing the procedures and technologies needed to neutralize an asteroid’s threat. In 2022, NASA’s DART spacecraft will slam into a roughly 560-foot-wide moonlet orbiting a near-Earth asteroid, with the goal of altering the moonlet’s orbit.

If humankind is threatened by an asteroid impact in the future, bigger versions of these “kinetic impactors” could be used to nudge the asteroid into a safe orbit—so long as we have at least several years’ notice before a predicted collision. For objects like Bennu, which was discovered nearly 200 years before any potential impacts, Mainzer says that humankind has “lots and lots and lots of options.”

Space station detectors found the source of weird ‘blue jet’ lightning

A ‘blue bang’ sparks an unusual type of lightning in the upper atmosphere

blue jet illustration
The International Space Station spotted an exotic type of upside-down lightning called a blue jet (illustrated) zipping up from a thundercloud into the stratosphere in 2019.DTU SPACE, DANIEL SCHMELLING/MOUNT VISUAL

Scientists have finally gotten a clear view of the spark that sets off an exotic type of lightning called a blue jet.

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Blue jets zip upward from thunderclouds into the stratosphere, reaching altitudes up to about 50 kilometers in less than a second. Whereas ordinary lightning excites a medley of gases in the lower atmosphere to glow white, blue jets excite mostly stratospheric nitrogen to create their signature blue hue.

Blue jets have been observed from the ground and aircraft for years, but it’s hard to tell how they form without getting high above the clouds. Now, instruments on the International Space Station have spotted a blue jet emerge from an extremely brief, bright burst of electricity near the top of a thundercloud, researchers report online January 20 in Nature.

Understanding blue jets and other upper-atmosphere phenomena related to thunderstorms, such as sprites (SN: 6/14/02) and elves (SN: 12/23/95), is important because these events can affect how radio waves travel through the air — potentially impacting communication technologies, says Penn State space physicist Victor Pasko, who was not involved in the work.

Cameras and light-sensing instruments called photometers on the space station observed the blue jet in a storm over the Pacific Ocean, near the island of Nauru, in February 2019. “The whole thing starts with what I think of as a blue bang,” says Torsten Neubert, an atmospheric physicist at the Technical University of Denmark in Kongens Lyngby. That “blue bang” was a 10-microsecond flash of bright blue light near the top of the cloud, about 16 kilometers high. From that flashpoint, a blue jet shot up into the stratosphere, climbing as high as about 52 kilometers over several hundred milliseconds.

The spark that generated the blue jet may have been a special kind of short-range electric discharge inside the thundercloud, Neubert says. Normal lightning bolts are formed by discharges between oppositely charged regions of a cloud — or a cloud and the ground — many kilometers apart. But turbulent mixing high in a cloud may bring oppositely charged regions within about a kilometer of each other, creating very short but powerful bursts of electric current, Neubert says. Researchers have seen evidence of such high-energy, short-range discharges in pulses of radio waves from thunderstorms detected by ground-based antennas.

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O UFOs, Where Art Thou?

Five reasons why sorting all of this out is so scientifically challenging

O UFOs, Where Art Thou?
Credit: Artem Peteriatko Getty Images
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Just before the release in June of the much-anticipated Pentagon report on unidentified aerial phenomena (UAP), I sat down to try to create a list of the greatest hurdles to UAPs’ scientific analysis. What I came up with were five major challenges that are described here, together with a cross-comparison with some of the statements made in the published government report. Although only nine pages long, that report turns out to be thorough, careful and scientifically accurate in that it fully expresses how little certainty can be drawn from the data to hand. As the saying goes: the more things change, the more they stay the same.

Challenge No. 1: All UAP/UFO incidents are nonrepeatable: we can’t go back and perform the “experiment” of that exact observation again.

For science in general, this kind of thing is a big headache. A lack of repeatability or replication poses a very significant challenge for the interpretation of data (especially if those data are noisy and incomplete); for filling in obvious gaps; and for eliminating or supporting any hypotheses. As the Pentagon report states: “Limited data leaves most UAP unexplained….” Limited, anecdotal and nonrepeatable are hardly the words you want to use, but they apply here.

Challenge No. 2: There is nothing systematic in how incidents are recorded or reported. Different camera systems, radar systems, data processing, observers and environmental circumstances mean that each incident is, in effect, an uncontrolled experiment, with few ways to ascertain the real quality and sensitivity of data.

Again, the Pentagon report states effectively the same point: “The limited amount of high-quality reporting on unidentified aerial phenomena (UAP) hampers our ability to draw firm conclusions about the nature or intent of UAP.” The report then goes on to suggest a potentially useful task of: “Consistent consolidation of reports from across the federal government, standardized reporting, increased collection and analysis, and a streamlined process for screening.”

This is really important; the report is very, very specific about the lack of appropriateness of typical military sensor equipment for this sort of analysis. “The sensors mounted on U.S. military platforms are typically designed to fulfill specific missions. As a result, those sensors are not generally suited for identifying UAP.”

Challenge No. 3: There is no easy way to account for “cherry-picking” of data. We don’t know how often pilots or other observers see something unexpected but then, a minute later, figure out what they’re witnessing (or at least convince themselves they’ve done so) and consequently don’t report anything. There could be thousands of such incidents, or very few. We don’t know, and those “mundane” cases could actually represent all cases.

The report does discuss the “stigma” surrounding personnel or observers reporting UAPs, but it also states that out of the 144 reports that were studied, only 18 incidents (covered in 21 of the reports) appeared to demonstrate “advanced technology,” inasmuch as there was an appearance of unusual aeronautical behavior in movement.ADVERTISEMENT

In a small (unspecified) number of cases there was even evidence of military aircraft systems “processing radio frequency (RF) energy”—whatever that really means; presumably there was some increased radio noise. But, as for all the times that nothing was reported, either because something was quickly identified, or a pilot just chose not to, that remains a total unknown.

Challenge No. 4: If any incidents or observations are genuinely associated with something tangible and physical, we don’t know whether we’re looking at a single underlying phenomenon or many. It’s a bit like going into a zoo blindfolded and trying to understand what you’re hearing and smelling. If there’s only one species you might figure it out, but if there are 100 species, then decoding your experience is going to be very difficult.

Again, the report hits this nail right on the head, with an entire section titled “UAP probably lack a single explanation.” Some of the possibilities offered are: “Airborne clutter … birds, balloons, recreational unmanned aerial vehicles … debris like plastic bags … that muddle a scene,” as well as natural atmospheric phenomena (ice crystals, thermal fluctuations that can register on infrared and radar systems), classified aircraft and the like, and foreign “adversary systems.”

The Pentagon report also provides an outline of ongoing efforts, and possible future directions, for trying to improve all analyses. This includes a more systematic collection of military aircraft sensor data, along with FAA data, and applying machine learning to sift through current and historical information to look for “clusters,” patterns and associations with known phenomena like weather balloons, wildlife movements and other Earth-monitoring databases.

Challenge No. 5: The popular association of UAP with hypotheses involving alien technology creates a severe analysis bias. Usually, science tries to move stepwise towards finding support for a given hypothesis or for eliminating hypotheses, and weighs those options as evenly as possible. But in this case a hypothesis that would require extraordinarily robust evidence in order to be supported (as with Carl Sagan’s famous dictum “Extraordinary claims require extraordinary evidence”), regardless of what some people say, hangs heavily over any analysis or discussion, and there is a vocal community who feel that the answer is already known. That’s a problem.

In fact, and rather ironically, the “sociocultural stigmas” around recording surprising observations mentioned in the report are undoubtedly exacerbated by elements of the UFO community that express ideas or beliefs that are, well, fantastical in nature.

Consequently, observers such as highly trained, professional pilots are likely going to be reticent to mention things they are very surprised by. This relates to point No. 3 and creates bias because the unreported incidents, if further analyzed, could provide significant insight—especially as to how often human observers are simply confused, as opposed to witnessing genuinely unusual phenomena.

Where does all of this leave us? Well, the Pentagon report does suggest ways to improve data collection and analysis, as I’ve described. It also points out that if some UAP do represent physical hazards, or security challenges, it would be important to figure that out. In that sense, there is some possible risk mitigation to be had by investigating UAP further, irrespective of an eventually mundane or extraordinary explanation.

As a scientist who studies the possibilities of life elsewhere in the cosmos, I find myself saying “Well, it seems worth having some more work done on this.” But that’s not because I think it’s likely that extraterrestrials or their probes could be dropping into Earth’s atmosphere. Although as a rational thinker I can’t, and shouldn’t, permanently exclude such possibilities, my point No. 5 bothers me enough that I’d rather follow the stepwise approach. There are other benefits to that strategy too.

In particular, I think that the idea of a vastly more systematic collection of data (from things like state-of-the-art camera systems placed on aircraft or in monitoring locations) would be an interesting activity regardless of what is actually taking place in our skies.

New kinds of high-resolution time-lapse data and high-fidelity monitoring of our planetary environment could have many additional benefits as we try to navigate our way through a perilously changing world. From atmospherics to animal migration to human-generated garbage floating in the air and on the sea, seeing what’s actually going on is always going to help.

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If aliens call, what should we do? Scientists want your opinion.

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The Search for Extraterrestrial Intelligence (SETI) has been growing in confidence and repute lately thanks to astronomer’s detections of habitable worlds and the private funding been poured into the enterprise. With renewed efforts afoot, it’s worth pausing for a moment and asking – well what do we do if we succeed? How should the scientists communicate their results? How will the public react? Social media in particular disrupts the conventional pattern of scientific announcements and poses some interesting challenges for SETI. In this video we perhaps end up asking more questions than answers, but let’s get into a discussion in the comments about how best to proceed!

In the age of fake news, researchers worry conspiracy theories would abound before we could figure out how — or if — to reply to an alien message.

The Very Large Array radio telescope facility in New Mexico
Astronomers use radio telescopes, like the Very Large Array in New Mexico, to listen to the cosmos. They can also use radio telescopes to broadcast messages into space.

The answer to this question could affect all of our lives more than nearly any other policy decision out there: How, if it all, should humanity respond if we get a message from an alien civilization?

And yet politicians and scientists have never bothered to get our input on it.

At long last, that’s changing. A group of researchers in the UK this week released the first major survey on the question. The responses could help inform an international protocol for responding to first contact.

This is a big deal because, as Stephen Hawking and Elon Musk have warned, communicating with extraterrestrials could pose a catastrophic risk to humanity. In fact, if we send out a message and it’s received by less-than-friendly aliens, that could pose an existential threat not only to the human species but to every species on Earth.

Despite the high stakes, scientists have already sent out signals intended to be picked up by aliens. The first one went out in 1974, when the Arecibo radio telescope in Puerto Rico transmitted a broadcast containing information on everything from the position of Earth in our solar system to the double helix structure of DNA.

The Arecibo Observatory is currently running a contest that invites kids to design our next message to E.T. And later this year, an organization called Messaging Extraterrestrial Intelligence (METI) plans to transmit a new message containing information on the periodic table. There’s no law saying they can’t, or even that they need to get some international buy-in.

But the scientists at the UK SETI Research Network (UKSRN) think we’re woefully unprepared to handle an alien message if we receive one. And they say no one class of people should unilaterally decide humanity’s response. As astronomer Martin Dominik put it, “We want to hear people’s views. The consequences affect more people than just scientists.”

So UKSRN has launched a survey online and at the Royal Society’s summer science exhibition in London, which runs July 1-7. Here are three of the questions they’re asking the public:

1) Some people think we should send messages into space even if we don’t receive a message first. What is your opinion?

2) If we receive a message, do you think we should reply/make contact or not? Why?

3) What would you consider a credible source?

That third question reflects a worry I’ve been hearing from astronomers over the past couple of years: If a newly discovered message from aliens is announced, members of the public may use social media to spread all sorts of fake news and conspiracy theories about the aliens, their message, and what it will mean for humanity to communicate with them. In the weeks or months or years it could take scientists to decode the interstellar missive, fear-mongering could tank our chances of responding wisely — or at all.

An alien message “will take time to understand and if that work starts to drag out and there is nothing new we can say, the information vacuum will be filled with speculation,” John Elliott, a UKSRN co-founder, told the Guardian. “Conjecture and rumor will take over.”

In hopes of figuring out how to minimize the problem, the survey asks which information sources you’d trust: Main news channels? Direct quotes from scientists? Official government statements? Other sources?

It also asks if you’d post on social media about the discovery of an alien message. If so, would you restrict yourself to defending the scientific evidence? Or would you maybe engage in speculation? Would the absence of any news on the signal’s decoding encourage you to speculate?

You can see how it’d be useful to scientists to be able to predict the public’s response in these scenarios. But there’s a difference between how I say I’d react when I’m filling out a questionnaire, and how I’d actually react in real life. In addition to that limitation, the UKSRN survey is weakened by the fact that the same person can take it more than once from different devices.

Still, it’s an improvement over the lack of public consultation we’ve seen on these questions in the past.

Who gets to make rules about what happens in space?

For decades, the international community has been exploring the possibility of establishing a mechanism for global oversight when it comes to our engagement with outer space. But even if everyone were to agree that’s a good idea, the question of how to set it up and make it enforceable is incredibly complicated.

The 1967 Outer Space Treaty was an early effort in this vein. Ratified by dozens of countries and adopted by the United Nations against the backdrop of the Cold War, it laid out a framework for international space law. Among other things, it stipulated that the moon and other celestial bodies can only be used for peaceful purposes, and that states can’t store their nuclear weapons in space. The treaty suited its historical context, but it didn’t tackle the concerns people have nowadays about messaging an alien intelligence.

Carl Sagan helped design this early pictorial message to aliens. It was engraved on an aluminum plaque that was attached to the Pioneer 10 spacecraft before its launch in 1972.
Carl Sagan helped design this early pictorial message to aliens. It was engraved on an aluminum plaque that was attached to the Pioneer 10 spacecraft before its launch in 1972.

Another inflection point came in the late 1980s, when scientists with the organization Search for Extraterrestrial Intelligence (SETI) drafted a post-detection protocol, a list of best practices for what to do if and when we ever find aliens. One of its principles reads: “No response to a signal or other evidence of extraterrestrial intelligence should be sent until appropriate international consultations have taken place.”

This protocol was put on file as a brief with the Outer Space Treaty at the UN, and it was endorsed by the International Academy of Astronautics and the International Institute for Space Law. But it has no regulatory force when it comes to those who actively send out messages à la METI.

In 2015, SETI researchers, Musk, and others released a statement criticizing METI efforts. “We feel the decision whether or not to transmit must be based upon a worldwide consensus, and not a decision based upon the wishes of a few individuals with access to powerful communications equipment,” it said. “We strongly encourage vigorous international debate by a broadly representative body prior to engaging further in this activity.”

So far, though, there is still no “broadly representative body” regulating what messages can be sent into space or by whom.

Alessandra Abe Pacini, a researcher at Arecibo who helped generate the idea for the kids’ contest, told me the question of whether any message should be transmitted at all is “very controversial,” adding: “Even here among the scientists at Arecibo, there is no consensus.”

If some of the smartest astronomers in the world can’t come to an in-house agreement, is there any hope that the international community will ever agree? Maybe not, but the UKSRN survey may at least help us find out how much consensus there is or isn’t among the public. That’s a good first step.

Inspiration4, the first all-civilian spaceflight, is now in orbit

The SpaceX mission seeks to raise some $200 million dollars for St. Jude Children’s Research Hospital. 


Inspiration4 / John Kraus

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Last night at 8:02 PM EDT, the crew of Inspiration 4 — the first all-civilian spaceflight — blasted off from historic Launch Complex 39A at NASA’s Kennedy Space Center. Tucked inside a SpaceX Crew Dragon capsule, which was lofted to orbit atop a SpaceX Falcon 9 rocket, are four fortunate astronauts: Sian Proctor, Hayley Arceneaux, Christopher Sembroski, and Jared Isaacman. The latter footed the bill for the trip.

Unlike the recent suborbital spaceflights of billionaires carried out this summer by Blue Origin and Virgin Galactic, Inspiration4 is setting its sights higher, taking the untrained civilian crew all the way to orbit. There, they will circle the Earth for three days, conducting experiments and enjoying their views before returning for a soft water landing off the coast of Florida.

Although Inspiration4 is currently orbiting more than 100 miles above the International Space Station (ISS), one of the mission’s main goals is much more Earth-bound: to raise awareness and funding for St. Jude Children’s Research Hospital. At St. Jude, children receive treatment for cancer and other life-threatening diseases. And perhaps most importantly, families treated at the hospital never receive a bill. The mission hopes to raise $200 million for St. Jude.

The crew

Commanding the Inspiration4 mission is Isaacman, founder and Chief Executive Officer of Shift4 Payments. The American billionaire is also a pilot. Proctor earned her seat by winning a contest hosted by Shift4.

Similarly, Sembroski got his seat from a contest, but not one that he won. Instead, his friend won the seat in a charity raffle for St. Jude and, for personal reasons, declined the seat, instead offering it to Sembroski.


Inspiration4 crew before liftoff. Inspiration4 / John Kraus

Arceneaux was a childhood cancer survivor and former patient at St. Jude who now works at the hospital as a physician’s assistant. She will become the youngest American (and the first person with a prosthetic body part) to venture to space. Arceneaux was personally selected by Isaacman to be on the flight.

Also on board are numerous items that will later be auctioned off for St. Jude, including the first minted non-fungible token (NFT) to be played in orbit. Other items include mission jackets decorated with artwork from St. Jude patients, 66 pounds of hops from Samuel Adams that can be used to create out-of-this-world beer, a to-be-autographed copy of Time with the crew on the cover, and much more.about:blankabout:blank


Inspiration4 / John Kraus

Breaking records left and right

The launch last night went off without a hitch, and it was celebrated with fist bumps by the crew, even as they were still climbing to their final orbital altitude. 

Their excitement, however, is warranted. Besides becoming the first all-civilian mission, Inspiration4 will also be the first orbital human space mission to not dock at the ISS since the final Hubble mission in 2009.

At an orbit of 363 miles (585 kilometers), Inspiration4 is now above both the ISS and the Hubble Space Telescope. In fact, the Inspiration4 crew is currently farther from Earth than any humans have been since the Apollo missions.

One more record Inspiration4 launch helped break: the greatest number of people in space at one time. NASA’s Expedition 65 mission currently has a crew of seven people aboard the ISS, while China’s Shenzhou-12 mission includes three astronauts who are concluding a 90-day trip with their return to Earth tomorrow. So for a few brief days, the four civilians of the Inspiration4 crew brings the total space population up to 14, just edging out the previous record of 13 set in 2009.

Jupiter’s volcanic moon Io is emitting strange radio waves and NASA’s Juno probe is listening

The Juno spacecraft has gotten a private radio show from Jupiter’s closest moon, the highly volcanic Io.

NASA’s Juno spacecraft is “listening” in on radio emissions from Jupiter’s volcanic moon Io, allowing researchers to discover what triggers the strange radio waves. 

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Of all the planets in our solar system, Jupiter has the largest and most powerful magnetic field, which extends so far that some of the planet’s moons orbit within it. Because Io is closest to the planet, the moon is “caught in a gravitational tug-of-war” between Jupiter and two other large moons, according to NASA. These opposing pulls cause massive internal heat, which has led to hundreds of volcanic eruptions across the moon’s surface. 

The volcanos release 1 ton of gasses and particles per second into space, NASA said in a statement. Some of this material splits into electrically charged ions and electrons that then rain down onto Jupiter through the planet’s magnetic field. Electrons caught in the magnetic field are accelerated toward Jupiter’s poles and, along the way, generate a phenomenon scientists call decameter radio waves (also known as decametric radio emissions, or DAM). 

Related: Amazing photos: Jupiter’s volcanic moon Io

This conceptual image represents Jupiter's large, powerful magnetic field and how it links Io's orbit with Jupiter's atmosphere.
This conceptual image represents Jupiter’s large, powerful magnetic field and how it links Io’s orbit with Jupiter’s atmosphere. (Image credit: NASA/GSFC/Jay Friedlander)

When the spacecraft is in the right spot to listen, Juno’s Waves instrument can pick up these radio waves, Yasmina Martos of NASA’s Goddard Space Flight Center said in the statement. Researchers have used data from Juno to pinpoint where in Jupiter’s massive magnetic field the radio emissions come from. The data sheds light on the behavior of the enormous magnetic fields gas giants create. 

According to the research team, the radio waves come from space that can be described as a hollow cone, where the conditions are just right: the right magnetic field strength and the right density of electrons. The signal rotates like a lighthouse and Juno picks it up only when the “light” is shining on the spacecraft, according to the NASA statement. 

The radio data also showed that the electrons that create these radio waves emit a massive amount of energy, 23 times greater than researchers expected. Such electrons can come from other sources, too, such as from the planet’s magnetic field or from a solar wind, according to the research team. 

Time for Japan to get real on UFO intelligence sharing

With humans likely the threat, Tokyo needs to lend its eyes on the sky

People look at the night sky using night vision goggles during an UFO tour in the desert outside Sedona in the U.S. state of Arizona.  

TOKYO — Gone are the days when UFO stories were dismissed as crackpot pseudoscience. Today, they are an emerging field of public policy debate.

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A recent U.S. report on unidentified flying objects, or what the intelligence community calls unidentified aerial phenomena (UAP), has brought these mysterious sightings into the realm of serious discussion on national security.

The world’s powers need to take note. Japan and European allies of the U.S. should work on sharing information on UAP to learn more about them and assess potential security risks.

The report released on June 25 by the Office of the Director of National Intelligence examines 144 incidents of UAP gathered since 2004, mainly by the U.S. military. Most of them are from the past two years.

For many readers, the nine-page document raised more questions than it answered. Of the 144 reported UAP sightings, the Pentagon task force that examined the episodes could offer a reasonable explanation for only one case, identified as “a large, deflating balloon.” The rest remain unexplained.

In 18 incidents, unusual UAP movement patterns or flight characteristics were observed. “Some UAP appeared to remain stationary in winds aloft, move against the wind, maneuver abruptly, or move at considerable speed, without discernible means of propulsion,” according to the report. There are also 11 reports of near misses between the observing aircraft and a UAP.

The report is based on the work of the Department of Defense’s Unidentified Aerial Phenomena Task Force, set up in August 2020 in response to a flurry of UAP sightings in recent years. At a glance, the document seems to be a feast for UFO believers and conspiracy theorists. But far from being that, it reflects the growing interest in these phenomena among U.S. policymakers.ADVERTISING

After the release of the report, some U.S. lawmakers and security experts called for redoubled efforts to determine the truth behind UAP. “The United States must be able to understand and mitigate threats” posed by UAP, said Sen. Mark Warner, a Democrat from Virginia who serves as chairman of the Senate Select Committee on Intelligence.

Republican Sen. Marco Rubio of Florida concurred, saying, “The Defense Department and intelligence community have a lot of work to do before we can actually understand whether these aerial threats present a serious national security concern.”

The Pentagon is willing to respond to such calls. In late June, Deputy Secretary of Defense Kathleen Hicks directed the Office of the Under Secretary of Defense for Intelligence and Security to develop a plan to formalize the UAP task force’s activities.

A U.S. security expert with knowledge of discussions on this topic in the Biden administration said civilian and military officials are primarily worried that some aerial sightings may be linked to foreign countries or groups hostile to the U.S.

This is a more palpable threat than invading aliens. Even if intelligent life exists elsewhere in the vast universe, the sheer distances involved make it unlikely that such beings are visiting Earth at anywhere near the pace of reported UAP sightings.

Professor Hitoshi Murayama, a well-known theoretical particle physicist teaching at the University of California, Berkley, explained.

“Any planet with an environment similar to that of Earth is thought to be at least about four light years away from us,” Murayama said.

“Shuttling between such a planet and Earth would take an incredibly long time even with extremely sophisticated technology,” he said. “If extraterrestrial visitors are involved [in any of the UAP], it is hard to understand how they travel to the Earth so frequently.”

Existing earthly spaceships would take about 30,000 years to travel to a planet four light years away. Even for civilizations with far more advanced technology, the distance would be a daunting hurdle. These scientific assumptions support the view that UAP are human in origin. If so, at least some of the sightings may involve unknown highly advanced technology from countries like Russia or China, possibly representing a serious security threat to the U.S.

