A week after astronomers noticed a new object in the sky, they’ve identified it as a comet.
A new visitor is swinging by the solar system: a never-before-observed comet that hails from the Oort Cloud.
This alien object was just designated as a comet Wednesday (June 23), only a week after astronomers first observed it as a tiny, moving dot in archival images from the Dark Energy Camera at the Cerro Tololo Inter-American Observatory in Chile. The comet is now known as Comet C/2014 UN271, or Bernardinelli-Bernstein after its discoverers, University of Pennsylvania graduate student Pedro Bernardinelli and astronomer Gary Bernstein.
The comet, which may be an impressive 62 miles (100 kilometers) wide, is 20 times the distance from Earth to the sun away, heading toward our blue dot. It will reach its closest point to the sun in its orbit on Jan. 23, 2031, when it will be just beyond the orbit of Saturn, or about 10.95 times the distance between Earth and the sun.
“We will have practically 20 years to study it,” said Peter Vereš, an astronomer at the Center for Astrophysics Harvard & Smithsonian and at the Minor Planet Center, which identifies and computes orbits for new comets, minor planets and other far-flung rocky bodies. That’s an exciting opportunity, he said, because the comet is likely a near-pristine object from the Oort Cloud, a field of icy, rocky debris that likely surrounds the solar system like a crunchy shell.
Unidentified orbiting object
Comet Bernardinelli-Bernstein first made its appearance in the 2014 archives of the Dark Energy Camera. Bernardinelli and Bernstein soon realized that the object, which looked like nothing more than a dot, was moving over time as they traced it through 2015, 2016, 2017 and 2018.
The astronomers sent the observation to the Minor Planet Center, which at first classified the object as an asteroid or minor planet, since its surface appeared to be chemically inert. The report of the new object triggered amateur astronomers to point their telescopes skyward, though, and some soon noticed a “coma,” or haze of vapors and dust, emanating from the object.
“They found out, ‘Oh look, this object is active,'” Vereš told Live Science.
Comets are active because the sun’s heat and solar wind cause gas to release from the surface. It’s likely that the surface has become more active over the past few years as the comet streaked closer to the sun, Vereš said, making the activity easier to spot.
A long journey
The comet takes approximately 5.5 million years to complete its orbit, which is vertical to the plane of the planets, Minor Planet Center researchers have calculated. At its farthest point away, it’s approximately a light-year from the sun. Based on its orbit, the comet is likely an emissary from a far-off, ice-cold region past the outer edges of the solar system known as the Oort Cloud. Objects like the Bernardinelli-Bernstein comet were probably once part of the solar system, Vereš said, but they were kicked out by gravitational interactions with large planets like Saturn and Neptune.
Though the comet’s history isn’t certain, this newfound trek may be its first foray back into the solar system since its initial banishment, Vereš said. That’s exciting, because the short-periodicity comets that circle within the solar system are significantly altered from their original form, baked and diminished by many rotations around the sun. Long-periodicity comets like Bernardinelli-Bernstein that stay in the outer parts of the solar system don’t change as much, meaning they’re a time capsule of conditions at their formation in the early days of the solar system.
“We are receiving more and more observations basically every day,” Vereš said. To the eye, the comet still looks like a fuzzy dot and probably won’t ever be visually impressive, he said; but sensitive instruments on large telescopes may soon be able to detect variations in the light coming from the comet that can reveal the molecules coming off its surface. These data could reveal what the comet is made of.
An international team of scientists led by a prominent Harvard astronomer announced a new initiative Monday to look for evidence of technology built by extraterrestrial civilizations.
Called the Galileo Project, it envisages the creation of a global network of medium-sized telescopes, cameras and computers to investigate unidentified flying objects, and has so far been funded with $1.75 million from private donors.
Given recent research showing the prevalence of Earth-like planets throughout the galaxy, “We can no longer ignore the possibility that technological civilizations predated us,” Professor Avi Loeb told reporters at a news conference.
“The impact of any discovery of extraterrestrial technology on science, our technology, and on our entire world view, would be enormous,” he added in a statement.
The project includes researchers from Harvard, Princeton, Cambridge, Caltech and the University of Stockholm.
It was announced a month after the Pentagon released a report about unidentified aerial phenomena, which stated that their nature was unclear.
“What we see in our sky is not something that politicians or military personnel should interpret, because they were not trained as scientists, it’s for the science community to figure out,” said Loeb, adding that he hoped to increase the project’s funding tenfold.
Apart from studying UFOs, the Galileo Project wants to investigate objects that visit our solar system from interstellar space, and searching for alien satellites that might be probing Earth.
Loeb refers to such research as a new branch of astronomy he calls “space archaeology,” intended to complement the existing field of the Search for Extraterrestrial Intelligence (SETI), which mainly probes for alien radio signals.
These endeavors will require collaborations with existing and future astronomical surveys, including from the Vera C. Rubin Observatory in Chile that is due to go online in 2023 and is eagerly awaited by the scientific community.
The 59-year-old Israeli-American has published hundreds of pioneering papers and collaborated with the late Stephen Hawking, but created controversy when he suggested an interstellar object that briefly visited our system in 2017 could have been an alien probe sailing on solar winds.
He laid out his arguments in scientific papers and the book “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth,” which placed him at odds with many in the astronomy community.
The new project is accordingly named after Italian astronomer Galileo Galilei, who was punished when he provided key evidence for the Earth not being at the center of the universe.