Multiple military experts warn that objects capable of the otherworldly flight characteristics reported in some UAP were used for military purposes, intercepting or tracking them with existing weapons systems would be next to impossible. Some UAP reports by the U.S. forces exhibit high-level stealth capabilities that defy radar detection.

The report mentions the possibility of “technologies deployed by China, Russia, another nation, or a nongovernmental entity.” But it admits there is no solid evidence to support such claims.

The report also suggests some UAP observations could be attributable to classified programs undertaken by the U.S. government or industry. If this is the case, however, such programs have been going on without the knowledge of top U.S. intelligence and defense officials.

The report does not necessarily rule out the involvement of alien visitors. Christopher Mellon, former deputy assistant secretary of defense for intelligence during the Clinton and George W. Bush administrations, argued for taking the alien theory seriously in a blog post on the UAP report.

“In my view, the UAP report’s findings strengthen the case for the alien hypothesis by undermining the main alternatives and providing examples of capabilities we cannot emulate or even understand,” Mellon said.

The topic should also raise security red flags for Japan and other U.S. allies that depend on the American military for their defense. Any technology unknown to the U.S. that defies responses by its military, whether human or extraterrestrial in origin, could pose a serious potential threat.

Closer cooperation between the U.S. and its allies on sharing and studying UAP sightings is essential. Most of the 144 UAP episodes covered by the report occurred in or around U.S. airspace.

If a foreign state or group is developing advanced weapons, chances are it will conduct more tests in other parts of the world rather than risk exposing its work to the Americans. If Russia or China were involved, Japan might be in a better geographical position than the U.S. to gather information about the technology.

Japan is beginning to take a minimum response to the challenge. Last September, one month after the U.S. set up the UAP task force, then Defense Secretary Taro Kono issued an unusual order to the Self-Defense Forces to take visual records and analyze such sightings.

During his meeting last summer with then-U.S. Defense Secretary Mark Esper, Kono raised the topic and agreed with the Pentagon chief to share information.

Traveling to space has become a thing among the world’s multibillionaires. This month, Virgin Group founder Richard Branson rode into space aboard a rocket he helped fund, followed less than two weeks later by Amazon.com founder Jeff Bezos.

But humans know only a sliver of the vast universe. While lawmakers and news media should still never feed wild alien conspiracy theories, the U.S. report has spelled the end of the taboo on discussing UFOs in the public policy sphere.

ESO captures best images yet of peculiar ‘dog-bone’ asteroid

Astronomers have obtained the sharpest and most detailed images yet of the asteroid Kleopatra. The observations have allowed the team to constrain the 3D shape and mass of this peculiar asteroid, which resembles a dog bone, to a higher accuracy than ever before. Their research provides clues as to how this asteroid and the two moons that orbit it formed.

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Using the European Southern Observatory’s Very Large Telescope (ESO’s VLT), a team of astronomers have obtained the sharpest and most detailed images yet of the asteroid Kleopatra. The observations have allowed the team to constrain the 3D shape and mass of this peculiar asteroid, which resembles a dog bone, to a higher accuracy than ever before. Their research provides clues as to how this asteroid and the two moons that orbit it formed.

“Kleopatra is truly a unique body in our Solar System,” says Franck Marchis, an astronomer at the SETI Institute in Mountain View, USA and at the Laboratoire d’Astrophysique de Marseille, France, who led a study on the asteroid — which has moons and an unusual shape — published today in Astronomy & Astrophysics. “Science makes a lot of progress thanks to the study of weird outliers. I think Kleopatra is one of those and understanding this complex, multiple asteroid system can help us learn more about our Solar System.”

Kleopatra orbits the Sun in the Asteroid Belt between Mars and Jupiter. Astronomers have called it a “dog-bone asteroid” ever since radar observations around 20 years ago revealed it has two lobes connected by a thick “neck.” In 2008, Marchis and his colleagues discovered that Kleopatra is orbited by two moons, named AlexHelios and CleoSelene, after the Egyptian queen’s children.advertisementMotegrity® (Prucalopride) – Official Physician SiteSee Motegrity Dosing and Administration Information at the Official Physician Site.www.motegrityhcp.com

To find out more about Kleopatra, Marchis and his team used snapshots of the asteroid taken at different times between 2017 and 2019 with the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instrument on ESO’s VLT. As the asteroid was rotating, they were able to view it from different angles and to create the most accurate 3D models of its shape to date. They constrained the asteroid’s dog-bone shape and its volume, finding one of the lobes to be larger than the other, and determined the length of the asteroid to be about 270 kilometres or about half the length of the English Channel.

In a second study, also published in Astronomy & Astrophysics and led by Miroslav Brož of Charles University in Prague, Czech Republic, the team reported how they used the SPHERE observations to find the correct orbits of Kleopatra’s two moons. Previous studies had estimated the orbits, but the new observations with ESO’s VLT showed that the moons were not where the older data predicted them to be.

“This had to be resolved,” says Brož. “Because if the moons’ orbits were wrong, everything was wrong, including the mass of Kleopatra.” Thanks to the new observations and sophisticated modelling, the team managed to precisely describe how Kleopatra’s gravity influences the moons’ movements and to determine the complex orbits of AlexHelios and CleoSelene. This allowed them to calculate the asteroid’s mass, finding it to be 35% lower than previous estimates.

Combining the new estimates for volume and mass, astronomers were able to calculate a new value for the density of the asteroid, which, at less than half the density of iron, turned out to be lower than previously thought [1]. The low density of Kleopatra, which is believed to have a metallic composition, suggests that it has a porous structure and could be little more than a “pile of rubble.” This means it likely formed when material reaccumulated following a giant impact.

Kleopatra’s rubble-pile structure and the way it rotates also give indications as to how its two moons could have formed. The asteroid rotates almost at a critical speed, the speed above which it would start to fall apart, and even small impacts may lift pebbles off its surface. Marchis and his team believe that those pebbles could subsequently have formed AlexHelios and CleoSelene, meaning that Kleopatra has truly birthed its own moons.

The new images of Kleopatra and the insights they provide are only possible thanks to one of the advanced adaptive optics systems in use on ESO’s VLT, which is located in the Atacama Desert in Chile. Adaptive optics help to correct for distortions caused by the Earth’s atmosphere which cause objects to appear blurred — the same effect that causes stars viewed from Earth to twinkle. Thanks to such corrections, SPHERE was able to image Kleopatra — located 200 million kilometres away from Earth at its closest — even though its apparent size on the sky is equivalent to that of a golf ball about 40 kilometres away.

ESO’s upcoming Extremely Large Telescope (ELT), with its advanced adaptive optics systems, will be ideal for imaging distant asteroids such as Kleopatra. “I can’t wait to point the ELT at Kleopatra, to see if there are more moons and refine their orbits to detect small changes,” adds Marchis.

Habitable Planets That Received Our Radio Signals And May Know We’re Here

We have been broadcasting for over 100 years. Now a new 3D map of the galaxy reveals the stars these signals have reached that can also see Earth.

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exoplanet - shutterstock 1052532938

(Credit: sdecoret/Shutterstock)

When Guglielmo Marconi made the first “long-distance” radio broadcasts in 1895, his assistant tuned into from a less than a kilometer away. Marconi went on to develop the world’s first commercial radio system and, by the time of his death in 1937, radio signals were routinely used to communicate across the world.

These broadcasts have also travelled into space, signaling to all who care to tune in, that humanity has emerged as a technologically advanced species. The first signals have now been travelling for over hundred years, reaching distances that would have been unimaginable to Marconi.

That raises some interesting questions about the stars these signals have already reached. What kind of stars are they, do they host exoplanets and if so, are any potentially Earth-like and in the habitable zone? How many of these exoplanets might also be able to see us?about:blankabout:blank

Now we get an answer thanks to the work of Lisa Kaltenegger at Cornell University in Ithaca and Jackie Faherty at the American Museum of Natural History in New York City. These astronomers have calculated the size of the sphere that our radio signals have covered since they left Earth, counted the stars that sit inside it and worked out which of them should also be able to see Earth transiting the Sun.

3D Star Map

All this is made possible by the Gaia Catalogue, a new 3D map of our galaxy showing the distance and motion of more than 100 million stars. The data comes from the European Space Agency’s Gaia spacecraft that was launched in 2013 and is mapping the position and motion of some 1 billion astronomical objects.

The resulting map is giving astronomers an entirely new way to study our galactic environment. Kaltenegger and Faherty’s project is a good example. Since Gaia measures how these stars are moving relative to one another, the researchers can work out for how long we have been visible to them and for how much longer.

Kaltenegger and Faherty say 75 stars systems that can see us, or soon will, sit within this 100 light year sphere. Astronomers have already observed exoplanets orbiting four of them.

These systems are generally well studied. The researchers say, for example, that the Ross128 star system is the 13th closest to the Sun and the second closest with a transiting Earth-size exoplanet. Then there is Teegarden’s Star, with at least two Earth-mass exoplanets and the Trappist-1 star system with seven Earth-sized planets, of which four are in the habitable zone.about:blankabout:blank

Our signals continue to radiate away from us. So Kaltenegger and Faherty also pick out at the star systems set to receive our signals in the next 200 years or so and will also be able to see us. “1,715 stars within 326 light-years are in the right position to have spotted life on a transiting Earth since early human civilization, with an additional 319 stars entering this special vantage point in the next 5,000 years,” they say.

Rocky Exoplanets

Exoplanet statistics suggest that at least 25 per cent of these stars will have rocky exoplanets. So there should be at least 508 rocky planets in this population with a good view of earth. “Restricting the selection to the distance radio waves from Earth have traveled- about 100 light-years – leads to an estimated 29 potentially habitable worlds that could have seen Earth transit and also detect radio waves from our planet,” say Kaltenegger and Faherty.

Of course, the possibility of life on these worlds is entirely unknown. The next generation of space telescopes should allow astronomers to study these worlds in more detail, to determine their atmospheric make up and perhaps see continents and oceans.

To similarly equipped alien eyes, Earth will have long looked an interesting target. Life first emerged here some 4 billion years ago, ultimately giving our atmosphere its rich oxygen content and its other biomarkers, such as methane. If astronomers find similar conditions elsewhere, that will pique their interest.

It could even prompt searches for radio signals that may already be reaching us from these places. Marconi would surely have been amazed.

Researchers Generate an Entire Virtual Universe and Make it Available for Download (if you Have 100 Terabytes of Free Hard Drive Space)

#Virtual #Universe

Astronomy is a bit different from many sciences because you only have a sample size of 1. The cosmos contains everything we can observe, so astronomers can’t study multiple universes to see how our universe ticks. But they can create computer simulations of our universe. By tweaking different aspects of their simulation, astronomers can see how things such as dark matter and dark energy play a role in our universe. Now, if you are willing to spring for a fancy hard drive, you can keep one of these simulations in your pocket.

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The Uchuu simulation is the largest and most detailed simulation of the universe ever made. It contains 2.1 trillion “particles” in a space 9.6 billion light-years across. The simulation models the evolution of the universe across more than 13 billion years. It doesn’t focus on the formation of stars and planets but instead looks at the behavior of dark matter within an expanding universe. The detail of Uchuu is high enough that the team can identify everything from galaxy clusters to the dark matter halos of individual galaxies. Since dark matter makes up most of the matter in the universe, it is the main driver of galaxy formation and clustering.

It takes a tremendous amount of computational power and storage to create such a detailed model. The team used over 40,000 computer cores and 20 million computer hours to generate their simulation, and it produced more than 3 Petabytes of data. That’s 3,000 Terabytes or 3 million Gigabytes for us mortals. Using high-density compression, however, the team was able to compress their results into a mere 100 Terabytes of storage.

That’s still a tremendous amount of data, but it can be stored on a single drive. For example, the Exadrive from Nimbus is a 100 Tb solid-state drive in a standard 3.5-inch form factor. Granted, it will set you back $40,000, but if you have that kind of change hiding between your couch cushions, why not use it to keep a universe in your pocket. Fortunately, if you don’t have that much spare change, you can access the data online. The Uchuu team has their raw data on skiesanduniverses.org, so you can explore their virtual universe all you want.

In addition to being a detailed cosmic simulation, the Uchuu simulation can be used by researchers working on scientific data mining. As large sky surveys and more simulations are created, the data will become so large data mining will play a crucial role in astronomical research. Until that data becomes available, data miners can hone their skills on a pocket universe.

One-kilometer-wide asteroid captured by radar observatory

NASA’s Goldstone 70-meter (230 foot) antenna captured radar imagery of asteroid 2016 AJ193 on Aug. 22, 2021 as it passed about 2.1 million miles (about 3.4 million kilometers) away from Earth.

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A gigantic asteroid that is considered potentially hazardous by NASA zipped past the Earth at a very high rate of speed. The asteroid, called 2016 AJ193, flew past the Earth at a velocity of 58,000 mph. It’s hard to imagine a speed that high; it equates to traveling about 16 miles every second.

NASA estimates the asteroid is about 4800 feet wide, approximately four times as wide as the Empire State building is tall. The asteroid passes through the solar system every six years on its orbit around the sun. Scientists are taking advantage of its proximity to the Earth on this orbit to study it in detail.

Astronomers observed the asteroid using radar, which is similar to the tech used for tracking thunderstorms on Earth. 2016 AJ193 Is a medium-size Apollo class asteroid. NASA says it’s comparable in size to the Pentagon. At its closest approach to Earth, it passed within 3,427,445 kilometers.

Anyone can tell that it was very far from our planet, but that is considered a close flyby on the astronomical scale of things. The asteroid has an elliptical orbit around the sun, and at its closest point, it’s 0.60 AU from the Sun, and at the furthest point of its orbit is 5.93 AU. An astronomical unit (AU) is the distance the Earth orbits from the sun.

The close approach that happened yesterday was one of only two coming in the near future. 2016 AJ193 will make its next near pass to the earth on August 19, 2080, when it will be 6,999,373 kilometers from Earth. It will have slowed down from its current velocity of 26.169 km/s to 21.713 km/s on that orbit.

NASA has too Many Spacecraft to Communicate With. Time to Build More Dishes

#NASA #Spacecraft #Communicate #Dish

NASA is a sprawling organization that has to talk to everything from politicians in Washington DC to space probes that have left the solar system.  Discussions with the first might be as simple as a written letter for informal conversation, while the second requires a high-power network of ground-based antennas.  Known as the Deep Space Network (DSN) this series of antennas spread over three continents is the backbone of NASA’s communications with its various space probes. Now the DSN is in the process of implementing a well-deserved upgrade.

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Part of the reason for that upgrade is the sheer number of spacecraft in deep space NASA has to communicate with.  Everything from Voyager to the Parker Solar Probe requires time on the antenna to relay data and receive instructions.  But with new missions launching at an increasing pace, the network must be beefed up in order to accommodate all the new communication links.

Currently, DSN supports 39 missions, but NASA has 30 additional missions in development, and not all of the existing missions will be phased out in the near future.  To ensure consistent communication no matter where the Earth is on its journey around the sun, the antennas supporting those 30 missions are evenly spread around the globe – in Madrid, Spain, Canberra, Australia, and near Barstow California. When not being used for communication directly, the antennas can serve as data collection platforms for radio science missions as well.

One major component of the upgrade needed to support all this work is the addition of 2 new antennas. The first, a 34-m wide dish named DSS-56 was commissioned in Madrid in January of this year. Also completed this year was an upgrade to DSS-43, a 70-m antenna located in Australia that is the only antenna in the Southern Hemisphere that is capable of sending messages to Voyager, which is currently outside of our solar system. 

DSS-43 won’t be the last 70-m antenna improvement either – its equivalents in Madrid and California are slated to receive upgrades soon as well.  Increasing the power of those antennas isn’t their only purpose.  With so much additional data being sent between handlers and spacecraft, increasing data transfer rates is another focal point of the network upgrades.  Eliminating frequency bands that specific telescopes are limited to will help the network utilize all of its resources to support all of its missions.  

Not only is the DSN getting technological upgrades, but it’s also trying a new management system that will better utilize the three sites spread throughout the world. Previously, on-site managers had managed the antennas at their site locally.  Now, there is a global hand-off protocol that managers call “Follow the Sun”, which allows personnel at each complex to run their entire network during their own “on” shift.  This has created cost savings as well as increased coordination between the sites as it requires regular knowledge transfer about local conditions and satellite quirks.  

Graphics posters showing the three 70-m antennas that are part of the DSN.
Graphics posters showing the three 70-m antennas that are part of the DSN.
Credit – NASA / JPL-Caltech

A lot of those cost savings from the new management architecture have gone into technological upgrades for the antennas themselves. With the pace of technological advancement in the communications field, there is plenty of room for improvement, but NASA has already shown that maintaining and even upgrading their internal communication network is one of the priorities.

Astronomers find evidence of an extragalactic exoplanet

#Astronomy #extragalactic #exoplanet #M51 #galaxy

The Milky Way is filled with planets. Now astronomers have found the first candidate planet in another galaxy.

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M51 Whirlpool Galaxy

The M51 Whirpool GalaxyNASA, ESA, S. Beckwith (STScI) and the Hubble Heritage Team (STScI/AURA)Since the first detection of the first exoplanet in 1992, astronomers have found thousands of others. Indeed, they estimate that the Milky Way is home to 40 billion worlds.

So it’s easy to imagine that planets must be common in other galaxies, particularly those that seem similar to our own. But when it comes to spotting these planets, there is a problem.

Other galaxies are so far away and the stars crammed into such a small region of space, as seen from Earth, that it is hard to identify individual ones let alone the effects of any planets around them. So extragalactic planets have sadly eluded astronomers.about:blank

Now Rosanne Di Stefano at the Harvard-Smithsonian Center for Astrophysics along with several colleagues, say they have found a candidate planet in the M51 Whirlpool Galaxy some 23 million light years from Earth near the constellation of Ursa Major. This alien world, christened M51-ULS-1b, is probably slightly smaller than Saturn and orbits a binary system at a distance of perhaps ten times Earth’s distance from the Sun.

The observation was possible because of a special set of conditions. The planet’s host binary system consists of a neutron star or black hole which is devouring a massive nearby star at a huge rate. The infall of stardust releases huge amounts of energy, making this system one of brightest sources of X-rays in the entire Whirlpool Galaxy. Indeed, its X-ray luminosity is roughly a million times brighter than the entire output of the Sun at all wavelengths.

X-Ray images

But the source of these X-rays — the black hole or neutron star — is tiny. That means a Saturn-sized planet orbiting a billion kilometers away can completely eclipse the X-ray source, should it pass directly in front in the line of sight with Earth.

On Sep. 20, 2012, that’s exactly what appears to have happened. Fortuitously, the orbiting Chandra X-ray Observatory was watching at the time. The X-ray source dimmed to nothing and then reappeared, the entire transit lasting about 3 hours.about:blank

At the time, nobody noticed because the data sets from Chandra weren’t being searched for such short variations. But when Di Stefano and colleagues looked, the tell tale signs were clear to see.

There are various reasons why an X-ray source can dim in this way. One is the presence of another small star, such as a white dwarf, that eclipses the X-ray source. The team says M51-ULS-1b cannot be a white dwarf or other type of star because the binary system is too young for such an object to have evolved nearby.

Another potential explanation is natural variation, perhaps because of an interruption to the material falling into the black hole or neutron star. Di Stefano and co say in these cases, the luminosity changes in a characteristic way, with higher energy light frequencies changing more quickly than lower energy ones, and switching back on in a different way.

Transit time

But in this case, all the light frequencies dimmed and reappeared at the same time, suggesting an eclipse. “It is approximately symmetric, and has a shape typical of transits in which the source and transiting object have comparable size,” they say.about:blank

Now that the first planet candidate in another galaxy has emerged, Di Stefano and co say others are likely to be found quickly. The team scoured just a portion of the X-ray data from Chandra to find this new planet candidate.

There is plenty more where that data came from. “The archives contain enough data to conduct surveys comparable to ours more than ten times over,” say the team. “We therefore anticipate the discovery of more than a dozen additional extragalactic candidate planets in wide orbits.” And more data is being gathered all the time.

So while M51-ULS-1b may be the first candidate planet discovered in another galaxy, it is unlikely to be the last. Just watch this space.

Asteroid dust found at Chicxulub Crater confirms cause of dinosaurs’ extinction

 The impact site (Southern North America) of the asteroid that killed the dinosaurs 65 million years ago – It is called the Chicxulub Crater ~ 200 Km in diameter.

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Asteroid dust found at Chicxulub Crater confirms cause of dinosaurs’ extinction

Although an asteroid impact has long been the suspected cause of the mass extinction 66 million years ago, researchers think new evidence finally closes the case.


An asteroid smashed into the Yucatán Peninsula 66 million years ago, killing some 75 percent of life on Earth, including all non-avian dinosaurs.Willgard Krause/Pixabay

Some 66 million years ago, a city-size asteroid barreled through Earth’s atmosphere and slammed into the shallow waters off the Yucatán Peninsula in the Gulf of Mexico. The cosmic artillery strike gouged a 125-mile-wide (200 km) crater in Earth surface, lofting plumes of vaporized rock and debris into the air that globally blocked out views of the Sun for years or decades. After the initial blast, the reduced sunlight caused Earth’s surface temperature to plummet by as much as 50 degrees Fahrenheit (28 degrees Celsius), aiding in a mass extinction that killed 75 percent of life on Earth.

But eventually, the dust settled.

Fast forward to the 1980s, and scientists uncovered traces of asteroid dust, finding it scattered around the globe within the same geological layer that corresponds to the dinosaurs’ extinction. In the following decade, Chicxulub Crater was discovered in the Gulf of Mexico. And because the crater appeared to be the same age as the global rock layer enriched with asteroid dust, researchers were fairly certain they had the story of the dinosaurs’ demise figured out.about:blankabout:blank

Now, a new study seems to have officially closed the case for good.


Named after a nearby town, Chicxulub crater is located just offshore. New evidence confirms the site is almost undoubtedly the epicenter of the dinosaurs’ demise.The University of Texas at Austin/Jackson School of Geosciences/Google MapsThe latest evidence comes from rock core samples plucked from Chicxulub Crater itself, which is buried beneath the seafloor in the Gulf of Mexico. In the most recent study based on these samples, which were collected during a 2016 mission co-led by the University of Texas at Austin, researchers say they’ve found a telltale sign of asteroid dust. It comes in the form of iridium, which is common in some types of asteroids, yet rare in Earth’s crust.

The researchers found the highest concentration of iridium-peppered rock, which also contains a mixture of ash from the impact and ocean sediment, within a sample taken from the crater’s peak ring. This sample likewise shows elevated levels of other elements commonly associated with asteroids, resulting in a chemical fingerprint that resembles the asteroid dust found around the globe in the 1980s, and precisely matches the geological location of the impact itself.


Seen here is the section of rock core from Chicxulub Crater in which researchers found a concentration of iridium, a tracer for asteroid material, mixed with ash from the impact and ocean sediment.The International Ocean Discovery Program.We combined the results from four independent laboratories around the world to make sure we got this right,” said lead author Steven Goderis, a geochemistry professor at Vrije Universiteit Brussel, in a press release.

“We are now at the level of coincidence that geologically doesn’t happen without causation,” added Sean Gulick, a professor at UT Jackson School of Geoscience and co-author of the study.

Giant Comets Pose a Greater Threat to Earth Than Asteroids

Astronomers Say Giant Comets Pose a Greater Threat to Earth Than Asteroids

A team of astronomers has identified giant comets as a greater threat to life on Earth than asteroids. The biggest difference between the two celestial bodies is their composition: comets are composed of ice, dust, and rock, whereas asteroids are made up of metals and rock – which is why comets leave a ‘tail’, as the ice within them gets vapourised by the Sun.

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That distinction might not mean much to the average resident of planet Earth, but another major difference between comets and asteroids is where they can be found in the Universe. Giant comets, known as centaurs (around 50-100 km or 31-62 miles across), move through unstable orbits that take them past the larger planets: Jupiter, Saturn, Uranus, and Neptune.

The gravity from these planets can deflect comets in the direction of Earth, and we’re discovering more and more of these centaurs as time goes on.

Researchers from Armagh Observatory and the University of Buckingham in the UK think this makes them a genuine threat to our home planet – more so than the asteroids that typically come closer to Earth on a regular basis, and which have been the main focus of NASA’s investigations so far.

If a centaur heading in our direction should break up into pieces, we could face an intermittent bombardment of missiles that lasts 100,000 years, according to the new report.

“In the last three decades we have invested a lot of effort in tracking and analysing the risk of a collision between Earth and an asteroid,” said one of the team, astronaut Bill Napier. “Our work suggests we need to look beyond our immediate neighbourhood too, and look out beyond the orbit of Jupiter to find centaurs. If we are right, then these distant comets could be a serious hazard, and it’s time to understand them better.”

Based on a study of ancient civilisations, the terrestrial environment and interplanetary matter close to Earth, the scientists think the remnants of a centaur may have hit our planet some 30,000 years ago. Based on a projected frequency of one centaur per 40,000 to 100,000 years, that means we’re almost due for another one.

The cratering patterns found on Earth and the Moon suggest the volume of near-Earth objects (NEOs) is episodic in nature, say the researchers. In other words, it varies significantly over time, and we should be prepared for another sudden increase in the number and frequency of the NEOs we potentially have to deal with. Perhaps the sooner we all vacate the planet, the better.

The study has been published in the journal Astronomy & Geophysics.

AI discovers new craters on Mars in just five seconds

#mars #crater #AI

It could analyze a photo of the Martian surface in just five seconds. NASA scientists need 40 minutes.

If you’ve ever played one of those “spot the difference between these two photos” games, you have something in common with NASA scientists.

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To identify newly formed craters on Mars, they’ll spend about 40 minutes analyzing a single photo of the Martian surface taken by the Context Camera on NASA’s Mars Reconnaissance Orbiter (MRO), looking for a dark patch that wasn’t in earlier photos of the same location.

If a scientist spots the signs of a crater in one of those images, it then has to be confirmed using a higher-resolution photograph taken by another MRO instrument: the High-Resolution Imaging Science Experiment (HiRISE).

This method of spotting new craters on Mars makes it easy to determine an approximate date for when each formed — if a crater wasn’t in a photo from April 2016 but is in one from June 2018, for example, the scientists know it must have formed sometime between those two dates.

By studying the characteristics of the craters whose ages they do know, the scientists can then estimate the ages of older ones. This information can improve their understanding of Mars’ history and help with the planning of new missions to the Red Planet.

The problem: this is incredibly time-consuming.

The MRO has been taking photos of the Red Planet’s surface for 15 years now, and in that time, it has snapped 112,000 lower-resolution images, with each covering hundreds of miles of the Martian surface.

To free scientists from the burden of manually analyzing all those photos, researchers trained an algorithm to scan the same images for signs of new craters on Mars — and it only needs about five seconds per picture.

Fresh craters on Mars

To train their image-analyzing AI to spot new craters on Mars, the researchers started by feeding it nearly 7,000 images from the Context Camera. Some featured fresh craters confirmed by HiRISE photos, and others didn’t.

After training, the next step was letting the algorithm analyze all of the Context Camera images.

This is just beginning. We’re looking forward to finding a lot more.


To speed it up, the researchers ran the AI on a supercomputer cluster at NASA’s Jet Propulsion Laboratory (JPL).

“It wouldn’t be possible to process over 112,000 images in a reasonable amount of time without distributing the work across many computers,” JPL computer scientist Gary Doran said in October. “The strategy is to split the problem into smaller pieces that can be solved in parallel.”

With the power of all those computers combined, the AI could scan an image in an average of just five seconds. If it flagged something that looked like a fresh crater, NASA scientists could then check it out themselves using HiRISE.

Scanning the Martian surface

In October, NASA confirmed that the AI had discovered its first fresh craters on Mars, and to date, it’s helped scientists spot dozens of new impacts in the Context Camera images.

“The data was there all the time,” JPL computer scientist Kiri Wagstaf told Wired. “It’s just that we hadn’t seen it ourselves.”

In the future, the AI might help scientists identify more craters on Mars — potentially within weeks of their formation — or even craters on other planets.

“The possibility of using machine learning to really delve into large data sets and find things that we otherwise wouldn’t have found is really exciting,” Ingrid Daubar, a planetary scientist who helped create the AI, told Wired.

“This is just beginning,” she added. “We’re looking forward to finding a lot more.”

Why is this weird, metallic star hurtling out of the Milky Way?

Astronomers analyzed light data from a piece of supernova shrapnel to gain clues about where it came from.

About 2,000 light-years away from Earth, there is a star catapulting toward the edge of the Milky Way. This particular star, known as LP 40?365, is one of a unique breed of fast-moving stars — remnant pieces of massive white dwarf stars — that have survived in chunks after a gigantic stellar explosion.

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“This star is moving so fast that it’s almost certainly leaving the galaxy…[it’s] moving almost two million miles an hour,” says JJ Hermes, Boston University College of Arts & Sciences assistant professor of astronomy. But why is this flying object speeding out of the Milky Way? Because it’s a piece of shrapnel from a past explosion — a cosmic event known as a supernova — that’s still being propelled forward.

“To have gone through partial detonation and still survive is very cool and unique, and it’s only in the last few years that we’ve started to think this kind of star could exist,” says Odelia Putterman, a former BU student who has worked in Hermes’ lab.

In a new paper published in The Astrophysical Journal Letters, Hermes and Putterman uncover new observations about this leftover “star shrapnel” that gives insight to other stars with similar catastrophic pasts.

Putterman and Hermes analyzed data from NASA’s Hubble Space Telescope and Transiting Exoplanet Survey Satellite (TESS), which surveys the sky and collects light information on stars near and far. By looking at various kinds of light data from both telescopes, the researchers and their collaborators found that LP 40?365 is not only being hurled out of the galaxy, but based on the brightness patterns in the data, is also rotating on its way out.

“The star is basically being slingshotted from the explosion, and we’re [observing] its rotation on its way out,” says Putterman, who is second author on the paper.

“We dug a little deeper to figure out why that star [was repeatedly] getting brighter and fainter, and the simplest explanation is that we’re seeing something at [its] surface rotate in and out of view every nine hours,” suggesting its rotation rate, Hermes says. All stars rotate — even our sun slowly rotates on its axis every 27 days. But for a star fragment that’s survived a supernova, nine hours is considered relatively slow.

Supernovas occur when a white dwarf gets too massive to support itself, eventually triggering a cosmic detonation of energy. Finding the rotation rate of a star like LP 40?365 after a supernova can lend clues into the original two-star system it came from. It’s common in the universe for stars to come in close pairs, including white dwarfs, which are highly dense stars that form toward the end of a star’s life. If one white dwarf gives too much mass to the other, the star being dumped on can self-destruct, resulting in a supernova. Supernovas are commonplace in the galaxy and can happen in many different ways, according to the researchers, but they are usually very hard to see. This makes it hard to know which star did the imploding and which star dumped too much mass onto its star partner.

Based on LP 40?365’s relatively slow rotation rate, Hermes and Putterman feel more confident that it is shrapnel from the star that self-destructed after being fed too much mass by its partner, when they were once orbiting each other at high speed. Because the stars were orbiting each other so quickly and closely, the explosion slingshotted both stars, and now we only see LP 40-365.

“This [paper] adds one more layer of knowledge into what role these stars played when the supernova occurred,” and what can happen after the explosion, Putterman says. “By understanding what’s happening with this particular star, we can start to understand what’s happening with many other similar stars that came from a similar situation.”

“These are very weird stars,” Hermes says. Stars like LP 40-365 are not only some of the fastest stars known to astronomers, but also the most metal-rich stars ever detected. Stars like our sun are composed of helium and hydrogen, but a star that has survived a supernova is primarily composed of metal material, because “what we’re seeing are the by-products of violent nuclear reactions that happen when a star blows itself up,” Hermes says, making star shrapnel like this especially fascinating to study.

Scientists find chunk of blown-apart star hurtling through Milky Way at breakneck speed

LP 40-365 will probably leave the galaxy at some point, scientists say.

Artist’s impression of a supernova ejecting a white dwarf star.

Artist’s impression of a supernova ejecting a white dwarf star. (Image credit: Mark Garlick / Science Photo Library via Getty Images )

A chunk of stellar shrapnel is careering toward the edge of our Milky Way galaxy at almost 2 million mph (3.2 million kph), a new study reports.

“The star is moving so fast that it’s almost certainly leaving the galaxy,” study co-lead author J.J. Hermes, an associate professor of astronomy at Boston University, said in a statement

The star, known as LP 40-365, currently lies about 2,000 light-years from Earth. And calling it a star may be a bit generous, actually; Hermes and his colleagues think it’s a hunk of a superdense stellar corpse called a white dwarf that was blown apart in a violent supernova explosion after gobbling up too much mass from a companion. 

“To have gone through partial detonation and still survive is very cool and unique, and it’s only in the last few years that we’ve started to think this kind of star could exist,” study co-author Odelia Putterman, a former Boston University student who has worked in Hermes’ lab, said in the same statement. 

The speedy star was spotted during an analysis of survey data gathered by NASA’s Hubble Space Telescope and Transiting Exoplanet Survey Satellite (TESS). The researchers noticed that LP 40-365is not only racing along but is also rotating once every nine hours as it goes. 

The rotation in itself is nothing unusual, for all stars rotate; our own sun spins on its axis every 27 Earth days. However, according to researchers, a nine-hour rotational period is considered to be relatively slow for an object that went through something as catastrophic as a supernova. 

It’s this sluggish rotation that implies LP 40-365 was once part of a two-star system with an unhealthy feeding habit. 

According to the researchers, stars commonly orbit each other in close pairs, including highly dense white dwarfs. In such binary systems, if one white dwarf transfers too much mass to the other, the result can be a supernova — the largest explosion that takes place in space, according to NASA.

It’s usually hard to determine which star was the “donor” and which was the “eater.” But because LP 40-365’s rotation is relatively slow, the research team feels confident that the object is cosmic shrapnel from the exploded star. As the two stars orbited each other at high speeds and in close proximity, the resulting supernova likely catapulted both stars out at breakneck speed, but we’ve only been able to spot LP 40-365, according to the statement.

“This [paper] adds one more layer of knowledge into what role these stars played when the supernova occurred,” and what can happen after the explosion, Putterman said. “By understanding what’s happening with this particular star, we can start to understand what’s happening with many other similar stars that came from a similar situation.”

These supernova survivors are even more intriguing as they are metal-rich, unlike our sun, which is primarily composed of hydrogen and helium. (Astronomers consider any element heavier than hydrogen and helium a metal.)

“These are very weird stars,” Hermes said. “What we’re seeing are the byproducts of violent nuclear reactions that happen when a star blows itself up.” Strange stars like LP 40-365 are therefore fascinating targets to study, the researchers said. 

Great conjunctions between Saturn and Jupiter Moon are rare

Great conjunctions between Saturn and Jupiter Moon are rare, the next easily observable conjunction of the two planets is not expected for nearly 40 years.

#jupiter #saturn #astronomy #space #nasa #universe #astrophotography #science #cosmos #moon #stars #galaxy #astrophysics #nightsky #physics #photography #spacex #milkyway #cosmology #astro #earth #astronomia #sky #nature #telescope #astronaut #nightphotography #solarsystem #planets #night #mars

NASA probe snaps ‘great conjunction’ photo of Jupiter and Saturn from the moon

Behold, the view from the Lunar Reconnaissance Orbiter!

The Lunar Reconnaissance Orbiter captured an image of 2020's great conjunction of Jupiter and Saturn.
(Image credit: NASA/GSFC/Arizona State University)

A moon-orbiting probe got a stunning up-close view of the “great conjunction” of Jupiter and Saturn from Earth’s rocky satellite. 

Jupiter and Saturn appeared closer in the night sky than they had in about 800 years during what’s known as a “great conjunction.” People all around the globe watched and photographed the planets, which looked almost like a single, bright “star” in the sky. However, us Earthlings weren’t the only ones who got a celestial show. 

NASA’s Lunar Reconnaissance Orbiter (LRO), which launched in 2009 and has enough fuel to keep orbiting the moon for another six years, spotted the cosmic event all the way from the moon. 

The Lunar Reconnaissance Orbiter Camera’s (LROC) Narrow Angle Camera (NAC) captured an unbelievable image of the two planets just a few hours after the pair’s point of closest separation (0.1 degrees). Now, while Jupiter and Saturn may have looked like one glowing orb to the naked eye, with the detailed view of the NAC, you can clearly resolve the individual planets. In fact, the image provides so much detail that you can even faintly see Saturn’s rings. 

Here on Earth, skywatchers were able to see Jupiter’s moons with DSLR cameras and even basic telescopes, though Saturn’s rings were usually only visible with higher-powered telescopes. 

On Dec. 21, 2020, Jupiter and Saturn will appear just one-tenth of a degree apart, or about the thickness of a dime held at arm's length, according to NASA. During the event, known as a "great conjunction," the two planets (and their moons) will be visible in the same field of view through binoculars or a telescope.
On Dec. 21, 2020, Jupiter and Saturn appeared just one-tenth of a degree apart, or about the thickness of a dime held at arm’s length, according to NASA. During the event, known as a “great conjunction,” the two planets (and their moons) were visible in the same field of view through binoculars or a telescope.  (Image credit: NASA/JPL-Caltech)

When the NAC captured this image of the two planets, Jupiter was about four times brighter than Saturn, so the brightness of the original image was adjusted to make both equally visible. 

While Jupiter and Saturn have a close conjunction once every 20 years, the planets haven’t appeared this close since 1623. Additionally, the planetary alignment came just a few days before Christmas, with many dubbing the bright event a “Christmas Star,” adding even more to the astronomical excitement. 

Interstellar comets like Borisov may not be all that rare

#Interstellar #comet #Borisov #asteroid #space #astronomy

Astronomers calculate that the Oort Cloud may be home to more visiting objects than objects that belong to our solar system.

In 2019, astronomers spotted something incredible in our backyard: a rogue comet from another star system. Named Borisov, the icy snowball traveled 110,000 miles per hour and marked the first and only interstellar comet ever detected by humans.

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But what if these interstellar visitors — comets, meteors, asteroids and other debris from beyond our solar system — are more common than we think?

In a new study published Monday in the Monthly Notices of the Royal Astronomical Society, astronomers Amir Siraj and Avi Loeb at the Center for Astrophysics | Harvard & Smithsonian (CfA) present new calculations showing that in the Oort Cloud — a shell of debris in the farthest reaches of our solar system — interstellar objects outnumber objects belonging to our solar system.

“Before the detection of the first interstellar comet, we had no idea how many interstellar objects there were in our solar system, but theory on the formation of planetary systems suggests that there should be fewer visitors than permanent residents,” says Siraj, a concurrent undergraduate and graduate student in Harvard’s Department of Astronomy and lead author of the study. “Now we’re finding that there could be substantially more visitors.”

The calculations, made using conclusions drawn from Borisov, include significant uncertainties, Siraj points out. But even after taking these into consideration, interstellar visitors prevail over objects that are native to the solar system.

“Let’s say I watch a mile-long stretch of railroad for a day and observe one car cross it. I can say that, on that day, the observed rate of cars crossing the section of railroad was one per day per mile,” Siraj explains. “But if I have a reason to believe that the observation was not a one-off event — say, by noticing a pair of crossing gates built for cars — then I can take it a step further and begin to make statistical conclusions about the overall rate of cars crossing that stretch of railroad.”

But if there are so many interstellar visitors, why have we only ever seen one?

We just don’t have the technology to see them yet, Siraj says.

Consider, he says, that the Oort Cloud spans a region some 200 billion to 10 trillion miles away from our Sun — and unlike stars, objects in the Oort Cloud don’t produce their own light. Those two factors make debris in the outer solar system incredibly hard to see.

Senior astrophysicist Matthew Holman, who was not involved in the research, says the study results are exciting because they have implications for objects even closer than the Oort Cloud.

“These results suggest that the abundances of interstellar and Oort cloud objects are comparable closer to the Sun than Saturn. This can be tested with current and future solar system surveys,” says Holman, who is the former director of the CfA’s Minor Planet Center, which tracks comets, asteroids and other debris in the solar system.

“When looking at the asteroid data in that region, the question is: are there asteroids that really are interstellar that we just didn’t recognize before?” he asks.

Holman explains that there are some asteroids that get detected but aren’t observed or followed up on year after year. “We think they are asteroids, then we lose them without doing a detailed look.”

Loeb, study co-author and Harvard astronomy professor, adds that “interstellar objects in the planetary region of the solar system would be rare, but our results clearly show they are more common than solar system material in the dark reaches of the Oort cloud.”

Observations with next-generation technology may help confirm the team’s results.

The launch of the Vera C. Rubin Observatory, slated for 2022, will “blow previous searches for interstellar objects out of the water,” Siraj says, and hopefully help detect many more visitors like Borisov.

The Transneptunian Automated Occultation Survey (TAOS II), which is specifically designed to detect comets in the far reaches of our solar system, may also be able to detect one of these passersby. TAOS II may come online as early as this year.

The abundance of interstellar objects in the Oort Cloud suggests that much more debris is left over from the formation of planetary systems than previously thought, Siraj says.

“Our findings show that interstellar objects can place interesting constraints on planetary system formation processes, since their implied abundance requires a significant mass of material to be ejected in the form of planetesimals,” Siraj says. “Together with observational studies of protoplanetary disks and computational approaches to planet formation, the study of interstellar objects could help us unlock the secrets of how our planetary system — and others — formed.”

First Ever FRB That Repeats Every 16 Days Gets More Mysterious

What’s creating these unusual signals? And why does this one repeat itself?

A photo shows the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project at night.

A photo shows the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project at night. (Image credit: CHIME FRB)

One of the universe’s deep mysteries just got a lot stranger. Astrophysicists have discovered a clue that could help explain why, every once in a while, superfast bursts of radio waves flash across Earth from deep space. But the clue — a repeating 16-day pattern in one of the bursts, undermines one of the most popular theories for where the bursts are coming from.

#FRB #fastradioburst #space #astronomy #CHIME

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Fast radio bursts (FRBs) have likely happened for billions of years. But humans only discovered them in 2007, and have detected only a few dozen of them since. And in June 2019, astronomers finally tracked an FRB to its home galaxy

But no one knows what causes them. Because these bursts are so rare, unusual and bright — considering that they’re visible from billions of light-years across space — physicists have tended to assume they come from a cataclysmic event, such as the collision of stars.

This repeating pattern, however, suggests that something else is going on, that there’s some sort of natural machine in the universe for pumping regular shrieks of radio energy across space.

Researchers looking at data from the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project (CHIME/FRB) first spotted this FRB, known as FRB 180916.J0158+65, in 2019. In January 2020, they published a paper in the journal Nature that reanalyzed old data and found more than one burst from FRB 180916.J0158+65. They traced this FRB back to a relatively nearby spiral galaxy. What’s new in this latest paper, published Feb. 3 to the arXiv database, is the regular pattern in the bursts. The FRB, they found, goes through four-day cycles of regular activity, bleating out radio waves into space on an almost hourly basis. Then it goes into a 12-day period of silence. Sometimes the source seems to skip its usual four-day awake periods, or lets out only a single burst. CHIME/FRB is able to watch the FRB only some of the time, they noted, so it’s likely the detector misses many FRBs during the awake period.

No one knows what this pattern means, the researchers noted in a statement, but this pattern doesn’t fit neatly into any existing explanations for FRBs.

In general, patterns like this in astrophysics are often related to a spinning object or orbiting celestial bodies. Neutron stars often seem to strobe regularly from the perspective of X-ray detectors on Earth, because hot spots on their surface spin in and out of view like a lighthouse beacon. And tiny planets may dim the light of the stars they orbit everytime they pass between that star and Earth.

In other words, for astrophysics, patterns tend to indicate rotation. But no one knows if this pattern governs all FRBs or just some of them. 

Cracking a mystery about Vesta, our solar system’s second largest asteroid

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#Vesta #asteroid #troughs #space #astronomy

How did the troughs form?

Cracking a mystery about Vesta, our solar system’s second largest asteroid

Dawn’s last look at the asteroid VestaCredit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDAVesta is the second largest asteroid in our solar system and believed to be a proto-planet. NASA’s Dawn spacecraft visited Vesta in 2011.The mission revealed two massive impact craters and some odd troughs encircling them.

The asteroid Vesta is the second largest asteroid in the solar system’s asteroid belt, with a diameter of about 330 miles. (Ceres is the biggest.) It is the brightest asteroid up there, too, sometimes visible to the naked eye from Earth. Astronomers consider it a planetesimal because, like a mini-Earth, it has an iron core and rock in its crust and mantle.

The asteroid has long been an object of interest to star-gazers. The first book Isaac Asimov published was called Marooned off Vesta, and in 2011, the NASA spacecraft Dawn paid it a visit on its way to Ceres.

Dawn found two massive impact craters on Vesta — Rheasilvia and Veneneia — evidence of collisions large enough that they ejected about one percent of Vesta out into space. Indeed, roughly six percent of the meteorites we have found on Earth come from Vesta. Dawn also observed that there are two enormous troughs roughly around Rheasilvia and Veneneia. It has been assumed that they are somehow related to the two giant impacts.

A new study revisits this assumption and proposes a novel hypothesis about what exactly these mysterious troughs are.

Counting craters

Vesta’s topography, color-enhanced, from Dawn.Credit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDA / PSI

If the troughs were produced by the Rheasilvia and Veneneia impacts, then they must be roughly the same age as the craters. Counting craters is one way to determine age.

“Our work used crater-counting methods to explore the relative age of the basins and troughs,” says co-author Jupiter Cheng. Since a newly formed body is free of impact craters, one can estimate its age by counting the number of craters present. While this is obviously an imprecise way of figuring out the absolute age of an asteroid, it is useful for determining the relative age of specific features. If the features are surrounded by a similar number of impacts, they are probably roughly the same age.

“Our result,” says Cheng, “shows that the troughs and basins have a similar number of the crater of various sizes [sic], indicating they share a similar age. However, the uncertainties associated with the crater counts allow for the troughs to have formed well after the impacts.”

This timeline fits with the researcher’s proposed explanation for the troughs.

Low gravity and the troughs

Credit: University of Georgia / NASA / JPL

It has been assumed, says Cheng, that the “troughs are fault-bounded valleys with a distinct scarp on each side that together mark the down-drop (sliding) of a block of rock.”

However, there is a problem with this theory. It is based on the way rocks and debris behave under the force of gravity on Earth; Vesta’s gravitational pull is far less. Indeed, Dawn found Vesta’s gravity consistent with an iron core having a 140-mile diameter; the Earth’s, by comparison, is about 2,165 miles in diameter.

Cheng notes that “rock can also crack apart and form such troughs, an origin that has not been considered before. Our calculations also show that Vesta’s gravity is not enough to induce surrounding stresses favorable for sliding to occur at shallow depths. Instead, the physics shows that rocks there are favored to crack apart.”

Cheng summarizes, “Taken all together, the overall project provides alternatives to the previously proposed trough origin and geological history of Vesta, results that are also important for understanding similar landforms on other small planetary bodies elsewhere in the solar system.”

So while still consistent with the prevailing theory that the impacts resulted in the troughs, the researchers suggest that they did not cause landslides on Vesta. The impacts cracked it.

What NASA Discovered on Jupiter’s Moon Callisto

#Callisto #Jupiter #Moon #space #astronomy


Voyager 1 image of Jupiter’s moon Callisto from a distance of 350,000 km. The large ‘bulls-eye’ at the top is believed to be an impact basin formed early in Callisto’s history. The bright center of the basin is about 600 km across and the outer ring is about 2,600 km across. (Image credit: NASA/NSSDC Photo Gallery)

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Callisto is a large moon orbiting Jupiter. It has an ancient, cratered surface, indicating that geological processes could be dead. However, it may also hold an underground ocean. It’s unclear if the ocean could have life in it because the surface is so old. It will take more observation of this large moon to be absolutely sure.