The project’s co-founder Frank Laukien, a visiting scholar at Harvard’s chemistry and chemical biology department, declared himself the “resident skeptic.”
But he said that, rather than dismissing the ideas outright, it was necessary to “agnostically record and interpret the data according to the scientific method.”
“Stealth” solar storms are difficult to detect before they are near Earth.
The use of various imaging techniques from multiple angles allowed researchers to detect these stealth storms earlier than ever.
Not seeing one coming could have disastrous effects on our electronic infrastructure.
Solar storms are a collection of disturbances on the sun that influence space weather. They include things like solar flares and coronal mass ejections (CMEs), a large release of plasma in the solar wind. They can affect Earth in a number of ways, such as by increasing the number of particles that hit the Earth’s magnetic field causing an aurora or — in severe cases — by disrupting technology and radio transmissions.
Most of the time, scientists can see storms as they occur on the sun. Information about the impact on Earth can be gathered a few days before it is likely to reach us. However, in as many as 20 percent of CMEs, there is little to no noticeable activity on the sun to give us an early warning. These “stealth” CMEs can have a huge impact on space weather but have proven difficult to spot until they have nearly arrived.
Unlike regular CMEs, stealth CMEs do not tend to give typical warning signs like clear dimming or brightening of the surface of the sun. Instead, they seem to form in a higher region of the sun’s atmosphere called the corona than is typical. Unfortunately, watching for changes in the corona does not always give scientists the information they need to predict where a mass of plasma is moving.
In this study, the researchers took advantage of knowing the approximate origins of four stealth CMEs that were determined by data collected from Earth and the STEREO satellite, which was at a different angle with respect to the sun. The four CMEs differed in angle and intensity and occurred at different points in the solar cycle.
By using different imaging processes, subtle shifts in the upper corona were identified in each of the four cases examined. Most of the events also originated near areas with particularly strong magnetic fields.
The authors suggest that the small brightening and dimming effects they observed could be used to detect these CMEs in the future using similar methods. While they admit that the study does not provide a way to detect these CMEs before they form, they conclude that “identifying the source region of a stealth CME represents a first step toward providing more reliable predictions.”
A bad day for Earth
Solar storms are not merely of academic interest. Large storms have occurred before, and the damage they can cause is potentially devastating. A strong solar storm in1989 caused blackouts in Quebec and disrupted broadcasts of Radio Free Europe. That storm has nothing on the “Carrington Event” of 1859, however.
That solar storm was incredibly powerful, producing auroras visible in places like Queensland, Australia and the Caribbean. The auroras over New England were so bright that the residents could read newspapers by their light. Telegraph systems fried as a result of the huge amount of electromagnetic energy added to the Earth’s magnetosphere, occasionally starting fires as they spontaneously sparked. Some telegraph operators reported being able to operate their machines without connecting them to wires.
A storm estimated to be just as powerful as the Carrington Event occurred in 2012, but the plasma it ejected narrowly missed Earth. According to a study by the National Academy of Sciences, the total cost of such an event to the United States today could be more than two trilliondollars. It would also cause damage that could take years to fully repair. It goes without saying that having large portions of our electric systems and technology fried with little time to prepare might also make things unpleasant for a lot of people.
Smaller storms hit Earth once every three years, often causing damage to systems that use electricity. Larger events are rarer, but not as rare as we would hope. A study from a few years ago calculated that the odds of a Carrington level event occurring is 12 percent per decade.
May the odds be in our favor
With odds and consequences like that, the ability to see a “stealth” solar storm coming might prove to be one of the most important tools humanity ever discovered.
Given enough warning, precautions can be taken to help minimize the damage to electronics from a large solar storm. For example, satellites can be moved out of harm’s way, power grids can be primed to avoid being overloaded, and transformers can be taken offline to keep them from being destroyed.
If we fail to see the next Carrington Event coming, it might be a while before you can read the article we’ll write about it.
From a “butt crack rock” to a cannonball, entertaining images from Mars amuse scientists and excite conspiracy theorists and alien fans.
#Mars #Space #Solarsystem #Weird #Astronomy
Face on Mars is a classic
Humans love a good space story. That’s why it’s so much fun to speculate about unusual objects seen in images of Mars. Our imaginations turn rock formations into fish and cosmic rays into alien communications. A recent image from the NASA Perseverance rover generated plenty of jokes about what looks like a rear end. Is it an alien keister? Nope. It’s just a goofy rock formation.
Join us as we explore some famous Mars mysteries and the scientific explanations behind them.
NASA’s Viking 1 Orbiter zipped near Mars in 1976 and took this now iconic image of the surface. What got everyone excited is the face-like formation in the upper center of the picture. If you have a creative mind, it’s easy to see it as having two eyes, a nose, a mouth and a weird hairdo. It even looks a bit like a young Elvis Presley. You can see why some people thought the face was an alien-built monument on Mars.
2 of 57NASA
A newer look at the Mars face
NASA wasn’t going to let the face on Mars go without an explanation. The Mars Global Surveyor cleared things up for good in 2001 by taking a fresh image of the face. The newer, sharper, higher-resolution picture shows a much blobbier, less stark formation. In short, it’s just a mesa and not an alien-carved religious site.READ MORE
3 of 57NASA/JPL-Caltech/ASU
Perseverance rover ‘Butt crack rock’
NASA’s Perseverance rover arrived on the red planet in February 2021 and has since snapped a bounty of images of the landscape in the Jezero Crater. This fantastically funny-looking rock caught the eye of space fans who laughed about its resemblance to a rear end. It earned the nickname “butt crack rock.”READ MORE
4 of 57ESA/DLR/FU Berlin
Mars south pole ‘angel’ and ‘heart’
Apply a little imagination to this European Space Agency Mars Express view of the red planet’s south pole and you’ll see an angel and a heart together. ESA described it as an “angelic figure” in a December 2020 image release.
It’s simply a bit of geology on display from the icy polar region where an impact crater forms the “head” and halo, and a sublimation pit (a spot where the ice turned to vapor) formed the “hand” on the left.READ MORE
5 of 57NASA/JPL-Caltech/MSSS
Mother of pearl clouds
Yes, these shimmering, colorful clouds appeared on Mars. NASA’s Curiosity rover doesn’t just eye the local geology; it also documents what’s happening in the sky. This view of iridescent “mother of pearl” clouds comes from March 5, 2021.
“If you see a cloud with a shimmery pastel set of colors in it, that’s because the cloud particles are all nearly identical in size,” said atmospheric scientist Mark Lemmon with the Space Science Institute in Colorado. “That’s usually happening just after the clouds have formed and have all grown at the same rate.” READ MORE
6 of 57NASA/JPL-Caltech/LANL/Red circle by Amanda Kooser/CNET
Software engineer and citizen scientists Kevin Gill has a knack for finding funny Mars rocks in rover images. He spotted this brachiosaurus-shaped rock as snapped by the Perseverance rover on Mars in April 2021. Unfortunately, we’ve seen no evidence of real dinosaurs on Mars, and we’re still looking for signs of ancient microbial life. READ MORE
8 of 57NASA/JPL/University of Arizona
The HiRise camera team for NASA’s Mars Reconnaissance Orbiter spacecraft spotted a Planters Mr. Peanut mascot lookalike in this collection of pits on Mars. “The south polar residual cap is constantly changing as carbon dioxide sublimates from steep slopes, enlarging pits, and condenses on flat areas, filling pits,” wrote planetary geologist Alfred McEwen in a HiRise statement in May 2021.
I think this looks like Mr. Peanut spawning Baby Nut, which is even weirder than if it was just Mr. Peanut alone.READ MORE
9 of 57NASA/JPL-Caltech/MSSS/Red circle by Amanda Kooser/CNET
Robot leg or rock? It’s a rock
Not a boot. Not a bot. This tiny rock on Mars captured attention in early 2019 thanks to its resemblance to a boot or a robot leg. It’s neither of those things, but it is a fun shape. The images comes from NASA’s Curiosity rover.READ MORE
10 of 57NASA/JPL/UArizona
HiRise dust devil tracks
NASA’s Mars Reconnaissance Orbiter caught sight of some wild dust devils tracks on Mars in late 2018. They look like claw marks, and they pop out thanks to the image processing done on this view from the spacecraft’s HiRise camera. Mars is a very windy place and dust devils are common.READ MORE
11 of 57NASA/JPL-Caltech
If this looks like it was made by humans, it’s because it was. NASA’s Perseverance rover landed on Mars in February 2021 and it left some debris behind on the ground when it dropped an ejectable belly pan on purpose. The pan acted as a protective cover for the rover’s sampling system, which will allow it to collect and cache rock samples for a later mission to come pick up. After landing, the cover was no longer needed.READ MORE
12 of 57NASA/JPL-Caltech/ASU
Perseverance sees a rock
NASA’s Perseverance rover snapped a view of this odd rock on March 2021. If you look closely just to the right of center, you can see a series of tiny marks where the rover’s laser zapped it. This was the first celebrity rock of the rover’s expedition as scientists and space fans questioned if was a weathered piece of bedrock, a chunk or Mars thrown from somewhere else by an impact event, or possibly a meteorite.READ MORE
13 of 57NASA/JPL/UArizona
Happy Face Crater
NASA’s Mars Reconnaissance Orbiter viewed the “Happy Face Crater” on Mars in both 2011 and 2020 and found some changes in its complexion. You can see how it got its nickname. The crater is located in the south pole region and the difference in darkness of the features is due to the changing frost cover on the ground.READ MORE
14 of 57NASA/JPL-Caltech/Red circle by Amanda Kooser/CNET
Dark, shiny boulder
NASA’s Curiosity rover snapped this view of a dark, shiny boulder on Mars on Dec. 6, 2020. The overall view is lovely, but the boulder was a bit of a mystery for how it stood out against the surrounding landscape. It’s possible the boulder could be a meteorite or was perhaps deposited there from elsewhere on Mars.READ MORE
This is exactly what my misshapen pancakes look like on Sunday mornings. NASA’s Curiosity rover snapped this shiny, flattish rock in November 2020, leading space fans to compare it with various food items, including pancakes and melted chocolate ice cream. The rock may have been polished to a sheen thanks to wind and sand action.READ MORE
17 of 57NASA/JPL-Caltech/MSSS
Oh look, a thigh bone on Mars
Mark one up for the funny-bone file. NASA’s Curiosity rover sent a photo back to Earth in 2014 that showed a very odd rock shaped a bit like a femur bone from a human thigh. Scientists obligingly explained that the unusual shape was most likely the product of erosion by wind or water. If NASA ever did amazingly find human remains on Mars, scientists would want to shout it from the rooftops.READ MORE
18 of 57NASA/JPL/University of Arizona
This view from NASA’s Mars Reconnaissance Orbiter, snapped in February 2016, shows some strange formations on the surface of the red planet. The dark, raised areas are a series of dunes that look a lot like the dots and dashes of Morse code.