The moon has been a subject of several flybys, including the long-running Galileo mission at Jupiter in the 1990s and 2000s. An upcoming mission called JUICE (Jupiter Icy Moon Explorer) will focus on three icy Jupiter moons, including Callisto, to get more information about its environment. JUICE is expected to arrive in 2030.

NASA has a mission at Jupiter right now called Juno. While Juno is more designed to look at the atmosphere and environment of Jupiter, it has taken some images of Callisto from a distance

Several icy moons of the solar system have been a focus of exploration in recent years because of their potential for holding life. The Cassini spacecraft, which orbited Saturn from 2004 to 2017, uncovered extensive evidence of geysers at its moon, Enceladus. Other icy moons include Triton (at Neptune, imaged by Voyager 2) and Europa (another icy moon of Jupiter.) In general, these moons maintain liquid oceans because of the gravitational tug from their large giant planets.


Jupiter’s four largest moons — Io, Europa, Ganymede and Callisto — are also known as the Galilean moons, named after Galileo Galilei, who discovered them in 1610. All four are bigger than Pluto, and Ganymede is the largest moon in the solar system, even bigger than Mercury. [Photos: The Galilean Moons of Jupiter]

When Galileo turned his telescope to Jupiter on Jan. 7, 1610, what he saw surprised everybody. The planet was not alone; it had four moons circling it. At the time, it was believed that the Earth was the only planet with a moon. For two centuries Jupiter’s moons were (as a group) named after the Medicis, a powerful Italian political family, according to NASA. Individually they were called Jupiter I, II, III and IV, with “IV” referring to what we now call Callisto.

The discovery had not only astronomical, but also religious implications. At the time, the Catholic Church supported the idea that everything orbited the Earth, an idea put forth in ancient times by Aristotle and Ptolemy. Galileo’s observations of Jupiter’s moons — as well as noticing that Venus went through “phases” similar to our own moon — gave compelling evidence that not everything revolved around the Earth. 

As telescopic observations improved, however, a new view of the universe emerged. The moons and the planets were not unchanging and perfect; for example, mountains seen on the moon showed that geological processes happened elsewhere. Also, all planets revolved around the sun. Over time, moons around other planets were discovered — and additional moons found around Jupiter. The Medici moons were renamed Io, Europa, Ganymede and Callisto to avoid confusion by the mid-1800s.

Basic facts

Age: Callisto is about 4.5 billion years old, about the same age as Jupiter. It is the most heavily cratered object in the solar system, according to NASA. There is hardly any geologic activity on its surface. The surface has not changed much since initial impacts molded its surface 4 billion years ago.

Distance from Jupiter: It is the outermost of the Galilean moons. Callisto orbits Jupiter at a distance of about 1,168,000 miles (1,880,000 kilometers). It takes the moon about seven Earth-days to make one complete orbit of the planet. It also experiences fewer tidal influences than the other Galilean moons because it orbits beyond Jupiter’s main radiation belt. Callisto is tidally locked, so the same side always faces Jupiter.

Size: At 3,000 miles (4,800 km) in diameter, Callisto is roughly the same size as Mercury. It is the third largest moon in the solar system, after Ganymede and Titan. (Earth’s moon is fifth largest, following Io.) 

Temperature: The mean surface temperature of Callisto is minus 218.47 degrees Fahrenheit (minus 139.2 Celsius).

Space-age observations

While telescopes improved substantially by the Space Age of the 1960s, still little was known about Callisto, according to the 2004 book “Jupiter: The Planet, Satellites and Magnetosphere” (Cambridge, 2007). From what astronomers could tell, the surface looked relatively featureless compared with Io and Ganymede. Callisto also had low reflectivity (albedo) and was known to have a low density, but astronomers saw no evidence of water emissions. This led them to conclude that Callisto had a rocky surface.

Pioneer 10 and Pioneer 11 each flew by Jupiter and its moons in the early 1970s, but these missions didn’t give much new information on Callisto beyond what Earth-based telescopes showed. It was the Voyager missions of the late 1970s that really showed us a different picture of the moon. Callisto’s density and temperature were refined, and images of the surface showed features as small as 1 kilometer per pixel — in other words, a resolution small enough to spot impact craters. In fact, Callisto was very heavily cratered compared with the other moons, the authors wrote. “Some dismissed Callisto as the most boring object of its size in the solar system,” they added.

More close-up observations required a wait until 1996, when the Galileo spacecraft commenced the first of 12 flybys of the moon. Galileo’s repeated flybys and higher resolution revealed much more information about Callisto than before. More of the surface was mapped, a thin carbon dioxide atmosphere was discovered, and evidence of a subsurface ocean was uncovered. 

Arguments for an ocean came from two pieces of evidence, according to NASA. First, scientists saw regular fluctuations of Callisto’s magnetic field as the moon circled Jupiter, which implied there were electrical currents within the moon stimulated by the planet’s magnetic field. That current had to conduct from somewhere, which led to the second piece: due to the rocky surface and thin atmosphere, a likely explanation would be a salty ocean under the moon’s surface.Advertisement

In 2018, examinations of archival images taken by the Hubble Space Telescope in 2007 showed Callisto’s effect on auroral bursts in Jupiter’s atmosphere. Jupiter generates auroras on its own, but some of the phenomena come through interactions with its four largest moons: Europa, Io, Ganymede and Callisto. The signatures of the other moons were previously spotted in Jupiter’s atmosphere, but this new research represented the first time that Callisto’s effect was found.

Callisto and the other Galilean moons may have formed with the assistance of Saturn. A computer model released in 2018 suggested that as Saturn’s core grew, its gravitational influence moved planetesimals (baby planets) toward the inner solar system. This process might have provided enough stuff to form the four Galilean moons.

Outstanding questions

If Callisto is habitable — and how it formed that way — are among the outstanding questions that the JUICE mission will start studying. JUICE is slated to launch toward Jupiter in 2022 and work at the planet for at least three years, between 2030 and 2033.

JUICE will focus on the moon Ganymede, but its science objectives for Callisto will be similar. This includes looking for ocean layers or water reservoirs, mapping the surface, looking at the atmosphere and figuring out what Callisto’s interior looks like.

Recent scientific papers include modeling how Callisto’s and Jupiter’s magnetic fields interact (the study provided more evidence for a subsurface ocean on Callisto) and finding atomic oxygen in the atmosphere using the Hubble Space Telescope. Other papers have focused on aspects such as the possible water under its surface, refining the crater counts on its surface, and atmospheric investigations.

Additional resource

If Planet 9 is out There, Here’s Where to Look

#Planet9 #space #astronomy #pluto #solarsystem #Pluto #neptune

There are eight known planets in the solar system (ever since Pluto was booted from the club), but for a while, there has been some evidence that there might be one more. A hypothetical Planet 9 lurking on the outer edge of our solar system. So far this world has eluded discovery, but a new study has pinned down where it should be.

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The evidence for Planet 9 comes from its gravitational pull on other bodies. If the planet exists, its gravity will affect the orbits of other planets. So if something seems to be tugging on a planet, just do a bit of math to find the source. This is how Neptune was discovered, when John Couch Adams and Urbain Le Verrier noticed independently that Uranus seemed to be tugged by an unseen planet.

In the case of Planet 9, we don’t have any gravitational effect on a planet. What we do see is an odd clustering of small icy bodies in the outer solar system known as Kuiper belt objects (KBOs). If there were no planet beyond the Kuiper belt, you would expect the orbits of KBOs to be randomly oriented within the orbital plane of the solar system. But instead, we see lots of KBO orbits are clustered in the same orientation. It’s possible that this is just due to random chance, but that isn’t likely.

The possible orbit of Planet Nine. Credit: CalTech/R. Hurt (IPAC)

Back in 2016, the authors looked at the statistical distribution of KBOs and concluded the clustering was caused by an undetected outer planet. Based on their calculations, this world has a mass of 5 Earths and is about 10 times more distant from the Sun than Neptune. The paper even calculated a broad region of the sky where the planet might be. But searches turned up nothing. This led some to conclude the planet doesn’t exist. Orbital oddness doesn’t prove a planet exists. Just ask Planet Vulcan. Others went so far as to argue Planet 9 does exist, but we can’t see it because it’s a primordial black hole.

This new study reexamines the original work in light of some of the criticism it received. One big criticism is that outer solar system bodies are difficult to find, so we look for them where it’s convenient. The clustering effect we see could just be due to biased data. Taking observational bias into effect, the authors find the clustering is still statistically unusual. There’s only a 0.4% chance of it being a fluke. When they recalculated the likely orbit of Planet 9, they were able to better localize where to look.

One interesting aspect of the study is that the newly calculated orbit puts Planet 9 closer to the Sun than originally thought. This is odd, because if it is closer then we should have already found it. The authors argue that observations thus far have ruled out the closest options for Planet 9, which helps narrow down its possible location even further. If the planet exists, it should be detectable by the Vera Rubin Observatory in the near future.

This study isn’t conclusive, and many astronomers still argue that Planet 9 doesn’t exist. But this study makes it clear that we won’t have to argue about it for much longer. Either it will be discovered soon, or observations will rule it out as an explanation for the KBO clustering effect.

Mysterious ‘Planet Nine’ Is Probably 5 to 10 Times the Size of Earth

There could be a planet hiding out on the distant frontiers of our solar system. And astronomers have published new details about what it probably looks like, if it really exists.

Planet 9, according to a new paper published online Feb. 10 in the journal Physics Reports, is probably five to 10 times the mass of Earth. And it probably travels along an elongated orbit that peaks at 400 times Earth’s distance from the sun. That orbit is also likely 15 to 25 degrees off the main orbital plain of our solar system where most planets orbit.

The existence of Planet Nine, as Live Science sister site Space.com previously reported, is an idea that’s become popular among astronomers ever since it was first seriously proposed back in 2014. Researchers suspect the planet’s existence because of patterns of objects in the Kuiper Belt, a ring of debris in the outer solar system. Those objects tend to clump together in ways that suggest that gravity from something big out there is tugging on them.

And the evidence has only gotten stronger. In a separate paper, published Jan. 22 in The Astronomical Journal, some of the same authors of the Physics Report paper calculated the probability of Planet Nine not existing at just 1 in 500. [Amazing Astronomy: Victorian-Era Illustrations of the Heavens]

Strongly suspecting that the dark planet exists isn’t the same thing as knowing it’s real, though. The good news is that this new research suggests that Planet Nine is significantly nearer-by than previously thought. But astronomers still have a lot of space in which to search for it.

The authors of the Physics Reports paper did raise, however, the possibility that there’s no planet out there at all. They added that however strong the current evidence is, that chance should be “taken seriously.”

The likeliest alternative explanation is that humanity’s picture of the Kuiper Belt is incomplete and that the objects only appear to cluster because of some bias in efforts to detect them. It’s also possible, the authors suggested, that the clustering results from the “self-gravity” of the Kuiper Belt acting on its own objects and does not arise from not some hidden planet’s tug.

Still, astronomers have become more convinced by the evidence for Planet Nine in recent years. And now they’re making significant progress toward pinpointing it out in space.

A bad solar storm could cause an “Internet apocalypse”

#solarstorm #Internet #apocalypse #cme #sun #solarflare

Undersea cables would be hit especially hard by a coronal mass ejection.

A man walks alongside a cable that runs across a damp, desolate field.
Enlarge / Even if the power comes back after the next big solar storm, the Internet may not.Jean Claude Moschetti | REA | REDUX
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Scientists have known for decades that an extreme solar storm, or coronal mass ejection, could damage electrical grids and potentially cause prolonged blackouts. The repercussions would be felt everywhere from global supply chains and transportation to Internet and GPS access. Less examined until now, though, is the impact such a solar emission could have on Internet infrastructure specifically. New research shows that the failures could be catastrophic, particularly for the undersea cables that underpin the global Internet.

At the SIGCOMM 2021 data communication conference on Thursday, Sangeetha Abdu Jyothi of the University of California, Irvine presented “Solar Superstorms: Planning for an Internet Apocalypse,” an examination of the damage a fast-moving cloud of magnetized solar particles could cause the global Internet. Abdu Jyothi’s research points out an additional nuance to a blackout-causing solar storm: the scenario where even if power returns in hours or days, mass Internet outages persist.

There’s some good news upfront. Abdu Jyothi found that local and regional Internet infrastructure would be at low risk of damage even in a massive solar storm, because optical fiber itself isn’t affected by geomagnetically induced currents. Short cable spans are also grounded very regularly. But for long undersea cables that connect continents, the risks are much greater. A solar storm that disrupted a number of these cables around the world could cause a massive loss of connectivity by cutting countries off at the source, even while leaving local infrastructure intact. It would be like cutting flow to an apartment building because of a water main break.

“What really got me thinking about this is that with the pandemic we saw how unprepared the world was. There was no protocol to deal with it effectively and it’s the same with Internet resilience,” Abdu Jyothi told WIRED ahead of her talk. “Our infrastructure is not prepared for a large-scale solar event. We have very limited understanding of what the extent of the damage would be.”Advertisement

That information gap mostly comes from lack of data. Severe solar storms are so rare that there are only three main examples to go off of in recent history. Large events in 1859 and 1921 demonstrated that geomagnetic disturbances can disrupt electrical infrastructure and communication lines like telegraph wires. During the massive 1859 “Carrington Event,” compass needles swung wildly and unpredictably, and the aurora borealis was visible at the equator in Colombia. But those geomagnetic disturbances occurred before modern electric grids were established. A moderate-severity solar storm in 1989 knocked out Hydro-Québec’s grid and caused a nine-hour blackout in northeast Canada, but that too occurred before the rise of modern Internet infrastructure.

Though they don’t happen often, coronal mass ejections are a real threat to Internet resilience, says Abdu Jyothi. And after three decades of low solar storm activity, she and other researchers point out that the probability of another incident is rising.

Undersea Internet cables are potentially susceptible to solar storm damage for a few reasons. To shepherd data across oceans intact, cables are fitted with repeaters at intervals of roughly 50 to 150 kilometers depending on the cable. These devices amplify the optical signal, making sure that nothing gets lost in transit, like a relay throw in baseball. While fiber optic cable isn’t directly vulnerable to disruption by geomagnetically induced currents, the electronic internals of repeaters are—and enough repeater failures will render an entire undersea cable inoperable. Additionally, undersea cables are only grounded at extended intervals hundreds or thousands of kilometers apart, which leaves vulnerable components like repeaters more exposed to geomagnetically induced currents. The composition of the sea floor also varies, possibly making some grounding points more effective than others.

On top of all of this, a major solar storm could also knock out any equipment that orbits the Earth that enables services like satellite Internet and global positioning.

“There are no models currently available of how this could play out,” Abdu Jyothi says. “We have more understanding of how these storms would impact power systems, but that’s all on land. In the ocean it’s even more difficult to predict.”

Coronal mass ejections tend to have more impact at higher latitudes, closer to the Earth’s magnetic poles. That’s why Abdu Jyothi worries more about cables in some regions than others. She found, for example, that Asia faces less risk, because Singapore acts as a hub for many undersea cables in the region and is at the equator. Many cables in that region are also shorter, because they branch in many directions from that hub rather than being set up as one continuous span. Cables that cross the Atlantic and Pacific oceans at high latitude would be at greater risk from even moderate storms.

The global Internet is built for resilience. If one pathway isn’t available, traffic reroutes across other paths, a property that could potentially keep connectivity up, even at reduced speeds, in the event of a solar storm. But enough damage to these vital arteries would start to destabilize the network. And depending on where the cable outages occur, Abdu Jyothi says that foundational data routing systems like the Border Gateway Protocol and Domain Name System could start to malfunction, creating knock-on outages. It’s the Internet version of the traffic jams that would happen if road signs disappeared and traffic lights went out at busy intersections across a major city.

North America and some other regions have minimum standards and procedures for grid operators related to solar storm preparedness. And Thomas Overbye, director of the Smart Grid Center at Texas A&M University, says that grid operators have made some progress mitigating the risk over the past 10 years. But he emphasizes that since geomagnetic disturbances are so rare and relatively unstudied, other threats from things like extreme weather events or cyberattacks are increasingly taking priority.

“Part of the problem is we just don’t have a lot of experience with the storms,” Overbye says. “There are some people who think a geomagnetic disturbance would be a catastrophic scenario and there are others who think it would be less of a major event. I’m kind of in the middle. I think it’s something that we certainly as an industry want to be prepared for and I’ve been working to develop tools that assess risk. But yet there are a lot of other things going on in the industry that are important, too.”

The Internet infrastructure side contains even more unknowns. Abdu Jyothi emphasizes that her study is just the beginning of much more extensive interdisciplinary research and modeling that needs to be done to fully understand the scale of the threat. While severe solar storms are extremely rare, the stakes are perilously high. A prolonged global connectivity outage of that scale would impact nearly every industry and person on Earth.

The Dalnegorsk UFO Crash: Roswell Incident of the Soviet Union

#Dalnegorsk #UFO #Crash #Roswell #SovietUnion

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This internationally famous UFO incident took place in 1986, on January 29, at 7:55 p.m. Some have called it the Roswell Incident of the Soviet Union. The information concerning this incident was sent to us by a number of Russian ufologists.The Dalnegorsk UFO Crash: Roswell Incident of the Soviet UnionThe Dalnegorsk UFO Crash: Roswell Incident of the Soviet Union

Dalnegorsk is a small mining town in the Far East of Russia. That cold January day a reddish sphere flew into this town from the southeastern direction, crossed part of Dalnegorsk, and crashed at the Izvestkovaya Mountain (also known as Height or Hill 611, because of its size). The object flew noiselessly, and parallel to the ground; it was approximately three meters in diameter, of a near-perfect round shape, with no projections or cavities, its colour similar to that of burning stainless steel. One eyewitness, V. Kandakov, said that the speed of the UFO was close to 15 meters per hour. The object slowly ascended and descended, and its glow would heat up every time it rose up. On its approach to Hill 611 the object “jerked”, and fell down like a rock.

All witnesses reported that the object “jerked” or “jumped”. Most of them recall two “jumps”. Two girls remember that the object actually “jumped” four times. The witnesses heard a weak, muted thump. It burned intensively at the cliff’s edge for an hour. A geological expedition to the site, led by V. Skavinsky of the Institute of Geology and Geophysics of the Siberian Branch of the Soviet Academy of Sciences (1988), had confirmed the object’s movements through a series of chemical and physical tests of the rocks collected from the site. Valeri Dvuzhilni, head of the Far Eastern Committee for Anomalous Phenomena, was the first to investigate the crash. With the help of our colleagues in Russia this is the most accurate account of the incident to date.

Dr. Dvuzhilni arrived at the site two days after the crash. Deep snow was covered the area at the time. The site of the crash, located on a rocky ledge, was devoid of snow. All around the site remnants of silica splintered rocks were found: (due to exposure to high temperatures), and “smoky” looking. Many pieces, and a nearby rock, contained particles of silvery metal, some “sprayed”-like, some in the form of solidified balls. At the edge of the site a tree-stump was found. It was burnt and emitted a chemical smell. The objects collected at the site were later dubbed as “tiny nets”, “little balls”, “lead balls”, “and glass pieces” (that is what each resembled).

Closer examination revealed very unusual properties. One of the “tiny nets” contained torn and very thin (17 micrometers) threads. Each of the threads consisted of even thinner fibers, tied up in plaits. Intertwined with the fibers were very thin gold wires. Soviet scientists, at such facilities as the Omsk branch of the Academy of Sciences, analyzed all collected pieces. Without going into specific details suffice it to say that the technology to produce such materials was not yet available on Earth…except for one disturbing account.

To give an idea of the complexity of the composition of the pieces, let us look at the “iron balls”. Each of them had its own chemical composition: iron, and a large mixture of aluminum, manganese, nickel, chromium, tungsten, and cobalt.

Such differences indicate that the object was not just a piece of lead and iron, but some heterogeneous construction made from heterogeneous alloys with definite significance. When melted in a vacuum, some pieces would spread over a base, while at another base they would form into balls. Half of the balls were covered with convex glass-like structures. Neither the physicists nor physical metallurgists can say what these structures are, what their composition is. The “tiny nets” (or “mesh”) have confused many researchers. It is impossible to understand their structure and nature of the formation.

A. Kulikov, an expert on carbon at the Chemistry Institute of the Far Eastern Department of the Academy of Sciences, USSR, wrote that it was not possible to get an idea what the “mesh” is. It resembles glass carbon, but conditions leading to such formation are unknown. Definitely a common fire could not produce such glass carbon. The most mysterious aspect of the collected items was the disappearance, after vacuum melting, of gold, silver, and nickel, and the appearance-from nowhere-of molybdenum, that was not in the chamber to begin with.

The only thing that could be more or less easily explained was the ash found on site. Something biological was burned during the crash. A flock of birds, perhaps, or a stray dog; or someone who was inside the crashed object?

Dr. Dvuzhilni’s article was published in a Soviet (Uzbekistan) Magazine NLO: Chto, Gde, Kogda? (Issue 1, 1990, reprint of an article in FENOMEN Magazine, March 23, 1990). In his article Dalnegorski Phenomen V. Dvuzhilni provides details unavailable elsewhere.

The southwesterly trajectory of the object just about coincides with the Xichang Cosmodrome of People’s Republic of China, where satellites are launched into geo synchronous orbit with the help of the Great March-2 carrier rockets. There is no data of any rocket launches in the PRC at the end of January. At the same time, Sinxua Agency reported on January 25, 1988, that there was a sighting of a glowing red sphere not far from the Cosmodrome, where it hovered for 30 minutes. Possibly, UFOs had shown interest toward the Chinese Cosmodrome in the years 1989 and 1988.

There is another curious detail: at the site of the Height 611 small pieces of light gray color were discovered, but only in the area of the contact. These specimens did not match any of the local varieties of soil. What is amazing, the spectroscopic analysis of the specimens matched them to the Yaroslavl tuffs of the polymetalic deposits (i.e. the specimens possessed some characteristic elements of the Yaroslavl, but not the Dalnegorsk, tuffs). There is a possibility that the object obtain pieces of tuff in the Yaroslavl area. Tuffs experience metamorphosis under the effect of high temperatures .

The site of the crash itself was something like an anomalous zone. It was “active” for three years after the crash. Insects avoid the place. The zone affects mechanical and electronic equipment. Some people, including a local chemist, actually got very sick.

This Hill 611 is located in the area of numerous anomalies; according to an article in the Soviet digest Tainy XX Veka (Moscow, 1990, CP Vsya Moskva Publishing House). Even photos taken at the site, when developed, failed to show the hill, but did clearly show other locations. Members of an expedition to the site reported later that their flashlights stopped working at the same time. They checked the flashlights upon returning home, and discovered burned wires.

Eight days after the UFO crash at Hill 611, on February 8, 1986, at 8:30 p.m., two more yellowish spheres flew from the north, in the southward direction. Reaching the site of the crash, they circled it four times, then turned back to the north and flew away. Then on November 28, 1987 (Saturday night, 11:24 p.m.), 32 flying objects had appeared from nowhere. There were hundreds of witnesses, including the military and civilians.

The objects flew over 12 different settlements, and 13 of them flew to Dalnegorsk and the site. Three of the UFOs hovered over the settlement, and five of them illuminated the nearby mountain. The objects moved noiselessly, at an altitude between 150 to 800 meters. None of the eyewitnesses actually thoughts they were UFOs. Those who observed the objects assumed they were aircraft involved in some disaster, or falling meteorites. As the objects flew over houses, they created interference (television, telegraph functions).

The Ministry of Internal Affairs officers, who were present, testified later that they observed the objects from a street, at 23:30 (precise time). They saw a fiery object, flying in from the direction of Gorely settlement. In front of the fiery “flame” was a lusterless sphere, and in the middle of the object was a red sphere. Another group of eyewitnesses included workers from the Bor quarry. They observed an object at 11:00 pm. A giant cylindrical object was flying straight at the quarry. Its size was like that of a five-story building, its length around 200 or 300 hundred meters. The front part of the object was lit up, like a burning metal. The workers were afraid that the object would crash on them. One of the managers of the quarry observed an object at 11:30 pm.