Unfortunately, the code spells out gibberish. Planetary scientist Veronica Bray analyzed the dune image and told Gizmodo the code works out to read “NEE NED ZB 6TNN DEIBEDH SIEFI EBEEE SSIEI ESEE SEEE !!”
Automatic machine learning is a fast-developing branch of deep learning.
It seeks to vastly reduce the amount of human input and energy needed to apply machine learning to real-world problems.
AutoML-Zero, developed by scientists at Google, serves as a simple proof-of-concept that shows how this kind of technology might someday be scaled up and applied to more complex problems.
Machine learning has fundamentally changed how we engage with technology. Today, it’s able to curate social media feeds, recognize complex images, drive cars down the interstate, and even diagnose medical conditions, to name a few tasks.
But while machine learning technology can do some things automatically, it still requires a lot of input from human engineers to set it up, and point it in the right direction. Inevitably, that means human biases and limitations are baked into the technology.
So, what if scientists could minimize their influence on the process by creating a system that generates its own machine-learning algorithms? Could it discover new solutions that humans never considered?
To answer these questions, a team of computer scientists at Google developed a project called AutoML-Zero, which is described in a preprint paper published on arXiv.
“Human-designed components bias the search results in favor of human-designed algorithms, possibly reducing the innovation potential of AutoML,” the paper states. “Innovation is also limited by having fewer options: you cannot discover what you cannot search for.”
Automatic machine learning (AutoML) is a fast-growing area of deep learning. In simple terms, AutoML seeks to automate the end-to-end process of applying machine learning to real-world problems. Unlike other machine-learning techniques, AutoML requires relatively little human effort, which means companies might soon be able to utilize it without having to hire a team of data scientists.
AutoML-Zero is unique because it uses simple mathematical concepts to generate algorithms “from scratch,” as the paper states. Then, it selects the best ones, and mutates them through a process that’s similar to Darwinian evolution.
AutoML-Zero first randomly generates 100 candidate algorithms, each of which then performs a task, like recognizing an image. The performance of these algorithms is compared to hand-designed algorithms. AutoML-Zero then selects the top-performing algorithm to be the “parent.”
“This parent is then copied and mutated to produce a child algorithm that is added to the population, while the oldest algorithm in the population is removed,” the paper states.
The system can create thousands of populations at once, which are mutated through random procedures. Over enough cycles, these self-generated algorithms get better at performing tasks.
“The nice thing about this kind of AI is that it can be left to its own devices without any pre-defined parameters, and is able to plug away 24/7 working on developing new algorithms,” Ray Walsh, a computer expert and digital researcher at ProPrivacy, told Newsweek.
If computer scientists can scale up this kind of automated machine-learning to complete more complex tasks, it could usher in a new era of machine learning where systems are designed by machines instead of humans. This would likely make it much cheaper to reap the benefits of deep learning, while also leading to novel solutions to real-world problems.
Still, the recent paper was a small-scale proof of concept, and the researchers note that much more research is needed.
“Starting from empty component functions and using only basic mathematical operations, we evolved linear regressors, neural networks, gradient descent… multiplicative interactions. These results are promising, but there is still much work to be done,” the scientists’ preprint paper noted.
A quantum experiment suggests there’s no such thing as objective reality
#Reality #quantum #experiment #science #physics
Physicists have long suspected that quantum mechanics allows two observers to experience different, conflicting realities. Now they’ve performed the first experiment that proves it.by
IBM RESEARCH | FLICKR
Back in 1961, the Nobel Prize–winning physicist Eugene Wigner outlined a thought experiment that demonstrated one of the lesser-known paradoxes of quantum mechanics. The experiment shows how the strange nature of the universe allows two observers—say, Wigner and Wigner’s friend—to experience different realities.
Since then, physicists have used the “Wigner’s Friend” thought experiment to explore the nature of measurement and to argue over whether objective facts can exist. That’s important because scientists carry out experiments to establish objective facts. But if they experience different realities, the argument goes, how can they agree on what these facts might be?
That’s provided some entertaining fodder for after-dinner conversation, but Wigner’s thought experiment has never been more than that—just a thought experiment.
Last year, however, physicists noticed that recent advances in quantum technologies have made it possible to reproduce the Wigner’s Friend test in a real experiment. In other words, it ought to be possible to create different realities and compare them in the lab to find out whether they can be reconciled.
And today, Massimiliano Proietti at Heriot-Watt University in Edinburgh and a few colleagues say they have performed this experiment for the first time: they have created different realities and compared them. Their conclusion is that Wigner was correct—these realities can be made irreconcilable so that it is impossible to agree on objective facts about an experiment.
Wigner’s original thought experiment is straightforward in principle. It begins with a single polarized photon that, when measured, can have either a horizontal polarization or a vertical polarization. But before the measurement, according to the laws of quantum mechanics, the photon exists in both polarization states at the same time—a so-called superposition.
Wigner imagined a friend in a different lab measuring the state of this photon and storing the result, while Wigner observed from afar. Wigner has no information about his friend’s measurement and so is forced to assume that the photon and the measurement of it are in a superposition of all possible outcomes of the experiment.
Wigner can even perform an experiment to determine whether this superposition exists or not. This is a kind of interference experiment showing that the photon and the measurement are indeed in a superposition.
From Wigner’s point of view, this is a “fact”—the superposition exists. And this fact suggests that a measurement cannot have taken place.
But this is in stark contrast to the point of view of the friend, who has indeed measured the photon’s polarization and recorded it. The friend can even call Wigner and say the measurement has been done (provided the outcome is not revealed).
So the two realities are at odds with each other. “This calls into question the objective status of the facts established by the two observers,” say Proietti and co.
That’s the theory, but last year Caslav Brukner, at the University of Vienna in Austria, came up with a way to re-create the Wigner’s Friend experiment in the lab by means of techniques involving the entanglement of many particles at the same time.
The breakthrough that Proietti and co have made is to carry this out. “In a state-of-the-art 6-photon experiment, we realize this extended Wigner’s friend scenario,” they say.
They use these six entangled photons to create two alternate realities—one representing Wigner and one representing Wigner’s friend. Wigner’s friend measures the polarization of a photon and stores the result. Wigner then performs an interference measurement to determine if the measurement and the photon are in a superposition.
The experiment produces an unambiguous result. It turns out that both realities can coexist even though they produce irreconcilable outcomes, just as Wigner predicted.
That raises some fascinating questions that are forcing physicists to reconsider the nature of reality.
The idea that observers can ultimately reconcile their measurements of some kind of fundamental reality is based on several assumptions. The first is that universal facts actually exist and that observers can agree on them.
But there are other assumptions too. One is that observers have the freedom to make whatever observations they want. And another is that the choices one observer makes do not influence the choices other observers make—an assumption that physicists call locality.
If there is an objective reality that everyone can agree on, then these assumptions all hold.
But Proietti and co’s result suggests that objective reality does not exist. In other words, the experiment suggests that one or more of the assumptions—the idea that there is a reality we can agree on, the idea that we have freedom of choice, or the idea of locality—must be wrong.
Of course, there is another way out for those hanging on to the conventional view of reality. This is that there is some other loophole that the experimenters have overlooked. Indeed, physicists have tried to close loopholes in similar experiments for years, although they concede that it may never be possible to close them all.
Nevertheless, the work has important implications for the work of scientists. “The scientific method relies on facts, established through repeated measurements and agreed upon universally, independently of who observed them,” say Proietti and co. And yet in the same paper, they undermine this idea, perhaps fatally.
The next step is to go further: to construct experiments creating increasingly bizarre alternate realities that cannot be reconciled. Where this will take us is anybody’s guess. But Wigner, and his friend, would surely not be surprised.
As per the National Oceanic and Atmospheric Administration (NOAA), a dense stream of solar wind enveloped the Earth late on 14 July, but no notable impact was observed as the phenomenon wasn’t particularly powerful on the space weather scale.
The American agency confirmed that the phenomenon lasted for a few hours and slightly unsettled the Earth’s magnetic field.
The solar storm passed through the planet at 16:41 UTC (22:11 IST) with a geomagnetic K-index of 4. The K-index is used to characterise the magnitude of geomagnetic storms, and a level of 4 indicates minor disturbance, as per the NOAA alert.
The US agency stated that weak power grid fluctuations happened due to the solar storm, and expected auroras to be visible at high latitudes such as Canada and Alaska. However, the local US media has not reported any such sightings.
All about the solar storm
The massive solar storm, which moved towards the Earth at a speed of 1.6 million kilometres per hour, was supposed to hit the Earth last week, following which a power failure around the globe was expected, according to spaceweather.com.
“THE SOLAR WIND IS COMING: Later today, a high-speed stream of solar wind is expected to hit Earth’s magnetic field. Flowing from an equatorial hole in the sun’s atmosphere, wind speeds could top 500 km/s. Full-fledged geomagnetic storms are unlikely, but lesser geomagnetic unrest could spark high latitude auroras,” the spaceweather.com said.
The National Oceanic and Atmospheric Administration has reportedly classified the solar storm as G-1 or ‘minor’.
What are geomagnetic storms?
A major disturbance of Earth’s magnetosphere, which occurs when there is a very efficient exchange of energy from the solar wind into the space environment surrounding Earth, is known as a geomagnetic storm. The storm is the result of major changes in the currents, plasmas produced by solar winds, as per the NOAA.
The most powerful geomagnetic storm ever recorded resulted in the 1859 Carrington Event, when telegraph lines electrified, zapping operators and setting offices ablaze in North America and Europe.
To create a geomagnetic storm, a solar wind has to sustain high speeds for a long period of time, which transfers the energy of the wind into Earth’s magnetic field.
The fierce and largest storms that result from these situations are associated with solar Coronal Mass Ejections (CMEs) where billions of tons of plasma from the Sun are hurtled towards planets that also reach Earth. While coronal mass ejections take days to arrive at Earth, some have been observed to arrive within 15-18 hours of being ejected from the Sun.
Deep in the heart of South Texas, Elon Musk’s SpaceX is hard at work creating the next generation of space travel. Called Starship, their top-of-the-line, one-of-a-kind spaceship is unlike any other that has come before it. It will be 30 feet in diameter, 180 feet tall and powered by the trademarked Super Heavy launch vehicle, which will propel Starship into space with the assistance of 31 Raptor engines. With the Starship and the Super Heavy combined, the craft will be the tallest, heaviest and most powerful space rocket that has ever graced the stars.
But the creation is more than just a record-breaker. Perhaps the most amazing thing about Starship will be the fact that it’s totally reusable unlike the spaceships of yesteryear created by NASA. The ability to reuse this ship is really what sets it apart and will make it much more financially enticing for SpaceX and any other space agencies.