The object was slowly moving at an altitude of 300 meters. It was huge, and cigar-shaped. The manager, whose last name was Levakov, stated that he was well acquainted with aerodynamics, knew theory and practice of flight, but never knew that a body could fly noiselessly without any wings or engines. Another eyewitness, a kindergarten teacher, saw something else. It was a bright, blinding sphere at an altitude of a nine-story building. It moved noiselessly. In front of the sphere Ms. Markina observed a dark, metallic-looking elongated object of about 10 to 12 meters long. It hovered over a school. There the object emitted a ray (its diameter about half a meter). The colour of the ray was violet-bluish. The ground below illuminated, but there were no shadows from objects below. Then the object in the sky approached a mountain and hovered over it. It illuminated the mountain, emitted a reddish projector-like light, as if searching for something, and then departed, flying over the mountain.

No rocket launches took place at any of the Soviet cosmodromes either on January 29, 1986, or November 28, 1987.

Dr. Dvuzhilni’s conclusion is that it was a malfunctioning alien space probe that crashed into the Hill 611. Another hypothesis has it that the object managed to ascend, and escape (almost in one piece) in the north-easterly direction and probably crashed in the dense taiga.

To be continued
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What’s Going on With Russia’s Space Program?

#Russia #Space #Program #ISS #Nauka

Was the recent ISS emergency an aberration, or a warning of things to come?

An inauspicious start: The newly arrived Nauka science module (right) alongside a Soyuz crew vehicle. (Roskosmos)

Last month, something that long-time observers of the space program thought might never happen actually took place 450 kilometers above Earth: Russia’s 20-ton Nauka (“Science”) module successfully docked to the International Space Station. It was the first expansion of the Russian segment of the station in more than a decade. All the other ISS partners largely completed construction of their facilities years ago.

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As its name suggests, Nauka is designed as a laboratory, complete with a workshop, a glovebox for experiments, attachment points for exterior payloads, an airlock, and a European-built robotic arm that will allow cosmonauts to install equipment outside the station—the first such capability on the Russian segment. Nauka also adds more sleeping space for the cosmonauts and a new toilet hooked up to a sophisticated water-recycling system.

The new module launched to the station on a Proton-M rocket on July 21. After eight days of mostly silence from the Russian space agency Roskosmos about Nauka’s trouble-laden trek to its destination and nerve-racking final approach to the ISS the successful docking was met with fanfare in Moscow. “Starting today, foreigners are learning to pronounce a new Russian word—Nauka,” declared Roskosmos head Dmitry Rogozin. Meanwhile, on Russian social media an army of online trolls went into overdrive to trumpet the success.

Just three hours later, though, the mood turned dramatically. People monitoring communications from the station heard alarming reports from the cosmonauts reporting that Nauka’s thrusters were firing for no reason, sending the entire station into an uncontrolled cartwheel. Live broadcasts from orbit showed a blizzard of flakes outside the station—apparent engine exhaust. There were some tense moments on the ground as other station modules had to be fired to counter the unexpected thrust and bring the station back under control. The emergency ended only when Nauka ran out of fuel.

The inadvertent engine firings, which could have damaged the $100 billion ISS, were the result of a software error. Another programming mistake days earlier had also caused propulsion problems, wasting fuel and leaving mission controllers only one attempt at docking.

As usual, Roskosmos has been mostly silent about the mishaps, leaving it largely to independent researchers to sort out what actually happened. Coincidently, the Russian Duma is now preparing a law that would criminalize virtually any reporting on Russian space and military activities.

What has happened to Russia’s once elite human spaceflight program?

Nauka’s journey, like other events in the international spotlight, even the Olympics, are now treated in Russia as part of a propaganda war with the West. Every Kremlin success, no matter how small, is overhyped. Any hint of corruption or mismanagement is glossed over or hidden from view. Often, blame is shifted to the United States or elsewhere. In a post-docking interview that aired on a Russian TV show known for its ultra-nationalist rhetoric, Rogozin blamed Ukrainian-built bellows in Nauka’s propellant tanks for the module’s propulsion problems.

In truth, Nauka’s dangerous post-docking failure was only the latest snafu in a long string of embarrassing technical problems that have plagued the project over three decades. The pervasive software issues were only part of a drama that included changing contractors and major redesigns of Soviet-era systems whose warranties expired years before they had a chance to fly.

Nauka is the last Russian spacecraft that can trace its roots to a transport ship known as TKS, which was developed in the 1960s and ’70s by the collective of the prolific Soviet space pioneer Vladimir Chelomei. The TKS was originally intended for the top-secret Soviet military space station called Almaz. The same design was later used for the modules of the Mir space station, and was then adopted for the first Russian piece of the ISS.

In the 1990s, as the components of the international station were being built around the world, the hardware that eventually became Nauka was planned for launch before the end of that decade. But various financial and technical problems kept it and the rest of the Russian segment on the ground for nearly a quarter of a century.

In the early 2010s, engineers found severe contamination in the module’s critical propulsion system, reportedly the result of workers mistakenly thinking they were supposed to dismantle it. All attempts to fully clear the system failed, but after years of delays, Nauka’s engines were certified to fly anyway. In the final days before launch, Nauka had to be taken off the fueling facility because press photos of the module posted on the Internet revealed the lack of thermal blankets on critical flight control sensors. The blankets had to be urgently fashioned from leftover materials.

What’s next for the troubled science module?

Nauka arrives at an awkward time, as the ISS is approaching an uncertain retirement date. With the Kremlin’s long-proclaimed lunar exploration program stalled by money problems, Russian officials have switched to talking about building a new station in a different orbit from the ISS, although no new money has been allocated to the project so far. This proposed smaller facility would be visited only occasionally by cosmonauts, and could overfly the strategically important Arctic region if multiple technical issues associated with the new orbit can be resolved. In the new orbit, the future Russian station could be reached by crew vehicles and cargo ships spacecraft launched from Russia, rather than from Kazakhstan, as with vehicles bound for the ISS.

Under these circumstances, adding more Russian modules to the current station would seem to make no sense. Yet Roskosmos has kept the next module, called Prichal (“Pier”), on schedule for a launch to the ISS this November. Beyond that, another major component is currently under construction in Russia. This upgraded new-generation version of Nauka, known as the Science and Power Module or NEM, was intended to make the Russian segment truly independent from the rest of the ISS in terms of energy supplies and flight control.

However, this year, Roskosmos publicly committed to making the NEM the core of the new station rather than send it to the ISS. After a closed-door meeting on July 26, the Council of Chief Designers—which has charted the direction of Russia’s space program since the days of Sputnik—deferred all critical questions about the post-ISS base to some unspecified future.

That means Nauka and Prichal may have a relatively short life in orbit compared to their predecessors. And flight controllers on both sides of the world will be left hoping there are no more in-space emergencies like the one that happened last month.

How Far Can SpaceX Starships Go?

#space #spacex #starship #range #astronomy

How far can we go in a SpaceX Starship?? Let’s take a look at what the Starship can actually do, when it comes to humans exploring our solar system.

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Elon musk wants to send starships to Mars obviously, but what about missions to Jupiter, or Saturn, or even beyond that? The answer can be found in the rocket science, and the first thing you need to know is that the SpaceX Starship is heavy. Just by itself, completely empty, it’s 120 tons. Now that’s already the weight of about 40 cars stacked on top of eachother, and we call that the Starship’s dry mass.

But 120 tons gets more than doubled, if the payload bay is filled with 150 tons of… well, you know payload – whatever’s paying for a given mission. Let’s say we’re trying to send 5 people to Jupiter and back. Let’s just quickly, and for example, allocate 150 tons of payload for them, including their own body weight. You got 10 tons of oxygen, 20 tons of water, 10 tons of food, and so on. You get the point.

So now we have 270 tons total, but the starship is on the launch pad with its propellant tanks empty. To fill all the tanks, we need to add a whopping 1230 tons of liquid methane and liquid oxygen, giving us a starting weight of 1500 tons. And that’s just for the Starship, we’ll talk about the booster another time which gets even more propellant than that, filled up inside of it.

Once the booster lifts the starship through the thickest parts of our atmosphere, and gives it a big push on its way to orbit, the Starship will spend almost all of its propellant to get to orbital speed, which is 7.8 kilometers per second, now this is a velocity that is required by any spacecraft that aims to not only get to space, but also remain in space and not fall back down, like the suborbital rockets that are now bringing billionaires into a weightless euphoria.

But the Starship doesn’t use every last drop of propellant getting to orbit. For a normal starship mission with the parameters stated above, once in orbit, there will be just enough propellant left over in the main tanks to perform a deorbit burn, and then there are the special and separate header tanks that hold 30 tons of propellant, reserved only for the propulsive landing, because remember, bringing starships back safely and reusing them is a big part of what makes the SpaceX Starship such a game changer in the world of spaceflight and space exploration.

So how exactly are we supposed to explore the solar system, if our starship is effectively running on empty and is still in low earth orbit?

Well that’s where refilling comes into play.

Record Breaking Asteroid Super Close to the Sun Found – 2021 PH27

#asteroid #2021PH27 #space #astronomy

Astronomers Discover Fastest-Orbiting Asteroid Ever Seen

The newly-discovered asteroid 2021 PH27 has a diameter of about 1 km (3,280 feet) and orbits the Sun in just 113 days — the shortest known orbital period for an asteroid and second shortest for any object in our Solar System after Mercury.

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The asteroid 2021 PH27 was imaged inside Mercury’s orbit and has been colored red and blue to show the two different times where it was imaged on August 13, 2021 — just three minutes apart. Image credit: CTIO / NOIRLab / NSF / DOE / DECam / AURA / S.S. Sheppard, Carnegie Institution of Science.

2021 PH27 has a semi-major axis of 70 million km (43 million miles, 0.46 AU), giving it a 113-day orbital period on an unstable elongated orbit that crosses the orbits of both Mercury and Venus.

This means that within a few million years it will likely be destroyed in a collision with one of these planets or the Sun, or it will be ejected from its current position.

2021 PH27 was discovered by Carnegie Institution for Science’s Dr. Scott Sheppard in images taken by Brown University astronomers Ian Dell’Antonio and Shenming Fu on August 13, 2021.

“Most likely 2021 PH27 was dislodged from the main asteroid belt between Jupiter and Mars and the gravity of the inner planets shaped its orbit into its current configuration,” Dr. Sheppard said.

“Although, based on its large angle of inclination of 32 degrees, it is possible that 2021 PH27 is an extinct comet from the outer Solar System that ventured too close to one of the planets as the path of its voyage brought it into proximity with the inner Solar System.”

An illustration of 2021 PH27’s orbit. Image credit: CTIO / NOIRLab / NSF / AURA / J. da Silva, Spaceengine.org.

Because 2021 PH27 is so close to the Sun’s massive gravitational field, it experiences the largest general relativistic effects of any known solar system object.

This is seen in a slight angular deviation in its elliptical orbit over time, a movement called precession, which occurs at about one arcminute per century.

Observation of Mercury’s precession puzzled scientists until Albert Einstein’s theory of general relativity explained its orbital adjustments over time. The precession of 2021 PH27 is even faster than Mercury’s.

“2021 PH27 gets so close to the Sun that its surface temperature gets to 482 degrees Celsius (900 degrees Fahrenheit) at closest approach, hot enough to melt lead,” Dr. Sheppard said.

The asteroid will soon pass behind the Sun and be unobservable from Earth until early next year, at which time observers will be able to refine its orbit to the precision needed to give it an official name.

The discovery of 2021 PH27 is reported in the Minor Planet Electronic Circular.

Astronomer reveals never-before-seen detail of the center of our galaxy

#Astronomer #astronomy #space #galaxy #center #chandra #milkyway #interstellarengery

New image made using NASA’s Chandra X-Ray Observatory hints at previously unknown interstellar energy source at the Milky Way center

New research reveals, with unprecedented clarity, details of violent phenomena in the center of our galaxy.

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New research by University of Massachusetts Amherst astronomer Daniel Wang reveals, with unprecedented clarity, details of violent phenomena in the center of our galaxy. The images, published recently in Monthly Notices of the Royal Astronomical Society, document an X-ray thread, G0.17-0.41, which hints at a previously unknown interstellar mechanism that may govern the energy flow and potentially the evolution of the Milky Way.

“The galaxy is like an ecosystem,” says Wang, a professor in UMass Amherst’s astronomy department, whose findings are a result of more than two decades of research. “We know the centers of galaxies are where the action is and play an enormous role in their evolution.” And yet, whatever has happened in the center of our own galaxy is hard to study, despite its relative proximity to Earth, because, as Wang explains, it is obscured by a dense fog of gas and dust. Researchers simply can’t see the center, even with an instrument as powerful as the famous Hubble Space Telescope. Wang, however, has used a different telescope, NASA’s Chandra X-Ray Observatory, which “sees” X-rays, rather than the rays of visible light that we perceive with our own eyes. These X-rays are capable of penetrating the obscuring fog — and the results are stunning.

Wang’s findings, which were supported by NASA, give the clearest picture yet of a pair of X-ray-emitting plumes that are emerging from the region near the massive black hole lying at the center of our galaxy. Even more intriguing is the discovery of an X-ray thread called G0.17-0.41, located near the southern plume. “This thread reveals a new phenomenon,” says Wang. “This is evidence of an ongoing magnetic field reconnection event.” The thread, writes Wang, probably represents “only the tip of the reconnection iceberg.”

A magnetic field reconnection event is what happens when two opposing magnetic fields are forced together and combine with one another, releasing an enormous amount of energy. “It’s a violent process,” says Wang, and is known to be responsible for such well-known phenomena as solar flares, which produce space weather powerful enough to disrupt power grids and communications systems here on Earth. They also produce the spectacular Northern Lights. Scientists now think that magnetic reconnection also occurs in interstellar space and tends to take place at the outer boundaries of the expanding plumes driven out of our galaxy’s center.

“What is the total amount of energy outflow at the center of the galaxy? How is it produced and transported? And how does it regulate the galactic ecosystem?” These, says Wang, are the fundamental questions whose answers will help to unlock the history of our galaxy. Though much work remains to be done, Wang’s new map points the way. For more information, including additional images and video, visit the Chandra X-Ray Observatory’s Galactic Center website.

Chandra Survey of Galactic Center
A panorama of the Galactic Center builds on previous surveys from Chandra and other telescopes. This latest version expands Chandra’s high-energy view farther above and below the plane of the galaxy – that is, the disk where most of the galaxy’s stars reside – than previous imaging campaigns. In the first two images, X-rays from Chandra are orange, green, and purple, showing different X-ray energies, and the radio data from MeerKAT are gray. Credit: X-ray: NASA/CXC/UMass/Q.D. Wang; Radio: NRF/SARAO/MeerKAT

New research by University of Massachusetts Amherst astronomer Daniel Wang reveals, with unprecedented clarity, details of violent phenomena in the center of our galaxy. The images, published recently in Monthly Notices of the Royal Astronomical Society, document an X-ray thread, G0.17-0.41, which hints at a previously unknown interstellar mechanism that may govern the energy flow and potentially the evolution of the Milky Way.
“The galaxy is like an ecosystem,” says Wang, a professor in UMass Amherst’s astronomy department, whose findings are a result of more than two decades of research. “We know the centers of galaxies are where the action is and play an enormous role in their evolution.” And yet, whatever has happened in the center of our own galaxy is hard to study, despite its relative proximity to Earth, because, as Wang explains, it is obscured by a dense fog of gas and dust. Researchers simply can’t see the center, even with an instrument as powerful as the famous Hubble Space Telescope. Wang, however, has used a different telescope, NASA’s Chandra X-Ray Observatory, which “sees” X-rays, rather than the rays of visible light that we perceive with our own eyes. These X-rays are capable of penetrating the obscuring fog — and the results are stunning.

Chandra Survey of Galactic Center Labeled
This version of the image highlights several key features of this new Galactic Center survey. The threads are labeled with red rectangles in the image, while X-rays reflected from dust around bright X-ray sources (green circles), Sagittarius A*. In purple circles and ellipses, the Arches and Quintuplet Clusters, DB00-58 and DB00-6, 1E 1743.1-28.43, the Cold Gas Cloud and Sagittarius C are outlined. Credit: X-ray: NASA/CXC/UMass/Q.D. Wang; Radio: NRF/SARAO/MeerKAT

Wang’s findings, which were supported by NASA, give the clearest picture yet of a pair of X-ray-emitting plumes that are emerging from the region near the massive black hole lying at the center of our galaxy. Even more intriguing is the discovery of an X-ray thread called G0.17-0.41, located near the southern plume. “This thread reveals a new phenomenon,” says Wang. “This is evidence of an ongoing magnetic field reconnection event.” The thread, writes Wang, probably represents “only the tip of the reconnection iceberg.”

A magnetic field reconnection event is what happens when two opposing magnetic fields are forced together and combine with one another, releasing an enormous amount of energy. “It’s a violent process,” says Wang, and is known to be responsible for such well-known phenomena as solar flares, which produce space weather powerful enough to disrupt power grids and communications systems here on Earth. They also produce the spectacular Northern Lights. Scientists now think that magnetic reconnection also occurs in interstellar space and tends to take place at the outer boundaries of the expanding plumes driven out of our galaxy’s center.

“What is the total amount of energy outflow at the center of the galaxy? How is it produced and transported? And how does it regulate the galactic ecosystem?” These, says Wang, are the fundamental questions whose answers will help to unlock the history of our galaxy. Though much work remains to be done, Wang’s new map points the way. For more information, including additional images and video, visit the Chandra X-Ray Observatory’s Galactic Center website.

The Best Evidence for Life on Mars Might be Found on its Moons

#space #lifeonmars #mars #moons #astronomy #extraterrestria #ET

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The search for Martian life has been ongoing for decades.  Various landers and rovers have searched for biosignatures or other hints that life existed either currently or in the past on the Red Planet.  But so far, results have been inconclusive.  That might be about to change, though, with a slew of missions planned to collect even more samples for testing.  Mars itself isn’t the only place they are looking, though. Some scientists think the best place to find evidence of life is one of Mars’ moons. 

Phobos and Deimos are usually an afterthought when discussing Mars exploration priorities, but interest has been growing recently due to their unique place in the overall Martian system.  They might serve as a depository for material that was blasted off of Mars’ surface in the past.

tUT video discussing the possibility of life on Mars.

Many scientists think that early Mars could have been habitable, with temperatures in a biologically suitable range, an atmosphere that hadn’t yet been stripped away, and liquid water flowing on its surface, some of which formed Jerezo Crater, where Perseverance is now exploring.  If any life existed back in these more hospitable conditions, it would have been subjected to the catastrophes commonly thought of as extinction-level events here on Earth – asteroid impacts.

Asteroid impacts were much more common earlier in the solar system’s formation, ejecting a multitude of the Martian regolith into space.  While some of that ejecta takes the form of meteorites that eventually wind up on Earth, a large amount of it is absorbed by the moons, particularly Phobos.  Scientists estimate that over 1 billion kg of ejected material was deposited relatively evenly across Phobos’ surface, making up over 1000 parts per million of the material on the small moon. 

UT video discussing how life on Mars and Earth could be related.

The moon itself is incapable of supporting life – it has no water to speak of and is constantly irradiated by the sun and more general cosmic rays.  No life could survive on its surface, yet searching for life on Phobos still has some major advantages over searching for life on Mars itself.

While Mars doesn’t have a traditional weather cycle, like Earth’s, its surface changes regularly, with dust storms and wind causing the erosion and deposition of long-standing geological edifices.  However, both Martian moons lack any such system, so any biosignature that landed there from an asteroid impact would likely still be in the same position now, and in much the same shape it would have been in when it was blasted in space.

https://www.youtube.com/embed/dmtCX-TBgfE?UT video discussing the Mars Sample Return Mission

This is all great in theory, but getting data to prove that theory is another matter entirely.  Luckily there are a series of missions in the works to attempt to do so.  The Mars Sample Return mission (MSR) is ongoing, and Perseverance’s jaunt in Jezero Carter is the first step. The Japanese Space Agency’s Mars Moons eXploration (MMX) mission plans to return to Earth with a regolith sample from Phobos in 2029.

Another advantage that MMX would have over the MSR is that the debris spread across Phobos’ surface wouldn’t be specific to a particular area on Mars, unlike the samples of Jezero that Perseverance is currently attempting to collect. Asteroid impacts are equally destructive ejecta creators, so if life happened to spring up only in a certain region of Mars, it would be more likely to have been caught in an asteroid impact and partially deposited on Phobos. There’s a much better chance of scientists finding that evidence there than of them luckily choosing the right area to look in with no previous knowledge.

UT video on why it might be better to send humans to Mars’ moons first.

No matter where they look, and no matter what they find, scientists working on both the MSR and MMX missions will be adding valuable knowledge to humanity’s stockpile.  And if they happen to find evidence of one of the most important discoveries in history, so much the better.

Dyson Spheres Around Super Massive Black Holes

#DysonSphere #BlackHoles #space #astonomy #physics #aliens #extraterrestrial

An artist’s impression of a Dyson sphere surrounding a star DOTTED YETI/SHUTTERSTOCK

Black holes surrounded by massive, energy-harvesting structures could power alien civilizations!

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In the long-running TV show Doctor Who, aliens known as time lords derived their power from the captured heart of a black hole, which provided energy for their planet and time travel technology. The idea has merit, according to a new study. Researchers have shown that highly advanced alien civilizations could theoretically build megastructures called Dyson spheres around black holes to harness their energy, which can be 100,000 times that of our Sun. The work could even give us a way to detect the existence of these extraterrestrial societies.

“I like these speculations about what advanced civilizations might do,” says Tomáš Opatrný, a physicist at Palacký University Olomouc, who was not involved with the work but agrees that a Dyson sphere around a black hole would provide its builders with lots of power.

If humanity’s energy demands continue to grow, a point will come when our power consumption approaches, or even exceeds, the total energy available to our planet. So argued physicist Freeman Dyson way back in 1960. Borrowing from British sci-fi author Olaf Stapledon, Dyson proposed that any sufficiently advanced civilization that wanted to survive would need to build massive structures around stars that could harness their energy.

Most of these Dyson spheres involve numerous satellites orbiting or sitting motionlessly around a star. (A solid shell totally encasing a solar body—as envisioned in a Star Trek: The Next Generation episode—is considered mechanically impossible, because of the gravity and pressure from the central star.) Such megastructures would have to transform that solar energy into usable energy, a process that creates waste heat. This heat shows up in the midinfrared spectrum, and stars with an excess infrared signal have become a key target in the search for extraterrestrial life.

But astronomer Tiger Hsiao of National Tsing Hua University says we might be looking for the wrong thing. In a new study, he and colleagues set out to calculate whether it would also be possible to use a Dyson sphere around a black hole. They analyzed black holes of three different sizes: those five, 20, and 4 million times the mass of our Sun. These, respectively, reflect the lower and upper limits of black holes known to have formed from the collapse of massive stars—and the even more enormous mass of Sagittarius A*, the supermassive massive black hole thought to lurk at the center of the Milky Way.

Black holes are typically thought of as consumers rather than producers of energy. Yet their huge gravitational fields can generate power through several theoretical processes. These include the radiation emitted from the accumulation of gas around the hole, the spinning “accretion” disk of matter slowly falling toward the event horizon, the relativistic jets of matter and energy that shoot out along the hole’s axis of rotation, and Hawking radiation—a theoretical way that black holes can lose mass, releasing energy in the process.

From their calculations, Hsiao and colleagues concluded that the accretion disk, surrounding gas, and jets of black holes can all serve as viable energy sources. In fact, the energy from the accretion disk alone of a stellar black hole of 20 solar masses could provide the same amount of power as Dyson spheres around 100,000 stars, the team will report next month in the Monthly Notices of the Royal Astronomical Society. Were a supermassive black hole harnessed, the energy it could provide might be 1 million times larger still.

If such technology is at work, there may be a way to spot it. According to the researchers, the waste heat signal from a so-called “hot” Dyson sphere—one somehow capable of surviving temperatures in excess of 3000 kelvin, above the melting point of known metals—around a stellar mass black hole in the Milky Way would be detectible at ultraviolet wavelengths. Such signals might be found in the data from various telescopes, including NASA’s Hubble Space Telescope and Galaxy Evolution Explorer, Hsiao says.

Meanwhile, a “solid” Dyson sphere—operating below 3000 kelvin—could be picked up in the infrared by, for example, the Sloan Digital Sky Survey or the Wide-field Infrared Survey Explorer. The latter is no stranger to looking for the infrared signals of traditional, star-based Dyson spheres. But, like all other such searches, it has yet to find anything conclusive.

Opatrný says using the radiation from accretion disks would be particularly clever, because the disks convert energy more efficiently than the thermonuclear reaction in conventional stars. Aliens concerned with the sustainability of their power supply, he suggests, might be better off encapsulating small stars that burn their fuel slowly. However, he continued, “The fast-living civilizations feeding on black hole accretion disks would be easier to spot from the huge amount of waste heat they produce.”

Inoue Makoto, an astrophysicist from the Academia Sinica Institute of Astronomy and Astrophysics, says regular black holes could support so-called type II civilizations, whose total energy requirements match those of an entire star system. Supermassive black holes, he adds, could fuel type III civilizations, whose power consumption would equal that emitted by an entire galaxy.

As for what the aliens might use this energy for, Opatrný has some thoughts. “Mining cryptocurrency, playing computer games, or just feeding the ever-growing bureaucracy?” he jokingly muses. Either way, maybe the time lords were onto something after all.

Fireball blazes across Texas sky

#Fireball #Texas #sky #astronomy #space

NASA has programs devoted to tracking the exceptionally bright meteors.

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The fire ball that passed over Japan in 2017 is linked to a mile-long asteroid. Scientists now believe that the asteroid, known as 2003 YT1 could break up and harm life on Earth.

Texas residents were stunned to see a fireball blaze across the sky on Sunday night. 

According to NASA Meteor Watch, the celestial spectacle passed overhead just before 9 p.m. CT. 

“Hundreds of eyewitnesses in the states of Texas, Louisiana, Arkansas and Oklahoma report seeing a very bright fireball last night at 8:58 PM Central Daylight Time,” the agency said in a Facebook post on Monday. “Analysis of their reports, combined with information obtained from a couple of videos from public/amateur cameras, shows that the meteor was first seen 48 miles above Texas Highway 11, between Sulphur Springs and Winnsboro. Moving northeast at 30,000 miles per hour, it traveled 59 miles through the upper atmosphere before fragmenting 27 miles above U.S. 82, east of Avery.”

“The fireball was at least as bright as a quarter moon, which translates to something bigger than 6 inches in diameter with a weight of 10 pounds. The slow speed (for a meteor) suggests a small piece of an asteroid produced the fireball,” it added. 

Hundreds uploaded witness reports to the nonprofit American Meteor Society (AMS), including three videos and CBSDFW.com said Monday that others claimed they had heard a “sonic boom.” 

Fireballs are a common occurrence and NASA has programs devoted to tracking the exceptionally bright meteors.

With explosive new result, laser-powered fusion effort nears ‘ignition’

An artist’s rendering shows how the National Ignition Facility’s 192 beams enter an eraser-size cylinder of gold and heat it from the inside to produce x-rays, which then implode the fuel capsule at its center to create fusion. LAWRENCE LIVERMORE NATIONAL LABORATORY
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#laser-powered #fusion #ignition #NIF #physics

More than a decade ago, the world’s most energetic laser started to unleash its blasts on tiny capsules of hydrogen isotopes, with managers promising it would soon demonstrate a route to limitless fusion energy. Now, the National Ignition Facility (NIF) has taken a major leap toward that goal. Last week, a single laser shot sparked a fusion explosion from a peppercorn-size fuel capsule that produced eight times more energy than the facility had ever achieved: 1.35 megajoules (MJ)—roughly the kinetic energy of a car traveling at 160 kilometers per hour. That was also 70% of the energy of the laser pulse that triggered it, making it tantalizingly close to “ignition”: a fusion shot producing an excess of energy.

“After many years at 3% of ignition, this is superexciting,” says Mark Herrmann, head of the fusion program at Lawrence Livermore National Laboratory, which operates NIF.

NIF’s latest shot “proves that a small amount of energy, imploding a small amount of mass, can get fusion. It’s a wonderful result for the field,” says physicist Michael Campbell, director of the Laboratory for Laser Energetics (LLE) at the University of Rochester.

“It’s a remarkable achievement,” adds plasma physicist Steven Rose, co-director of the Centre for Inertial Fusion Studies at Imperial College London. “It’s made me feel very cheerful. … It feels like a breakthrough.”

And it is none too soon, as years of slow progress have raised questions about whether laser-powered fusion has a practical future. Now, according to LLE Chief Scientist Riccardo Betti, researchers need to ask: “What is the maximum fusion yield you can get out of NIF? That’s the real question.”

Fusion, which powers stars, forces small atomic nuclei to meld together into larger ones, releasing large amounts of energy. Extremely hard to achieve on Earth because of the heat and pressure required to join nuclei, fusion continues to attract scientific and commercial interest because it promises copious energy, with little environmental impact.

Yet among the many approaches being investigated, none has yet generated more energy than was needed to cause the reaction in the first place. Large doughnut-shaped reactors called tokamaks, which use magnetic fields to cage a superhot plasma for long enough to heat nuclei to fusion temperatures, have long been the front-runners to achieve a net energy gain. But the giant $25 billion ITER project in France is not expected to get there for more than another decade, although private fusion companies are promising faster progress.

NIF’s approach, known as inertial confinement fusion, uses a giant laser housed in a facility the size of several U.S. football fields to produce 192 beams that are focused on a target in a brief, powerful pulse—1.9 MJ over about 20 nanoseconds. The aim is to get as much of that energy as possible into the target capsule, a diminutive sphere filled with the hydrogen isotopes deuterium and tritium mounted inside a cylinder of gold the size of a pencil eraser. The gold vaporizes, producing a pulse of x-rays that implodes the capsule, driving the fusion fuel into a tiny ball hot and dense enough to ignite fusion. In theory, if such tiny fusion blasts could be triggered at a rate of about 10 per second, a power plant could harvest energy from the high-speed neutrons produced to generate electricity.

When NIF launched, computer models predicted quick success, but fusion shots in the early years only generated about 1 kilojoule (kJ) each. A long effort to better understand the physics of implosions followed and by last year shots were producing 100 kJ. Key improvements included smoothing out microscopic bumps and pits on the fuel capsule surface, reducing the size of the hole in the capsule used to inject fuel, shrinking the holes in the gold cylinder so less energy escapes, and extending the laser pulse to keep driving the fuel inward for longer. The progress was sorely needed, as NIF’s funder, the National Nuclear Security Administration, was reducing shots devoted to ignition in favor of using its lasers for other experiments simulating the workings of nuclear weapons. 

Earlier this year, combining those improvements in various ways, the NIF team produced several shots exceeding 100 kJ, including one of 170 kJ. That result suggested NIF was finally creating a “burning plasma,” in which the fusion reactions themselves provide the heat for more fusion—a runaway reaction that is key to getting higher yields. Then, on 8 August, a shot generated the remarkable 1.35 MJ. “It was a surprise to everyone,” Herrmann says. “This is a whole new regime.”

Exactly which improvements had the greatest impact and what combination will lead to future gains will take a while to unravel, Herrmann says, because several were tweaked at once in the latest shot. “It’s a very nonlinear process. That’s why it’s called ignition: It’s a runaway thing,” he says. But, “This gives us a lot more encouragement that we can go significantly farther.”

Herrmann’s team is a long way from thinking about fusion power plants, however. “Getting fusion in a laboratory is really hard, getting economic fusion power is even harder,” Campbell says. “So, we all have to be patient.” NIF’s main task remains ensuring the United States’s nuclear weapons stockpile is safe and reliable; fusion energy is something of a sideline. But reaching ignition and being able to study and simulate the process will also “open a new window on stewardship,” Herrmann says, because uncontrolled fusion powers nuclear weapons.

Herrmann admits that, when he got a text last week from colleagues saying they’d gotten an “interesting” result from the latest shot, he was worried something might be wrong with the instruments. When that proved not to be the case, “I did open a bottle of champagne.”

Searching for life on Mars and its moons

#life #Mars #moon #space #Extraterrestrial

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The scientific exploration of Mars over the past several decades has resulted in increasing evidence that the martian surface hosted habitable environments early in its history, as well as evidence of the building blocks of life in the form of organic molecules. Habitats on Mars that could harbor extant martian life have been hypothesized, such as subsurface environments, caves, and ice deposits. Mars is currently recognized as a “paleo-habitable” planet, reflecting its ancient habitability. Fully understanding the evolution of habitability and whether Mars has ever hosted life will be essential to understanding and exploring other extraterrestrial habitable environments and potential life-forms. Flagship missions of multiple space agencies in the 2020s will play essential and complementary roles and could finally provide an answer to these long-standing questions.

The planned Mars Sample-Return MSR mission of NASA and the European Space Agency should reveal more about the habitability of Mars by helping to determine the geologic evolution of Jezero crater and its surrounding areas, which are believed to be the site of an ancient lake see the photo. The Mars 2020 Perseverance rover will attempt to collect samples that will allow scientists to explore the evolution of Jezero crater and its habitability over time, as well as samples that may contain evidence of biosignatures. A high-priority science objective for MSR returned-sample science is to understand the habitability of Mars and look for potential signs of both extinct and extant life.

Mars is not alone because it has two small moons, Phobos and Deimos. Throughout the history of Mars, numerous asteroidal impacts on Mars have produced martian impact ejecta, and a fraction of the ejected material has been delivered to its moons. Phobos is closer to Mars, so it has more martian ejecta than Deimos. Numerical simulations show that >109 kg of martian material could be uniformly mixed in the regolith of Phobos the resultant martian fraction is >1000 parts per million.

Even if martian life-forms existed and could survive the transport to Phobos without suffering from impact-shock decomposition with a peak pressure of <5 GPa, the Phobos environment is highly inhospitable. Phobos does not have air or water, and its surface is constantly bathed in solar and galactic cosmic radiation. This indicates that martian materials on Phobos’ surface almost certainly do not contain any living microorganisms.

Embedded Image

Jezero crater on Mars is believed to be the site of an ancient lake. The Mars 2020 Perseverance rover aims to collect samples from the crater to analyze for evidence of life.

Instead, there may be dead biosignatures on Phobos, which we have called “SHIGAI” Sterilized and Harshly Irradiated Genes, and Ancient Imprints—the acronym in Japanese means “dead remains.” SHIGAI includes any potential microorganisms that could have been alive on Mars and were recently sterilized during or after the delivery to Phobos, and the microorganisms and biomarkers that had been processed on ancient Mars before the delivery to Phobos, including potential DNA fragments. The Mars-moon system is an ideal natural laboratory for the study of interplanetary transport and sustainability of SHIGAI on airless bodies in the Solar System.

Should a martian biosphere exist, any biosignatures or biomarkers observed in the samples from Jezero crater could be widespread elsewhere on Mars and possibly occur on the surface of Phobos. Because martian ejecta has been thoroughly delivered to Phobos by impact-driven random sampling, the biosignatures and biomarkers that may be contained in the Phobos regolith could reflect the diversity and evolution of a potential martian biosphere.

Martian Moons eXploration MMX, developed by the Japan Aerospace Exploration Agency, plans to collect a sample of >10 g from the Phobos surface and return to Earth in 2029. Detection of a “fingerprint” of martian life and SHIGAI should be achievable through comprehensive comparative studies using martian material from the Phobos surface and samples from Jezero crater returned by MMX and MSR, respectively.

The MSR samples have the potential to contain a variety of biomarker molecules e.g., lipids, such as hopanoids, sterols, and archaeols, and their diagenetic products. The sample could include modern living organisms from Jezero crater, if they are present. Of course, MSR could return samples without any evidence of life because of the focus on a single location. A distinct advantage for MMX is the ability to deliver martian materials derived from several regions. The random nature of the crater-forming impacts on Mars statistically delivers all possible martian materials, from sedimentary to igneous rocks that cover all of its geological eras.

Mutual international cooperation on MSR and MMX could answer questions such as how martian life, if present, emerged and evolved in time and place. If Mars never had life at all, these missions would then be absolutely vital in unraveling why Mars is lifeless and Earth has life. Therefore, the missions may eventually provide the means to decipher the divergent evolutionary paths of life on Mars and Earth.

Toward next-generation brain-computer interface systems

A new kind of neural interface system that coordinates the activity of hundreds of tiny brain sensors could one day deepen understanding of the brain and lead to new medical therapies

#Brain #BCI #computer #interface #sensor

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Close-up portrait of young and beautiful woman with the virtual futuristic glasses ( technology concept).Virtual holographic interface and young woman wearing glasses

Brain-computer interfaces (BCIs) are emerging assistive devices that may one day help people with brain or spinal injuries to move or communicate. BCI systems depend on implantable sensors that record electrical signals in the brain and use those signals to drive external devices like computers or robotic prosthetics.

Most current BCI systems use one or two sensors to sample up to a few hundred neurons, but neuroscientists are interested in systems that are able to gather data from much larger groups of brain cells.

Now, a team of researchers has taken a key step toward a new concept for a future BCI system — one that employs a coordinated network of independent, wireless microscale neural sensors, each about the size of a grain of salt, to record and stimulate brain activity. The sensors, dubbed “neurograins,” independently record the electrical pulses made by firing neurons and send the signals wirelessly to a central hub, which coordinates and processes the signals.

In a study published on August 12 in Nature Electronics, the research team demonstrated the use of nearly 50 such autonomous neurograins to record neural activity in a rodent.

The results, the researchers say, are a step toward a system that could one day enable the recording of brain signals in unprecedented detail, leading to new insights into how the brain works and new therapies for people with brain or spinal injuries.

“One of the big challenges in the field of brain-computer interfaces is engineering ways of probing as many points in the brain as possible,” said Arto Nurmikko, a professor in Brown’s School of Engineering and the study’s senior author. “Up to now, most BCIs have been monolithic devices — a bit like little beds of needles. Our team’s idea was to break up that monolith into tiny sensors that could be distributed across the cerebral cortex. That’s what we’ve been able to demonstrate here.”

The team, which includes experts from Brown, Baylor University, University of California at San Diego and Qualcomm, began the work of developing the system about four years ago. The challenge was two-fold, said Nurmikko, who is affiliated with Brown’s Carney Institute for Brain Science. The first part required shrinking the complex electronics involved in detecting, amplifying and transmitting neural signals into the tiny silicon neurograin chips. The team first designed and simulated the electronics on a computer, and went through several fabrication iterations to develop operational chips.

The second challenge was developing the body-external communications hub that receives signals from those tiny chips. The device is a thin patch, about the size of a thumb print, that attaches to the scalp outside the skull. It works like a miniature cellular phone tower, employing a network protocol to coordinate the signals from the neurograins, each of which has its own network address. The patch also supplies power wirelessly to the neurograins, which are designed to operate using a minimal amount of electricity.

“This work was a true multidisciplinary challenge,” said Jihun Lee, a postdoctoral researcher at Brown and the study’s lead author. “We had to bring together expertise in electromagnetics, radio frequency communication, circuit design, fabrication and neuroscience to design and operate the neurograin system.”

The goal of this new study was to demonstrate that the system could record neural signals from a living brain — in this case, the brain of a rodent. The team placed 48 neurograins on the animal’s cerebral cortex, the outer layer of the brain, and successfully recorded characteristic neural signals associated with spontaneous brain activity.

The team also tested the devices’ ability to stimulate the brain as well as record from it. Stimulation is done with tiny electrical pulses that can activate neural activity. The stimulation is driven by the same hub that coordinates neural recording and could one day restore brain function lost to illness or injury, researchers hope.

The size of the animal’s brain limited the team to 48 neurograins for this study, but the data suggest that the current configuration of the system could support up to 770. Ultimately, the team envisions scaling up to many thousands of neurograins, which would provide a currently unattainable picture of brain activity.

“It was a challenging endeavor, as the system demands simultaneous wireless power transfer and networking at the mega-bit-per-second rate, and this has to be accomplished under extremely tight silicon area and power constraints,” said Vincent Leung, an associate professor in the Department of Electrical and Computer Engineering at Baylor. “Our team pushed the envelope for distributed neural implants.”

There’s much more work to be done to make that complete system a reality, but researchers said this study represents a key step in that direction.

“Our hope is that we can ultimately develop a system that provides new scientific insights into the brain and new therapies that can help people affected by devastating injuries,” Nurmikko said.

Other co-authors on the research were Ah-Hyoung Lee (Brown), Jiannan Huang (UCSD), Peter Asbeck (UCSD), Patrick P. Mercier (UCSD), Stephen Shellhammer (Qualcomm), Lawrence Larson (Brown) and Farah Laiwalla (Brown). The research was supported by the Defense Advanced Research Projects Agency (N66001-17-C-4013).

Japan tests rotating detonation engine for the first time in space

#Japan #tests #rotating #detonationengine #space #JAXA #Rocketengine

Japan tests rotating detonation engine for the first time in space.
Japan tests rotating detonation engine for the first time in space. Credit: JAXA
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The Japan Aerospace Exploration Agency (JAXA) has announced that it has successfully demonstrated the operation of a “rotating detonation engine” for the first time in space. The novelty of the technologies in question is that such systems obtain a large amount of thrust by using much less fuel compared to conventional rocket engines, which is quite advantageous for space exploration.

On July 27, the Japanese agency launched a pair of futuristic propulsion systems into space to carry out the first tests. They were launched from the Uchinoura Space Center aboard the S-520-31, a single-stage rocket capable of lofting a 220 lbs (100 kg) payload well above 186 miles (300 km). After recovering the rocket from the ocean, the JAXA team of engineers analyzed the data and confirmed the success of the mission, which put the new system at an estimated altitude of (146 miles) 234.9 km.

The rotating detonation engine uses a series of controlled explosions that travel around an annular channel in a continuous loop. This process generates a large amount of super-efficient thrust coming from a much smaller engine using significantly less fuel – which also means sending less weight on a space launch. According to JAXA, it has the potential to be a game-changer for deep space exploration.

The rocket began the test demonstrations after the first stage separated, burning the rotating detonation engine for six seconds, while a second pulse detonation engine operated for two seconds on three occasions. The pulse engine uses detonation waves to combust the fuel and oxidizer mixture.

When the rocket was recovered after the demonstration, it was discovered that the rotary engine produced about 500 Newtons of thrust, which is only a fraction of what conventional rocket engines can achieve in space.

According to JAXA engineers, the successful in-space test has greatly increased the possibility that the detonation engine will be used in practical applications, including in rocket motors for deep space exploration, first-stage, and two-stage engines, and more. The engines could indeed allow us to travel deep into space using a fraction of the fuel and weight, which will be critical in interplanetary journeys.

Study Uncovers Mysterious Radio Objects, Some Hard to Explain

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#space #astronomy #radioobjects #radioastronomy #FRB #LOFARreadioastronomy

FM radio waves reveal a side of the universe invisible to the human eye.

The Hercules A black hole jets captured in a high-resolution image captured by the LOFAR radio telescope. The images revealed that the jet grows stronger and weaker every few hundred thousand years. This variability produced the structure of the jet.

The Hercules A black hole jets captured in a high-resolution image captured by the LOFAR radio telescope. The images revealed that the jet grows stronger and weaker every few hundred thousand years. This variability produced the structure of the jet. (Image credit: R. Timmerman; LOFAR & Hubble Space Telescope)

The most detailed radio images of galaxies outside the Milky Way have been captured by a network of 70,000 radio antennas spread over nine European countries.

The images reveal a side of the universe invisible to optical telescopes and provide a glimpse into some of the most mysterious cosmic phenomena, such as the activity of supermassive black holes at galactic centers. 

A team of astronomers behind the Low Frequency Array (LOFAR), a radio telescope network managed by the Netherlands Institute for Radio Astronomy (Astron), worked for 10 years to produce the images. 

Leah Morabito, assistant professor of physics at the University of Durham in England, led the effort to improve the standard resolution of LOFAR images. By including more antennas and with the help of supercomputers, they improved the resolution by a factor of 20. 

Morabito told Space.com in an email that the images provide the highest-ever resolution in the FM radio frequency band, a band between 88 to 108 megahertz that is used for radio broadcasting on Earth. The biggest accomplishment, however, was being able to combine this high resolution with a wide field of view, she added. 

“That’s totally unique,” Morabito said. “It will allow us to survey the entire northern sky in just a few years. Telescopes with comparable resolution have a field of view almost 20 times smaller, and therefore an all-sky survey isn’t logistically possible. No other current or planned radio telescope will have this combination of field of view and resolution.”

Celestial objects including stars, some planets and black holes emit radio waves, which are not visible to optical telescopes. Unlike visible light, these radio waves penetrate through clouds of dust and gas, revealing a picture of the universe that would otherwise be hidden. 

The GIF shows the difference between standard resolution images and the new high resolution images captured by the radio telescope LOFAR.
(Image credit: L.K. Morabito; LOFAR Surveys KSP)

Supermassive black holes are among the most powerful sources of radio waves in the universe. The LOFAR imaging campaign therefore focused on them, looking for jets of material ejected from these black holes, which can’t be detected in the optical spectrum.

“These high-resolution images allow us to zoom in to see what’s really going on when supermassive black holes launch radio jets, which wasn’t possible before at frequencies near the FM radio band,” Neal Jackson of the University of Manchester in England, who cooperated on the project, said in a statement issued by Astron.

LOFAR usually uses only antennas in the Netherlands. But that limits the diameter of the virtual telescope’s lens to only 75 miles (120 kilometers). The diameter of the telescope, in turn, limits its resolution. 

A galaxy imaged by the LOFAR radio telescope.
A galaxy imaged by the LOFAR radio telescope. (Image credit: LOFAR)

The astronomers, however, found a way to integrate antennas in nine European countries, which enabled them to increase the diameter to 1,200 miles (2,000 km) and achieve 20 times better resolution. 

Observations made by the individual antennas were digitized and combined into the final high-resolution images. But that was no easy feat. The scientists had to process 1.6 terabytes of data per second, an equivalent of more than 300 DVDs.

“To process such immense data volumes, we have to use supercomputers,” Frits Sweijen of Leiden University in the Netherlands, said in the statement. “These allow us to transform the terabytes of information from these antennas into just a few gigabytes of science-ready data, in only a couple of days.” 

Morabito added that it would take 3,000 observations to image the entire northern sky. The images and the scientific papers they spawned were published in a special edition of the journal Astronomy and Astrophysics on Tuesday (Aug 17).

Are we ready for another Carrington Level Event?

#Carrington #Level #SolarStorm #CME #space #astronomy

Preparedness is one of those attributes which has been sorely tested in recent times and in many ways has been found wanting but there are many bullets out there with our name potentially on them, one of which we have touched on before, namely solar storms and the CME or coronal mass ejections that usually follow shortly afterwards. These have the potential to create havoc with our modern technological lifestyle, not only affecting satellites but also power generation and all the knock-on effects that losing either of these could bring, one of them even affected the operations of the US navy in the Vietnam war, so I thought that it would interesting just how prepared we are and would it really be as bad as the popular media makes out.

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Just as the earth has weather, so does the sun, but on a much, much larger scale and were as our weather systems are restricted to the earth, the suns weather affects the whole solar system and when the sun sneezes in our direction we catch a cold.

The earth is exposed to a continuous stream of energetic charged particles called the solar wind that travel at up to 3.2 Million km/h and flow out into the solar system to well beyond the outer planets.

As these particles are affected by magnetism, some are trapped by the earth’s magnetic field and channelled to the poles where they interact with the oxygen and nitrogen in the upper atmosphere to create the auroras or the northern and southern lights

Now the sun rotates once every 27 days but different areas of the sun rotate at differing speeds, this causes the suns magnetic field to twist and contort.

The sun also goes through cycles of activity approximately every 11 years. During the periods of peak activity, the solar maximum, disturbances on the suns surface called sunspots become much more common. Along with these are more violent disturbances called a solar flares.

If the Flare is powerful enough it will often eject huge quantities of plasma or charged particles that make up the suns surface or corona, these are called Coronal Mass Ejections or a CME’s.