To call Starship a modern marvel of engineering would be an understatement. It really does set the bar high for the future of flying through space. Generations of spaceships and prototypes have all led up to this creation.
And yet, Elon Musk isn’t satisfied with Starship. Even though his company is producing something revolutionary and ahead-of-its-time, Musk is already looking ahead to the next iteration of Starship. In fact, he has recently hinted at the concept of an even bigger Starship model, as well as special variants of the ship that would be capable of point-to-point travel on Earth, cargo shipments, and trips to the moon and Mars.
Can aliens explain both the origin of life and the fine tuning?
Aliens are in the news again. In June, a Navy report could not rule out the possibility that “unexplained aerial phenomena” spotted in our atmosphere were visitors from outer space. In January, Harvard astronomer Avi Loeb claimed an alien spacecraft had actually swept through our solar system in 2017 — and more are coming. Loeb later doubled down, suggesting that UFOs spotted by the military could be spies sent to gather intelligence about our life on Earth.
As crazy as it all sounds, scientists have long posited the possibility of aliens on our planet. In fact, Francis Crick (who along with James Watson won the Nobel Prize for discovering the structure of the DNA molecule) once theorized that life on Earth was “deliberately transmitted” by intelligent extra terrestrials. Far from being scorned, Crick’s “Directed panspermia” theory was presented at a conference organized by Carl Sagan in 1971 and later published as a scientific paper.
Scientists took this idea seriously because even the simplest living cells aren’t simple at all.
Watson and Crick discovered that chemical subunits in DNA function like letters in a written language or digital symbols in computer code. As Bill Gates explains, “DNA is like a computer program, but far, far more advanced than any software we’ve ever created.”
Evolutionary biologist Richard Dawkins echoes this assessment, noting the “machine code of the genes is uncannily computer-like.” In a recent tweet, he confessed to being knocked “sideways with wonder at the miniaturized intricacy of the data-processing machinery in the living cell.”
The presence of information in even the simplest living cells suggests that intelligent design played a role in life’s origin. After all, we know computer programs come from programmers and information generally — in a book or newspaper, for example — always arises from an intelligent source.
Perhaps for this reason, Dawkins once acknowledged the cell might contain a “signature of intelligence” — and attributed the source of that intelligence to alien intervention. As he mused, “it could be that somewhere in the universe, a civilization evolved . . . [a] high level of technology and designed a form of life that they seeded onto this planet.”
But invoking an alien intelligence as the source of life on Earth does nothing to explain how life, and the information needed to produce it, first arose elsewhere. “Panspermia” just kicks that ultimate question out into space.
In addition, no alien being within the universe can explain what scientists have discovered about the structure of the universe.
Since the 1960s, physicists have learned that we live in a “Goldilocks universe” where the fundamental parameters of physics have been finely tuned, against all odds, to make life possible. Even slight alterations in the values of key factors — such as the strength of gravity or electromagnetism or the masses of elementary particles — would render life impossible.
Consequently, many scientists think this fine tuning points to a cosmic fine-tuner or “super-intellect” as Cambridge astrophysicist Sir Fred Hoyle famously put it. Moreover, the fine-tuning parameters were set at, or soon after, the beginning of the universe, long before any alien intelligence could have evolved or acted to determine them.
Can aliens explain both the origin of life and the fine tuning? Probably not. Explaining both these mysteries requires an intelligence who can act within the universe (to produce the code necessary to life) and also act on the universe as a whole from the beginning (to establish its finely-tuned structure).
Believers in this kind of intelligence greatly outnumber believers in alien astronauts. They have long called this intelligence behind life and the universe by a different name.
A Major X Class Solar Flare Just Slammed Into Earth
The strongest solar flare seen in four years erupted from the surface of the sun early Saturday and smacked into our planet’s atmosphere eight minutes later.
An explosion from a new and unnamed sunspot produced the X-class flare, the first of solar cycle 25.
The blast of x-rays traveled toward earth at the speed of light, colliding with the top of our atmosphere and causing a shortwave radio blackout over the Atlantic ocean and coastal regions. The below blackout map shows where radio operators may have noticed the weirdness around 10:30 a.m. ET
Astronomer and space weather watcher Dr. Tony Phillips says the sunspot that produced the X1.59 flare appeared suddenly, like a cloudless day that quickly turns stormy.
“Yesterday it did not even exist, highlighting the unpredictability of solar activity,” Phillips writes at Spaceweather.com. “More flares may be in the offing, so stay tuned.”
There appears to be little risk of an accompanying coronal mass ejection (CME) with this flare. A CME is a burst of hot, charged plasma that often occurs alongside a flare. The particles from a CME can take a few days to reach earth and cause additional interference with radio and electrical systems when they arrive.
Fortunately, the sunspot that produced this flare was on the edge of the sun’s face, making it unlikely that a CME would be directed towards Earth.
Solar flares are classified by their X-ray brightness as A, B, C, M or X with A being the smallest and X being the brightest and largest. This was the first X flare tossed off by the sun since a new solar cycle began in December 2019.
The sun undergoes an approximately 11-year-long activity cycle in which it swells to a peak at the middle of the cycle and then begins to quiet down until the end of the cycle when it all repeats.
While this is the first major flare of the young solar cycle, it measured just a X1.59, when the last solar cycle gave us a far more powerful X9 flare in 2017. All this means it’s worth heeding Phillips’ warning that stronger flares are likely on the way in the coming months.