During a solar flare, initially, there is a sudden burst of x-rays and ultraviolet light which reaches earth in about 8 minutes, this interacts with the ionosphere to affect radio communications.

About 30 mins later a flood of high energy electrons and protons travelling at nearly the speed of light hit the Earths magnetic field and any spacecraft that are outsides its protection. This can cause computer errors and failures of electronic circuits causing satellites to glitch or fail and expose astronauts to high levels of ionising radiation. These charged particles are drawn into the magnetosphere and channelled to the poles creating intense auroras that can be seen much farther from the poles than normal.

In the most violent solar flares, huge magnetic loops bulge out from the suns surface that are many times the size of the earth. When these loops break a billion tons or so of plasma are ejected into space, this is the coronal mass ejection. If the Earth is in the wrong place at the wrong time then this along with a part of the suns magnetic field will come barreling through space to hit us in between about 14 to 40+ hours later.

It’s the polarity of the CME’s magnetic field which can do so much damage when it gets to earth. If it is opposite to the earth’s magnetosphere, the two are drawn together just like two magnets, dumping energy all around the earth. If they are the same then they will repel each other and the damage will be much less.

The problem is that CME’s travel at a very high speed and it’s only in the last 15 minutes that we know what their polarity is so that leaves very little time in which to prepare.  

When a large CME hits the Earths magnetic field, its a bit like a hammer hitting a bell, the magnetic field rings, compressing and stretching and when a magnetic field lines break the charged particles trapped in it travel back down to the earth creating arouras and inducing electrical currents into the Earths surface and anything running over it like powerlines.

Ones that run north to south, parallel to the Earths magnetic field are the most affected, those that run east to west are less so.

This fluctuating magnetic field can induce DC voltages into the high voltage AC power lines causing the step-down transformers to saturate and overheat and burn out in a matter of seconds. To help protect the transformers against geomagnetically induced currents, giant capacitors that block DC but allow AC to flow are installed. However series capacitors are very expensive and while they may protect one power line, the DC could end up rerouted and concentrated into unprotected lines causing more damage than if capacitors weren’t used.

Although there are backups if too may fail then entire grids can shut down. Because there is much more interconnectivity than ever before with smaller grids sometimes from other countries linked together to form super grids, a shut down in one area could ripple through and cause power outages hundreds to thousands of kilometres away.

CME’s hit the earth all the time with about 2 on average per week but these are small and we bearly notice them. Its when a really big one comes along that we are in for a problem. We have now been watching the sun for long enough to know that the largest the sun can produce would be about 3 times the largest we have seen so far but these are extremely rare, in the order of one every few thousand years.

The first recorded CME to cause us a problem was the “Carrington Event”.  A super solar flare seen by the British astronomer Richard Carrington on the 1st Sept 1859. Over the next couple of days there were reports of amazing auroral displays as the northern lights reached as far south as Mexico, Cuba and Hawaii and the Southern lights as far north as Queensland, Australia.

The CME reached the earth 17.6 hours after Carrington saw the initial flare which was quicker than the usual day or two. This is because CME’s sometimes come in a series of bursts with the first usually being smaller but clearing the way of cosmic debris allowing the following ones to arrive faster.

As there was very little in the way of electrical infrastructure at the time, the Telegraph system was the first to show the electrical effects with sparks jumping from switches, shocking the operators and even powering sections of routes when the battery power was removed.

There have been several superstorms since the Carrington event, though none as large but the one which stands out was the March 1989 geomagnetic storm which blacked out large parts of Canada and very nearly blacked out the northeastern United States. This is memorable because it was first have a big impact on our modern infrastructure and it revealed the very real threat that space weather and things like CME’s could have here on Earth.

Since then our power usage has increased but so has our understanding of how solar storms affect us here on earth with much of this data coming from a lucky escape the earth had in 2012, more on that in a moment.

Geomagnetic storms and CME’s are measured using the DST or the Disturbance storm time index, in fact it’s only been since 1957 that we have had proper records of the DST, before then we had to rely on a few magnetometers scattered around the globe.

The DST index measures the ring current around the earth which is created by solar protons and electrons trapped by the Earths magnetosphere. The Ring current produces a magnetic field that protects the lower latitude regions around the equator but is also opposite to the Earths magnetic field, so during geomagnetic storms and CME’s, an increase in the amount of charged particles being trapped here weakens the Earths geomagnetic field.

The DST is measured in NanoTeslas, the lower the negative DST value the weaker the Earths magnetic field and the more the earth is affected by the solar storm.

The typical quite time measurement of DTS is between plus and minus 20nT. An intense geomagnetic storm might decrease that to around -300nT, the Carrington event was believed to have been between -900 and -1750 nT. The reason for this wide range was because of the very limited data that was recorded in 1859 so much of it has to be guestimated from the observations of things like auroras at the time.

Although DST is a good measure for recording events, for measuring realtime changes in the magnetic field like the electrical gid companies need to know, the Kp-index is used. This uses continuous measurements from 13 different measuring stations in the auroral zones around the world. The Kp index utilises a quasi-logarithmic scale of 1 to 9, where 1 is calm, 5 is a solar storm and 9 is an extreme solar storm.

The map above shows you what the Kp-index would be needed to be to see the aurora overhead at a given location.

Now In 2012 we dodged a “Carrington Event” sized bullet when a -1200 nT CME crossed the earth’s orbit, the lucky thing for us was that it was a week late, if it had happened 7 days earlier it would have been a direct hit but it did hit probably the best-equipped satellite for this very issue, the STEREO A solar observatory.

This is one of two nearly identical satellites designed to image the sun and in particular things like solar storms and CME’s. The data collected from this event gave us a huge amount of information and greatly increased our knowledge on how to protect our earth based systems.

Whilst a large CME will be big enough to completely engulf the earth, where you live can have a major impact on how bad the effects could be.

One of the reasons why Canada was affected so much by the 1989 solar storm was that the long stretches of power lines they have, the longer the lines the more electrical energy can be induced into them but it now been discovered that the type of rock the lines run over can also make a big difference.

Its not just metal power cables that the magnetic disturbance can induce power into it’s the ground its self.  

In recent years it has been found that the type of rocks under where you live can magnify the effect a CME can have on things like the power grid by up to 100 times. Igneous and metamorphic rocks have a very high electrical resistance while sedimentary rocks which have water in them have a very low electrical resistance and allow electrical currents induced into them to flow.

Now whilst it might seem that a highly resistive rock like Igneous and metamorphic ones would be a good thing, they act like a giant insulator but the power lines that cross them provide a short circuit through their ground connection allowing currents to build up and flow through them to damage things like transformers. The North Eastern US was also badly hit by the 1989 storm and was on the verge of a shut down and again much of that area is covered by the Appalachian mountain range which is Igneous and metamorphic in its makeup.

In the United Kingdom, the highland area of Scotland is igneous and metamorphic rock where as the farther south east you go in England they are mostly sedimentary rocks, so Scotland could be affected much more than England.

In recently declassified US Navy documents,  the crew of a US Task Force 77 aircraft saw a group of 20-25 magnetic sea mines which were laid by the US off the coast of Vietnam at Hai Phong, detonate over a 30 second period on August 4th 1972.  At the time there was no obvious reason as to why this should have happened. The mines had a self destruct time built time but that was not for another 30 days or so.

However, the US Navy noticed that an X-class solar flare had been detected earlier that day and in a record 14.6 hours a CME hit the Earth. Although the DST value was only -125Nt, its thought that the speed at which it hit the Earths magnetosphere caused it to compress in a similar way to a larger storm and it was this rapid change in the earth’s magnetic field that triggered the magnetic mines.

By mapping the resistance of the rocks and the local magnetic hot spots in the US and other countries its possible to work out where large currents could build up and thus to make provisions in the power grid connectivity.

In the UK the National Grid has been replacing high voltage transformers with newer designs that are more resilient to extra current surges. The strategy in the UK is that if large CME is expected and the polarity is opposite to the earths, they will turn on as much of the 8000km of the UK power lines as possible to dump energy over the entire system and drain it back to earth rather than allowing it to overload a few key system areas and causing costly and lengthy repairs.

Places like the US, Canada and even Australia where there are very long high voltage cable runs which run north to south over varying geologies are more susceptible. Even with blocking capacitors installed, early warnings from satellite observations will be key to knowing which parts might be affected more than others and as such which to protect or temporarily shut down to avoid long term damage.

With our much-increased knowledge of how solar weather affects us here on earth and how the earth its self reacts, it much less likely that even a Carrington class event would have much impact on the countries like the UK which have prepared for this kind of situation but in the end, it’s down to the individual countries and their power companies to make sure that when that once in a hundred year CME comes along the lights won’t go out.

Space collision: Chinese satellite got whacked by hunk of Russian rocket

#Space #collision #Chinese #satellite #Russian #rocket

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In March, the U.S. Space Force’s 18th Space Control Squadron (18SPCS) reported the breakup of Yunhai 1-02, a Chinese military satellite that launched in September 2019. It was unclear at the time whether the spacecraft had suffered some sort of failure — an explosion in its propulsion system, perhaps — or if it had collided with something in orbit.

We now know that the latter explanation is correct, thanks to some sleuthing by astrophysicist and satellite tracker Jonathan McDowell, who’s based at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
On Saturday (Aug. 14), McDowell spotted an update in the Space-Track.org catalog, which the 18SPCS makes available to registered users. The update included “a note for object 48078, 1996-051Q: ‘Collided with satellite.’ This is a new kind of comment entry — haven’t seen such a comment for any other satellites before,” McDowell tweeted on Saturday.

He dove into the tracking data to learn more. McDowell found that Object 48078 is a small piece of space junk — likely a piece of debris between 4 inches and 20 inches wide (10 to 50 centimeters) — from the Zenit-2 rocket that launched Russia’s Tselina-2 spy satellite in September 1996. Eight pieces of debris originating from that rocket have been tracked over the years, he said, but Object 48078 has just a single set of orbital data, which was collected in March of this year.

“I conclude that they probably only spotted it in the data after it collided with something, and that’s why there’s only one set of orbital data. So the collision probably happened shortly after the epoch of the orbit. What did it hit?” McDowell wrote in another Saturday tweet.

Yunhai 1-02, which broke up on March 18, was “the obvious candidate,” he added — and the data showed that it was indeed the victim. Yunhai 1-02 and Object 48078 passed within 0.6 miles (1 kilometer) of each other — within the margin of error of the tracking system — at 3:41 a.m. EDT (0741 GMT) on March 18, “exactly when 18SPCS reports Yunhai broke up,” McDowell wrote in another tweet.
Thirty-seven debris objects spawned by the smashup have been detected to date, and there are likely others that remain untracked, he added.

Despite the damage, Yunhai 1-02 apparently survived the violent encounter, which occurred at an altitude of 485 miles (780 kilometers). Amateur radio trackers have continued to detect signals from the satellite, McDowell said, though it’s unclear if Yunhai 1-02 can still do the job it was built to perform (whatever that may be).
McDowell described the incident as the first major confirmed orbital collision since February 2009, when the defunct Russian military spacecraft Kosmos-2251 slammed into Iridium 33, an operational communications satellite. That smashup generated a whopping 1,800 pieces of trackable debris by the following October.

However, we may be entering an era of increasingly frequent space collisions — especially smashups like the Yunhai incident, in which a relatively small piece of debris wounds but doesn’t kill a satellite. Humanity keeps launching more and more spacecraft, after all, at an ever-increasing pace.

“Collisions are proportional to the square of the number of things in orbit,” McDowell told Space.com. “That is to say, if you have 10 times as many satellites, you’re going to get 100 times as many collisions. So, as the traffic density goes up, collisions are going to go from being a minor constituent of the space junk problem to being the major constituent. That’s just math.”

We may reach that point in just a few years, he added.

The nightmare scenario that satellite operators and exploration advocates want to avoid is the Kessler syndrome — a cascading series of collisions that could clutter Earth orbit with so much debris that our use of, and travel through, the final frontier is significantly hampered.
Our current space junk problem is not that severe, but the Yunhai event could be a warning sign of sorts. It’s possible, McDowell said, that Object 48078 was knocked off the Zenit-2 rocket by a collision, so the March smashup may be part of a cascade.

“That’s all very worrying and is an additional reason why you want to remove these big objects from orbit,” McDowell told Space.com. “They can generate this other debris that’s smaller.”

Small debris is tough to track, and there’s already a lot of it up there. About 900,000 objects between 0.4 inches and 4 inches wide (1 to 10 cm) are whizzing around our planet, the European Space Agency estimates. And Earth orbit hosts 128 million pieces of junk 0.04 inches to 0.4 inches (1 mm to 1 cm) in diameter, according to ESA.

Orbiting objects move so fast — about 17,150 mph (27,600 kph) at the altitude of the International Space Station, for example — that even tiny shards of debris can do serious damage to a satellite.

Rare Natural Event in Alaska Sees 3 Volcanoes Erupting at The Same Time

#Alaska #Volcanoes #Eruption #disaster #Aleutian

Three volcanoes in the Alaskan chain of Aleutian islands are currently erupting, and two others are rumbling with disquiet.

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According to a report by NBC, it’s been at least seven years since three Aleutian volcanoes erupted simultaneously. This increased volcanic activity, at this point, is not causing any disruptions, but it is an interesting situation; since volcanoes can be unpredictable, scientists are keeping a careful watch.

The Great Sitkin volcano, Mount Pavlof, and the Semisopochnoi volcano are all at an orange volcano alert level as of Sunday 15 August, according to the Alaska Volcano Observatory.

This means that eruptions are currently underway, but they’re relatively small, rumbly ones with minimal ash.

Only minute amounts of ash have been detected at Mount Pavlof and Semisopochnoi, and none from Great Sitkin. However, lava is flowing from Great Sitkin, and large seismic tremors and several explosions have been detected at Semisopochnoi.

In addition, Mount Cleveland and the volcanic complex on Atka have been showing signs of activity – increased heat under Mount Cleveland, and small earthquakes under Atka. Both are at a yellow volcano alert level.

Although such simultaneous volcanic activity in the Aleutians is uncommon, it’s not unheard of. The Aleutian Arc is a chain of volcanoes spread along the subduction boundary between two tectonic plates – the Pacific Plate pushing beneath the North American Plate. The chain stretches from the Alaskan Peninsula to the Kamchatka Peninsula in Russia.

Often when volcanoes erupt, other nearby volcanoes in close proximity can be roused, but it’s not always clear why. The Aleutian Arc is home to a different kind of mystery.

In 1996, volcanic and seismic activity was spread across 870 kilometers (540 miles) of the arc, which scientists concluded had to be more than coincidental, although the trigger is unknown.

In this case, it’s not entirely clear what’s going on either. Nearly 290 kilometers (180 miles) span between the two outermost volcanoes in this spate of activity, Great Sitkin and Semisopochnoi.

Last year, researchers found that a collection of volcanoes along the Aleutian Arc may be part of a larger supervolcano, but only one of the currently rumbly beasts, Mount Cleveland, is among the specified group.

Although there’s nothing to worry about at this point, the event could turn out to be very scientifically interesting.

Geologists and volcanologists will no doubt be monitoring the situation to see if they can find a link to earlier outbreaks of simultaneous activity, and to try to learn more about this mysterious arc of volcanoes.

Is Ganymede – Not Mars Or Europa – The Best Place To Look For Alien Life?

This could be a trend for icy bodies throughout the solar system and beyond.

#ganymede #space #alien #life #jupiter

The Jupiter moon Ganymede, the largest satellite in the solar system, as seen by NASA’s Voyager 2 spacecraft on July 7, 1979, from a distance of 745,000 miles (1.2 million kilometers).

The Jupiter moon Ganymede, the largest satellite in the solar system, as seen by NASA’s Voyager 2 spacecraft on July 7, 1979, from a distance of 745,000 miles (1.2 million kilometers). (Image credit: NASA)

In the wisp-thin sky of Jupiter’s moon Ganymede, the largest satellite in the solar system, astronomers have for the first time detected evidence of water vapor, a new study finds.

The discovery could shed light on similar watery atmospheres that may envelop other icy bodies in the solar system and beyond, researchers said.

Previous research suggested that Ganymede — which is larger than Mercury and Pluto, and only slightly smaller than Mars — may contain more water than all of Earth’s oceans combined. However, the Jovian moon is so cold that water on its surface is frozen solid. Any liquid water Ganymede possesses would lurk about 100 miles (160 kilometers) below its crust.

Prior work suggested that ice on Ganymede’s surface could turn from a solid directly to a gas, skipping a liquid form, so that water vapor could form part of the giant moon’s thin atmosphere. However, evidence of this water has proved elusive — until now.

In the new study, researchers analyzed old and new data of Ganymede from NASA’s Hubble Space Telescope. In 1998, Hubble captured the first ultraviolet images of Ganymede, including pictures of its auroras, the giant moon’s versions of Earth’s northern and southern lights. Colorful ribbons of electrified gas within these auroras helped provide evidence that Ganymede has a weak magnetic field.

Ultraviolet signals detected in these auroral bands suggested the presence of oxygen molecules, each made of two oxygen atoms, which are produced when charged particles erode Ganymede’s icy surface. However, some of these ultraviolet emissions did not match what one would expect from an atmosphere of pure molecular oxygen. Previous research suggested these discrepancies were linked to signals from atomic oxygen — that is, single atoms of oxygen.

As part of a large observing program to support NASA’s Juno mission to Jupiter, researchers sought to measure the amount of atomic oxygen in Ganymede’s atmosphere using Hubble. Unexpectedly, they discovered there is hardly any atomic oxygen there, suggesting there must be another explanation for the earlier ultraviolet signals.

The scientists focused on how the surface temperature of Ganymede varies strongly throughout the day, with highs of about minus 190 degrees Fahrenheit (minus 123 degrees Celsius) at noon at the equator and lows of about minus 315 degrees Fahrenheit (193 degrees Celsius) at night. At the hottest spots on Ganymede, ice may become sufficiently warm enough to convert directly into vapor. They noted that differences seen between a number of ultraviolet images from Ganymede closely match where one would expect water in the moon’s atmosphere based on its climate.

“Water vapor in the atmosphere matches the data very well,” study lead author Lorenz Roth, a planetary scientist at the KTH Royal Institute of Technology in Stockholm, told Space.com.

The main reason previous research failed to detect water in Ganymede’s atmosphere is because the ultraviolet signal from molecular oxygen is very strong. “Within this stronger oxygen signal, it’s hard to find other signals,” Roth said.

“These findings suggest that water vapor actually exists in the atmospheres of icy bodies in the outer solar system,” Roth said. “Now we might see it more places.”

The scientists detailed their findings online Monday (July 26) in the journal Nature Astronomy.

Asteroid Bennu Earth impact probability increases

#OSIRIS-Rex #Bennu #Earthimpact #space #astronomy #asteroid

Asteroid Bennu is one of the two most hazardous known asteroids in our Solar System. Luckily, the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) spacecraft orbited Bennu for more than two years and gathered data that has allowed scientists to better understand the asteroid’s future orbit, trajectory and Earth-impact probability, and even rule out some future impact possibilities.

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In the most precise calculations of an asteroid’s trajectory ever made, researchers determined Bennu’s total impact probability through the year 2300 is really small — about 1 in 1,750 (or 0.057%). The team’s paper says the asteroid will make a close approach to Earth in 2135, where Bennu will pose no danger at that time. But Earth’s gravity will alter the asteroid’s path, and the team identifies Sept. 24, 2182 as the most significant single date in terms of a potential impact, with an impact probability of 1 in 2,700 (or about 0.037%).

“The impact probability went up just a little bit, but it’s not a significant change,” said Davide Farnocchia, lead author of the paper, and scientist at the Center for Near Earth Object Studies at NASA’s Jet Propulsion Laboratory, speaking at a press briefing this week. Farnocchia added that means there is a 99.94% probability that Bennu is not on an impact trajectory.

“So, there is no particular reason for concern,” he said. “We have time to keep tracking the asteroid and eventually come to a final answer.”

101955 Bennu was discovered in 1999 by the Lincoln Near-Earth Asteroid Research Team. Since its discovery, Bennu has been extensively tracked with 580 ground-based optical astrometric observations. The asteroid made three relatively close passes of Earth in 1999, 2005, and 2011, during which the Arecibo and Goldstone radar stations collected a wealth of data about Bennu’s motion.

OSIRIS-REx discovered particles being ejected from asteroid Bennu shortly after arriving at the asteroid. Image Credit: NASA/Goddard/University of Arizona/Lockheed Martin

But OSIRIS-REx’s two-year reconnaissance and sample collection has provided crucial data about the 500-meter-wide asteroid, including some surprises. Scientists expected Bennu’s surface to be smooth and sandy, but the first images from OSIRIS-REx revealed a rugged boulder-field, littered with large rocks and loose gravel. The team also expected the asteroid to be geologically quiet, but just six days after arriving in orbit, the spacecraft observed the asteroid ejecting bits of rock, due to rocks on the asteroid cracking because of the day-night heat cycle. We also learned that Bennu has pieces of Vesta on it. The spacecraft also scooped up a sample of rock and dust from the asteroid’s surface in October of 2020, which it will deliver to Earth on Sept. 24, 2023, for further scientific investigation.

But OSIRIS-REx’s precise observations of Bennu’s motions and trajectory allowed for the best estimate yet of the asteroid’s future path.

“The OSIRIS-REx mission has provided exquisitely precise data on Bennu’s position and motion through space to a level never captured before on any asteroid,” said Lindley Johnson, planetary defense officer at NASA’s Planetary Defense Coordination Office at NASA.

The researchers took into account all kinds of small influences, including the tiny gravitational pull of more than 300 other asteroids, and the drag caused by interplanetary dust. They even checked to see if OSIRIS-REx pushed the asteroid off course when the spacecraft briefly touched its rocky surface with its Touch-And-Go (TAG) sample collection maneuver. But that event had a negligible effect, as expected.

The researchers especially focused on a phenomenon called the Yarkovsky effect, where an object in space would, over long periods of time, be noticeably nudged in its orbit by the slight push created when it absorbs sunlight and then re-emits that energy as heat. Over short timeframes, this thrust is minuscule, but over long periods, the effect on the asteroid’s position builds up and can play a significant role in changing an asteroid’s path.

“The Yarkovsky effect will act on all asteroids of all sizes, and while it has been measured for a small fraction of the asteroid population from afar, OSIRIS-REx gave us the first opportunity to measure it in detail as Bennu travelled around the Sun,” said Steve Chesley, senior research scientist at JPL and study co-investigator, in a press release. “The effect on Bennu is equivalent to the weight of three grapes constantly acting on the asteroid – tiny, yes, but significant when determining Bennu’s future impact chances over the decades and centuries to come.”

A diagram showing OSIRIS-REx’s sampling maneuver on October 20th, 2020. Image Credit: NASA/GSFC/UA

They also were able to better determine how the asteroid’s orbit will evolve over time and whether it will pass through a “gravitational keyhole” during its 2135 close approach with Earth. These keyholes are areas in space that would set Bennu on a path toward a future impact with Earth if the asteroid were to pass through them at certain times, due to the effect of Earth’s gravitational pull.

The team wrote in their paper that “compared to the information available before the OSIRIS-REx mission, the knowledge of the circumstances of the scattering Earth encounter that will occur in 2135 improves by a factor of 20, thus allowing us to rule out many previously possible impact trajectories.”

“The orbital data from this mission helped us better appreciate Bennu’s impact chances over the next couple of centuries and our overall understanding of potentially hazardous asteroids – an incredible result,” said Dante Lauretta, OSIRIS-REx principal investigator and professor at the University of Arizona. “The spacecraft is now returning home, carrying a precious sample from this fascinating ancient object that will help us better understand not only the history of the solar system but also the role of sunlight in altering Bennu’s orbit since we will measure the asteroid’s thermal properties at unprecedented scales in laboratories on Earth.”

Manned version of X-37 space plane in the works?

X-37B on runway at Vandenberg AFB (Image: USAF)

X-37B on runway at Vandenberg AFB (Image: USAF)VIEW 13 IMAGES

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#X37B #X37C #NASA #Space #Spaceplane #Shuttle #Boeing

When the Space Shuttle Atlantis touched down for the final time on July 21, 2011, it looked as if the notion of a manned spacecraft capable of going into orbit and then landing like a conventional airplane had been abandoned. The US government appears to be in favor of returning to Apollo-style space capsules with anything like the Shuttles being relegated to the private sector. But at the American Institute of Aeronautics and Astronautics’ (AIAA) recent Space 2011 conference, Arthur Grantz, chief engineer of Space and Intelligence Systems’ Experimental Systems Group at Boeing, delivered a paper indicating that the U.S. Air Force and Boeing are already on the way toward developing a manned Shuttle replacement based on the X-37B robot space plane.


The X-37B is one of the US Air Force’s most highly visible yet most secret projects of recent years. A robot spacecraft that looks like a miniature space shuttle without a flight deck was bound to attract public attention, but its mission has remained hidden under the blanket word “classified.” The government has released some information about the X-37B. In part, it’s an experimental test bed based on the Boeing X-40 lifting body. With an overall length of a little under 30 ft (9 m) and a wing span just under 15 ft (4.5 m), it’s small enough to fit easily into the Shuttle’s cargo bay, but it’s still capable of acting like a robot version of the larger, older spacecraft. Launched on top of an Atlas booster at Vandenberg Air Force Base, it can carry payloads into space, return them to earth and then land like a conventional aircraft. The difference is that it doesn’t require a pilot or ground control because it can land by itself.

It also has much more endurance than the old Shuttle. While the Shuttle never remained in orbit for as long as three weeks, the X-37B has already broken the record for a reusable spacecraft in orbit: 244 days. It’s rated to remain on station for 270 days if needed.

Shrouded in Secrecy

But for all that the public knows about the X-37B’s capabilities, its mission remains a secret. Part of the X-37B’s purpose is experimenting with new technologies and it’s clear that the Air Force wants its own way of getting into and coming back from space. What they intend to do once in orbit is another question. One thing that the X-37 is designed for is to release satellites that it can rendezvous with at a later date and retrieve. With today’s cyber-heavy battlefields, that is a considerable advantage. Beyond that, the space plane configuration echoes the Air Force’s earlier Dyna Soar program of the early 1960s, which was also a space plane (in this case manned) intended to be launched from atop a booster rocket. Its purpose was supposed to be as a hypersonic reconnaissance platform and bomber-roles that a variant of the X-37 could also fulfill.


The paper that Grantz delivered to the AIAA, “X-37B Orbital Test Vehicle and Derivatives” [PDF summary], provides further insights into the X-37 including the possibility of a manned version. Grantz says that the X-37B’s successor, the larger X-37C, could be used as a cargo ship for the International Space Station. There are already several spacecraft in service and under development that could do that, but Grantz says that the X-37C could also be easily modified to carry up to six passengers. Unlike other cargo carriers slated to become manned spacecraft, this doesn’t necessarily require major design changes. One proposed version of the X-37 shows the interior significantly altered with the fuel tanks and operating systems pushed aft to make way for a traditional flight deck in the bow, but the alternative is simply to place a self-contained pressurized cylinder in the cargo bay and install television cameras fore and aft so the crew can see what’s going on.

X-37B size comparison (Image: USAF)
X-37B size comparison (Image: USAF)

This “plug and play” feature speaks volumes about the X-37 and the X-37C in particular. Human beings are fragile creatures and space engineers have to bear in mind that the human body can only tolerate a narrow range of variables. Too heavy acceleration on takeoff, too sharp a turn, too much vibration or too hard a landing can injure or kill a person. The X-37 is what is called a “1.5 g” spacecraft. In other words, it operates only within an acceleration range of one and a half times the pull of Earth’s gravity. This means that it can carry delicate instruments into space and return them safely to the ground. It also means that it operates safely within the range of what is called “man rated” or “human rated” flight.

What’s also implied by being human rated is that the craft has a mandatory failure ratio of less than one percent. Unmanned spacecraft are allowed a failure rate of ten percent. Moreover, the ability of the X-37 to launch and retrieve satellites as well as to land autonomously suggests a navigation and guidance system sophisticated enough for manned flight that can be adapted for the option of manual control that a human rating requires.

The future of the X-37 program is not certain, but the fact that a new manned spacecraft can be the result of modifying existing technology rather than starting from scratch shows that the grounding of the Shuttle fleet wasn’t just the end of an era, it was the start of a new one.

Why won’t Starship share the fate of the Space Shuttles?

#Starship #SpaceShuttle #NASA #SpaceX #Heatshield

Many of you probably know the Space Shuttle Columbia disaster, in which 7 NASA astronauts lost their lives while preforming re-entry maneuver after a successful orbiter mission. The disaster was caused by damage to the heat shield from a piece of foam detached from the main fuel tank two weeks before the crash, during Columbia’s launch from Kennedy Space Center.

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Heat shields have been a pain in the Space Shuttle from the beginning. It was the thermal

protection that caused the shuttles to fly a maximum of 4 times a year, and their launch cost was over 1.5 billion dollars.

So what about these shields?

The shuttle was made mostly of fast-melting aluminum, so every square millimeter of the leading site had to be protected to prevent disaster. Unfortunately, the shuttle, as a vehicle that uses the physics of flight and has wings to create aerodynamic force, had a very complicated geometry. So complicated that it needed hundreds, if not thousands, of different types of TPS tiles. Additionally, the time required to install one tile was approximately 40 hours.

If that wasn’t enough, the placement of the tiles on the shuttle’s structure was very complicated. One reason for this is the high expansion of aluminum when heated. There was a possibility that the tile would just pop off. The way the space shuttle and rocket were configured for launch also left much to be desired.

The shuttle flew into space attached to a large tank of foam insulation with a heat shield facing it. As a result, a piece of ice or foam detached from the main tank was enough to literally tear the tile out of the fastening at supersonic speeds.

NASA didn’t fix the problem until the end of the shuttle program in 2011, even though it costed the lives of 7 people and endangered virtually all of the astronauts who flew the vehicle. The preventative measure turned out to be a heat shield inspection by… astronauts on the ISS! The shuttle rotated 180 degrees and you coul review the condition of its tiles before returning to Earth.

Okay, we know what went wrong. So how is SpaceX going to take the consequences of the Space Shuttle program and create the true reusable vehicle that NASA so desperately wanted?

The whole thing can be divided into several subsections:

– One: Ship has a less complex geometry. Except for the four flaps, it’s a regular roller. It doesn’t need to soar, only slow down on landing, so it doesn’t need complicated wings, tail, stabilizers, and a contoured beak.

– Two: In the event that a tile falls off, the Ship has a good chance of surviving re-entry into the atmosphere and returning safely to Earth. That’s because the SpaceX vehicle is made of stainless steel instead of aluminum, so without heat shields, it can withstand more than twice the temperature.

– Three: Lower temperature expansion of steel relative to aluminum. This ensures that the changes in mechanical stress are small, making the tiles less likely to detach from the vehicle.

– Four: Ship’s simple tile mounting system. The heat-insulating mat allows some of the heat to be absorbed and the clip system means that each tile should take literally minutes to install. Additionally, the tile mounts are designed in such a way that each tile has some play, which should prevent the tiles from cracking during the temperature swings they experience during flight.

– Five: Steel has another interesting property when re-entering the atmosphere: when the windward side covered with thermal plates absorbs as much heat as possible, the heated plasma flows around the Ship’s sides and heats the leeward side. In Space Shuttles, this side was painted white to most effectively reflect heat radiation into space. The ship needs no such treatment, as it just so happens that steel itself is an almost perfect heat reflective material!

Considering the above changes, I’m sure SpaceX has learned from the failure of the STS program.

‘Time is elastic’: Why time passes faster atop a mountain than at sea level

#Time #Physics #Elastic #Science #spacetime

The idea of ‘absolute time’ is an illusion. Physics and subjective experience reveal why.

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‘Time is elastic’: Why time passes faster atop a mountain than at sea level


  • Since Einstein posited his theory of general relativity, we’ve understood that gravity has the power to warp space and time.
  • This “time dilation” effect occurs even at small levels.
  • Outside of physics, we experience distortions in how we perceive time — sometimes to a startling extent.

Place one clock at the top of a mountain. Place another on the beach. Eventually, you’ll see that each clock tells a different time. Why? Time moves slower as you get closer to Earth, because, as Einstein posited in his theory of general relativity, the gravity of a large mass, like Earth, warps the space and time around it.

Scientists first observed this “time dilation” effect on the cosmic scale, such as when a star passes near a black hole. Then, in 2010, researchers observed the same effect on a much smaller scale, using two extremely precise atomic clocks, one placed 33 centimeters higher than the other. Again, time moved slower for the clock closer to Earth.

The differences were tiny, but the implications were massive: absolute time does not exist. For each clock in the world, and for each of us, time passes slightly differently. But even if time is passing at ever-fluctuating speeds throughout the universe, time is still passing in some kind of objective sense, right? Maybe not.

Physics without time

In his book “The Order of Time,” Italian theoretical physicist Carlo Rovelli suggests that our perception of time — our sense that time is forever flowing forward — could be a highly subjective projection. After all, when you look at reality on the smallest scale (using equations of quantum gravity, at least), time vanishes.

“If I observe the microscopic state of things,” writes Rovelli, “then the difference between past and future vanishes … in the elementary grammar of things, there is no distinction between ’cause’ and ‘effect.'”

So, why do we perceive time as flowing forward? Rovelli notes that, although time disappears on extremely small scales, we still obviously perceive events occur sequentially in reality. In other words, we observe entropy: Order changing into disorder; an egg cracking and getting scrambled.

Rovelli says key aspects of time are described by the second law of thermodynamics, which states that heat always passes from hot to cold. This is a one-way street. For example, an ice cube melts into a hot cup of tea, never the reverse. Rovelli suggests a similar phenomenon might explain why we’re only able to perceive the past and not the future.

“Any time the future is definitely distinguishable from the past, there is something like heat involved,” Rovelli wrote for the Financial Times. “Thermodynamics traces the direction of time to something called the ‘low entropy of the past’, a still mysterious phenomenon on which discussions rage.”

He continues:

“Entropy growth orients time and permits the existence of traces of the past, and these permit the possibility of memories, which hold together our sense of identity. I suspect that what we call the “flowing” of time has to be understood by studying the structure of our brain rather than by studying physics: evolution has shaped our brain into a machine that feeds off memory in order to anticipate the future. This is what we are listening to when we listen to the passing of time. Understanding the “flowing” of time is therefore something that may pertain to neuroscience more than to fundamental physics. Searching for the explanation of the feeling of flow in physics might be a mistake.”

Scientists still have much to learn about how we perceive time, and why time operates differently depending on the scale. But what’s certain is that, outside of the realm of physics, our individual perception of time is also surprisingly elastic.

​The strange subjectivity of time

Time moves differently atop a mountain than it does on a beach. But you don’t need to travel any distance at all to experience strange distortions in your perception of time. In moments of life-or-death fear, for example, your brain would release large amounts of adrenaline, which would speed up your internal clock, causing you to perceive the outside world as moving slowly.

Another common distortion occurs when we focus our attention in particular ways.

“If you’re thinking about how time is currently passing by, the biggest factor influencing your time perception is attention,” Aaron Sackett, associate professor of marketing at the University of St. Thomas, told Gizmodo. “The more attention you give to the passage of time, the slower it tends to go. As you become distracted from time’s passing—perhaps by something interesting happening nearby, or a good daydreaming session—you’re more likely to lose track of time, giving you the feeling that it’s slipping by more quickly than before. “Time flies when you’re having fun,” they say, but really, it’s more like “time flies when you’re thinking about other things.” That’s why time will also often fly by when you’re definitely not having fun—like when you’re having a heated argument or are terrified about an upcoming presentation.”

One of the most mysterious ways people experience time-perception distortions is through psychedelic drugs. In an interview with The Guardian, Rovelli described a time he experimented with LSD.

“It was an extraordinarily strong experience that touched me also intellectually,” he said. “Among the strange phenomena was the sense of time stopping. Things were happening in my mind but the clock was not going ahead; the flow of time was not passing any more. It was a total subversion of the structure of reality.”

It seems few scientists or philosophers believe time is completely an illusion.

“What we call time is a rich, stratified concept; it has many layers,” Rovelli told Physics Today. “Some of time’s layers apply only at limited scales within limited domains. This does not make them illusions.”What is an illusion is the idea that time flows at an absolute rate. The river of time might be flowing forever forward, but it moves at different speeds, between people, and even within your own mind.

We’ll Have to Wait About 3,000 Years for a Reply From Intelligent Civilizations

#SETI #Alien #communication #ET #space #Astronomy #UFO

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As a field, the Search for Extraterrestrial Intelligence suffers from some rather significant constraints. Aside from the uncertainty involved (e.g., is there life beyond Earth we can actually communicate with?), there are the limitations imposed by technology and the very nature of space and time. For instance, scientists are forced to contend with the possibility that by the time a message is received by an intelligent species, the civilization that sent it will be long dead.

Harvard astronomers Amir Siraj and Abraham Loeb tackle this very question in a new study that recently appeared online. Taking their cue from the Copernican Principle, which states that humanity and Earth are representative of the norm (and not an outlier), they calculated that if any transmissions from Earth were heard by an extraterrestrial technological civilization (ETC), it would take about 3000 years to get a reply.

Their study, titled “Intelligent Responses to Our Technological Signals Will Not Arrive In Fewer Than Three Millennia,” recently appeared online and is being considered for publication. Whereas Siraj is a concurrent undergraduate and graduate student of astrophysics at Harvard, Prof. Loeb is the Frank B. Baird Jr. Professor of Science, the Director of Harvard’s Institute for Theory and Computation (ITC), the Chair of the Breakthrough Starshot Advisory Committee, a bestselling author, and Siraj’s academic advisor.

The globally distributed dishes of the European VLBI Network are linked with each other and the 305-m William E. Gordon Telescope at the Arecibo Observatory in Puerto Rico. Credit: Danielle Futselaar

Loeb is also renowned for theorizing that the interstellar object ‘Oumuamua, which flew past Earth in 2017, could have been extraterrestrial lightsail. This theory was originally put forth in a 2018 paper he co-wrote with postdoctoral researcher Shmuel Bialy (of the ITC). The arguments presented therein have since been expanded upon in Loeb’s most recent book, Extraterrestrial: The First Sign of Intelligent Life Beyond Earth.

Prof. Loeb recently partnered with Dr. Frank Laukien and other colleagues to launch the Galileo Project, a multinational non-profit dedicated to the study of Unidentified Aerial Phenomena (UAPs). Siraj serves as the Director of Interstellar Object Studies for this project, and he and Loeb have published extensively on subjects ranging from black holes and meteors to panspermia and interstellar objects (many of which were on the subject of ‘Oumuamua).

For the sake of this study, Siraj and Loeb focused on a particular aspect of SETI, which they dubbed the Search for Extraterrestrial Responding Intelligence (SETRI). By this, they mean ETIs that would be motivated to message Earth in response to the detection of technological activity on our planet (aka. “technosignatures”). This addresses a question of growing importance to the SETI community.

In short, does humanity have a chance of ever hearing from an ETC before our civilization collapses or is wiped out by a natural disaster? As Siraj told Universe Today via email:

“It is important to estimate the response time from extraterrestrial responding intelligences (ETRIs) since such an estimate informs the nature of effective SETI searches — as well the implications of a confirmed signal if we ever receive one. The question we try to answer in our paper is: when might we expect our first cosmic conversation to take place?”

This artist’s impression shows the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. Credit: ESO/M. Kornmesser

This establishes the first parameter of their study, which was the amount of time that humanity has been emitting detectable signatures. Of all potential technosignatures that have been considered to date, the most likely and most widely investigated by SETI researchers are still radio transmissions. In keeping with the Copernican Principle, we can assume that ETIs are also engaged in the search for signs of intelligence other than their own.

“The Copernican principle asserts that we are unlikely to live at a privileged time and so the likelihood of another habitable planet like Earth going right now through an analog of our first century of radio communication, given a few billion years of its history, is below one part in ten million,” said Loeb. “Therefore, a response is expected only within a large enough volume, containing more than ten million stars.”

It can also be safely assumed that an ETI would see radio signals as a possible technosignature and would be actively listening for them. The first long-range radio broadcast took place in 1901, when Italian inventor Guglielmo Marconi sent the first transatlantic broadcast from Cornwall, England, to St. John’s, Newfoundland. Since then, humans have been sending radio transmissions to space without thinking about the consequences.

This means that if there is a civilization within a hundred light-years of Earth with sensitive radio telescopes, they may have already heard from us. In short, we may have already “started a conversation” with an intelligent species and are just waiting for a response. Beyond this, said Siraj, they went with a number of parameters that were consistent with the Copernican Principle and the conditions under which life is known to flourish:

“[W]e considered ETIs able to communicate via electromagnetic radiation, located on Earth-like planets orbiting Sun-like stars (aka, “life as we know it”). Furthermore, we considered radio signals (which at the speed of light) as well as physical probes, which would travel slower. We used the Copernican principle, which is inherently optimistic about the prevalence of life in the Universe, to establish a lower limit on the expected response time from ETRIs.

In this illustration, NASA’s Hubble Space Telescope is looking along the paths of NASA’s Voyager 1 and 2 spacecraft as they journey through the solar system and into interstellar space. Credit: NASA/ESA/Z. Levy (STScI).

Transmission technologies can extend beyond radio waves to include other types of electromagnetic (EM) radiation, such as microwave lasers, X-rays, gamma-rays, and more. Since the only constraint is the speed of light – 299,792,458 m/s (1079 million km/h; 670.6 million mph) – it remains the fastest available option. It also means humans would only need to wait until the 22nd century for a transmission from a civilization located a hundred light-years away.

That being said, it is also possible that an ETC would choose to explore our planet more closely rather than send a transmitted reply. In this respect, Siraj and Loeb considered possibilities like the Voyager 1 and 2 missionsNew Horizonsand the Pioneer 10 and 11 spacecraft. All of these robotic missions have or will enter interstellar space (or will in the near future) and could someday be intercepted by an ETC.

It was for this reason that the Pioneer Plaques and the Golden Records were created. However, it will take millions of years before any of these missions reach even the closest star systems to Earth. This means that if a civilization sent a probe to investigate Earth in response to radio signals from a hundred years ago, it wouldn’t arrive for hundreds of thousands of years. As Loeb explained:

“Although the latter response method results in physical contact with alien objects, it requires millions of years for the journey across a hundred light-years. This means that we still have a waiting time as long as the time that has elapsed since humans first appeared on Earth before we will witness chemically-propelled crafts in response to our radio broadcasts.”

This graphic shows the relative positions of NASA’s most distant spacecraft in early 2011, looking at the solar system from the side. Credit: NASA/JPL-Caltech

Other possible concepts, like directed-energy propulsion (a la Breakthrough Starshot), could make the transit in much less time – at 20% the speed of light, it would reach Alpha Centauri in just 20 years. However, such concepts are effective for reaching the nearest star systems, but not stars 1000 light-years away within a reasonable timeline. As a final parameter, they considered just how many planets out there are likely to host an ETC.

“The Copernican principle asserts that we are unlikely to live at a privileged time and so the likelihood of another habitable planet like Earth going right now through an analog of our first century of radio communication, given a few billion years of its history, is below one part in ten million,” said Loeb. Working from this, they determined that a response could only be expected within a large enough volume, containing more than ten million stars.

Assuming that our galaxy is relatively homogenous in terms of the distribution of stars in its disk, this results in a volume of 1 billion cubic light-years (ly3) or one thousand light-years in any direction. This, in turn, entails a two-way travel time of more than two thousand years. This essentially means that if an ETC is aware of us and wants to talk, we would not be hearing from them until 4000 CE at the earliest. Or as Siraj summarized:

“We found that the fact that we have only existed as a technological civilization for about a hundred years means that, right now, we should not expect to hear back from an extraterrestrial civilization in response to our own signals. In other words, it’s extraordinarily unlikely that we could start a cosmic conversation.”

An artist’s illustration of a light-sail powered by a radio beam (red) generated on the surface of a planet. Credit: M. Weiss/CfA

This conclusion is supported by previous research (conducted with the help of Dr. Frank Drake himself!) that indicated that within various parameters, a call-and-answer scenario would take longer than the average civilization’s lifespan. In other words, any signals we receive from an ETC (whether they are a response or an attempt to “start a conversation”) are likely to have been sent by a species that has since become extinct.

This, according to Siraj, is the most significant aspect of their study, which is that civilizations have a life expectancy (which they have a measure of control over). In essence, it underscores the importance of ensuring that humanity doesn’t succumb to self-destruction or a cataclysmic fate. “The big takeaway here is that we’d better get our act together and figure out how to survive long-term if we ever want to participate in a cosmic conversation!”

How to Communicate Across the Quantum Multiverse

#quantum #multiverse #communications #manyworlds #physics

In the Many Worlds interpretation of quantum mechanics, the universal wavefunction is the reality, encompassing all possible histories and futures and all exist. But we are only sensitive to a slice of the wavefunction corresponding to our “world”, and due to the superposition principle our world can happily do its thing unperturbed by other parts of the wavefunction – other “ripples,” or worlds. And while it may seem like it would be physically impossible to have any connection between worlds, it may turn out to be entirely possible to communicate between them.

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Four ways you can see the multiverse

Every time you make a choice, you spawn a multitude of universes, leading to umpteen other yous – some of them living very different lives. This raises a myriad of moral conundrums, from what we owe our other selves to the death of hope.

It sounds like a concept from a philosopher’s fevered imagination, but many physicists believe the multiverse is real. And they’ve got evidence – here are four here are four ways that multiverse may show itself in our everyday world.

1 The wave function

This mathematical entity describes the properties of any quantum system. Such properties –– an atom’s direction of spin, say –– can take several values at once, in what is known as quantum superposition. But when we measure such a property we only get a single value: – in the case of spin, it is either up or down.

In the traditional Copenhagen interpretation of quantum mechanics, the wave function is said to “collapse” when the measurement is taken, but it isn’t clear how this happens. (Schrödinger’s famous cat, neither alive nor dead until someone looks inside its box, illustrates this.) In the multiverse, the wave function never collapses: rather, it describes the property across multiple universes. In this universe, the atom’s spin is up; in another universe, it’s down.

2 Wave-particle duality

In the landmark experiment, photons are were sent one at a time towards a pair of slits, with a phosphorescent screen behind them. Take a measurement at either slit, and you’ll register individual photons passing particle-like through one or the other. But leave the apparatus alone, and an interference pattern will build up on the screen, as if each photon had passed through both slits simultaneously and diffracted at each, like a classical wave.

This dual character has been described as the “central mystery” of quantum mechanics. In the Copenhagen interpretation, it is down to wave function collapse. Left to its own devices, each photon would pass through both slits simultaneously: the measurement at the slit forces it to “choose”. One way to explain the interference pattern through many worlds, by contrast, is that each photon only ever goes through only one slit. – Tthe pattern comes about when a photon interacts with its clone passing through the other slit in a parallel universe.

3 Quantum computing

Though quantum computers are in their infancy, they are in theory incredibly powerful, capable of solving complex problems far faster than any ordinary computer. In the Copenhagen interpretation, this is because the computer is working with entangled “qubits” which can take many more states than the binary states available to the “bits” used by classical computers. In the multiverse interpretation, it’s because it conducts the necessary calculations in many universes at once.

4 Quantum Russian roulette

This amounts to playing the role of Schrödinger’s cat. You’ll need a gun whose firing is controlled by a quantum property, such as an atom’s spin, which has two possible states when measured. If the Copenhagen interpretation is right, you have the familiar 50-50 odds of survival. The more times you “play”, the less likely you are to survive.

New Scientist Default Image

If the multiverse is real, on the other hand, there always will be a universe in which “you” are alive, no matter how long you play. What’s more, you might always end up in it, thanks to the exalted status of the “observer” in quantum mechanics. You would just hear a series of clicks as the gun failed to fire every time – and realise you’re immortal. But be warned: even if you can get hold of a quantum gun, physicists have long argued about how this most decisive of experiments would actually work out.