In the past strong flares and CMEs have produced widespread power outages and communications blackouts. There is some concern that we are overdue for a catastrophic solar storm which could do unprecedented damage to power grids on the ground and the record number of satellites now in orbit, potentially crippling systems on the ground that rely on satellite communications.
Solar Flares: What Does It Take to Be X-Class?
Solar flares are giant explosions on the sun that send energy, light and high speed particles into space. These flares are often associated with solar magnetic storms known as coronal mass ejections (CMEs). The number of solar flares increases approximately every 11 years, and the sun is currently moving towards another solar maximum, likely in 2013. That means more flares will be coming, some small and some big enough to send their radiation all the way to Earth.
The biggest flares are known as “X-class flares” based on a classification system that divides solar flares according to their strength. The smallest ones are A-class (near background levels), followed by B, C, M and X. Similar to the Richter scale for earthquakes, each letter represents a 10-fold increase in energy output. So an X is ten times an M and 100 times a C. Within each letter class there is a finer scale from 1 to 9.
The Solar and Heliospheric Observatory (SOHO) spacecraft captured this image of a solar flare as it erupted from the sun early on Tuesday, October 28, 2003.Image Credit: ESA & NASA/SOHO› View larger
The Halloween solar storms of 2003 resulted in this aurora visible in Mt. Airy, Maryland.Image Credit: NASA/George Varros› View larger
C-class and smaller flares are too weak to noticeably affect Earth. M-class flares can cause brief radio blackouts at the poles and minor radiation storms that might endanger astronauts.
And then come the X-class flares. Although X is the last letter, there are flares more than 10 times the power of an X1, so X-class flares can go higher than 9. The most powerful flare measured with modern methods was in 2003, during the last solar maximum, and it was so powerful that it overloaded the sensors measuring it. The sensors cut out at X28.
The biggest X-class flares are by far the largest explosions in the solar system and are awesome to watch. Loops tens of times the size of Earth leap up off the sun’s surface when the sun’s magnetic fields cross over each other and reconnect. In the biggest events, this reconnection process can produce as much energy as a billion hydrogen bombs.
If they’re directed at Earth, such flares and associated CMEs can create long lasting radiation storms that can harm satellites, communications systems, and even ground-based technologies and power grids. X-class flares on December 5 and December 6, 2006, for example, triggered a CME that interfered with GPS signals being sent to ground-based receivers.
NASA and NOAA – as well as the US Air Force Weather Agency (AFWA) and others — keep a constant watch on the sun to monitor for X-class flares and their associated magnetic storms. With advance warning many satellites and spacecraft can be protected from the worst effects.
An international scientific team led by Antonin Affholder from the University of Paris in France wanted to know whether the gases emanating from Saturn’s moon Enceladus are likely of chemical or biological origin. During close fly-bys of the moon ending in 2015, the Cassini spacecraft detected hydrogen and methane, among other gases, which implied the presence of hydrothermal activity in the liquid water ocean beneath Enceladus’s icy surface. Could these be analogous to hydrothermal vents like the “black smokers” on Earth, which are a haven for biology? Microbes living at these vents produce methane (and water) from hydrogen and carbon dioxide gas as part of their natural metabolic reactions.
The science team used a method known as Bayesian statistics, where probability is expressed as a degree of belief based on prior obtained data and insights. They took mathematical models of known geophysical, geochemical, and biological processes, and included them in their statistical approach to quantify the plausibility of different hypotheses about Enceladus.
Methane can be an indicator of biology, but it can also form through an abiotic reaction that most commonly occurs in Earth’s oceanic crust, called serpentinization, which produces methane when water reacts with certain rock types.
Affholder’s results showed that the methane concentrations measured in Enceladus’s gaseous plume are too high to be solely due to serpentinization. In fact, they concluded that the likeliest explanation is biology. Otherwise, to explain the high methane levels, an unknown abiotic process would have to be invoked.
This reminds me of the controversy over phosphine at Venus, which also was presented as being explainable only by biology or an unknown chemical process. While the detection of methane and hydrogen in the Enceladus plume is undebatable (contrary to the phosphine detection at Venus), this study is still inconclusive, since we aren’t certain whether life is even possible inside Enceladus.
The moon’s ice-covered ocean may well be habitable now (I actually expect that), but if life requires Darwin’s “little pond” on a solid planetary surface to arise in the first place, it would not have developed on Enceladus. In general, environmental constraints for the origin of life are likely much more restrictive then for its presence. In other words, there may be many uninhabited habitable places in the galaxy.
As long as we haven’t resolved this central question, I’m not certain whether statistical analyses like Affholder’s will really move us forward. But the question of life beneath the icy surface of Enceladus needs to be investigated. Any anomaly that we can’t readily explain needs to be looked at more closely. We might even have a stroke of luck. Let’s say the authors are correct about methanogenesis. If a follow-up mission to Saturn detects biology on Enceladus, it would tell us that hydrothermal vents are one place that life can originate.
Is there a connection between ‘Oumuamua and Unidentified Aerial Phenomena?
#space #oumuamua #UAP #UFO #extraterrestrial
If some UAP turn out to be extraterrestrial technology, they could be dropping sensors for a subsequent craft to tune into. What if ‘Oumuamua is such a craft?
A colleague of mine once noted that every morning there is a long line of customers stretching out from a famous Parisian bakery into the street. “I wish someone would wait for my scientific papers with as much anticipation as Parisians eagerly stand by for their baguettes,” he said.
There is one exception to this wish, however. It involves fresh scientific evidence that we are not be the only intelligent species in the cosmos.
Recently, there have been two sources for such evidence.
First, the interstellar object discovered in 2017, ‘Oumuamua, was inferred to have a flat shape and seemed to be pushed away from the sun as if it were a lightsail. This “pancake” was tumbling once every eight hours and originated from the rare state of the local standard of rest—which averages over the motions of all the stars in the vicinity of the sun.
Second, the Pentagon is about to deliver a report to Congress stating that some unidentified aerial phenomena (UAP) are real but that their nature is unknown. If UAP originated from China or Russia and were a national security risk, their existence would have never been revealed to the public. Hence, it is reasonable to conclude that the U.S. government believes that some of these objects are not human in origin. This leaves two possibilities: either UAP are natural terrestrial phenomena or they are extraterrestrial in origin. Both possibilities imply something new and interesting that we did not know before. The study of UAP should therefore shift from occupying the talking points of national security administrators and politicians to the arena of science where it is studied by scientists rather than government officials.
Many or even most UAP might be natural phenomena. But even if one of them is extraterrestrial, might there be any possible link to ‘Oumuamua?
The inferred abundance of ‘Oumuamua-like objects is unreasonably large if they’re of purely natural origin. With Amaya Moro-Martín and Ed Turner, I wrote a paper in 2009 calculating the number of interstellar rocks based on what is known about the solar system and assuming that these rocks were ejected from similar planetary systems orbiting other stars. The population of objects required to explain the discovery of ‘Oumuamua exceeds the expected number of interstellar rocks per unit volume by orders of magnitude. In fact, there should be a quadrillion ‘Oumuamua-like objects within the solar system at any given time, if they are distributed on random trajectories with equal probability of moving in all directions.
But the number is reasonable if ‘Oumuamua was an artificial object on a targeted mission towards the sun, aimed to collect data from the habitable region near Earth. One might even wonder whether ‘Oumuamua might have been retrieving data from probes that were already sprinkled on Earth at an earlier time. In such a case, ‘Oumuamua’s thin, flat shape could have been that of a receiver. Hence, ‘Oumuamua was pushed by sunlight not for the purpose of propulsion but as a byproduct of its thin flat shape. A similar push by reflection of sunlight without a cometary tail were the traits of an artificial rocket booster that was identified in 2020 by the same Pan-STARRS telescope that discovered ‘Oumuamua. This artificial object named 2020 SO was not designed to be a solar sail but had thin walls with a large surface-to-mass ratio for a different purpose.
At this time, the possibility that any UAP are extraterrestrial is highly speculative. But if we entertain this possibility for fun, then the tumbling motion of ‘Oumuamua could potentially have been meant to scan signals from all viewing directions. A predecessor to ‘Oumuamua could have been a craft that deposited small probes into the Earth’s atmosphere without being noticed, because it visited before Pan-STARRS started its operations. Along this imaginative line of reasoning, ‘Oumuamua could have arranged to appear as coming from the neutral local standard of rest, which serves as the local “galactic parking lot,” so that its origin would remain unknown.
But rather than simply wonder about possible scenarios, we should collect better scientific data and clarify the nature of UAP. This can be done by deploying state-of-the-art cameras on wide-field telescopes that monitor the sky. The sky is not classified; only government-owned sensors are. By searching for unusual phenomena in the same geographical locations from where the UAP reports came, scientists could clear up the mystery in a transparent analysis of open data.
As noted in my recent book Extraterrestrial, I do not enjoy science fiction stories because the story lines often violate the laws of physics. But we should be open-minded to the possibility that science will one day reveal a reality that was previously considered as fiction.
Strange Mega Comet Heading Towards our Solar System – UN271
“We have the privilege of having discovered perhaps the largest comet ever seen.”
It has not visited the solar system in more than 3 million years.
People here on Earth will likely need to rely on telescopes to capture photographs of it.
This is a big one.
A giant comet – which scientists say is arguably the largest comet discovered in modern times – is on its way toward the sun and will make its closest approach to Earth in 2031.
“We have the privilege of having discovered perhaps the largest comet ever seen – or at least larger than any well-studied one – and caught it early enough for people to watch it evolve as it approaches and warms up,” said University of Pennsylvania astronomer Gary Bernstein, a co-discoverer of the object.
It is the most distant comet to be discovered on its incoming path, giving us years to watch it evolve as it approaches the sun, the National Science Foundation said.
The comet is also an infrequent visitor to our neck of the woods: “It has not visited the solar system in more than 3 million years,” Bernstein said in a statement.
The comet, which is estimated to be 60 to 120 miles across, or about 10 times the diameter of most comets, is an icy relic flung out of the solar system by the migrating giant planets in the early history of the solar system.
This comet is quite unlike any other seen before, the National Science Foundation said, and the huge size estimate is based on how much sunlight it reflects.
At its current pace, the comet will travel from its current point just past Neptune’s orbit to nearly reach Saturn’s orbit in 2031, Smithsonian magazine said.
The object probably will only be about as bright as Pluto’s moon Charon at that point, according to New Atlas, so people here on Earth will likely need to rely on telescopes to capture photographs of it. Then it will head back into distant space from where it came.
The comet probably came from the Oort Cloud, which is believed to be a giant spherical shell that surrounds the solar system, according to NASA. Most long-period comets such as this one come from the Oort Cloud, NASA said.
It could be the largest object from the Oort Cloud ever detected, and it is the first comet on an incoming path to be detected so far away.Get the Coronavirus Watch newsletter in your inbox.
Astronomers suspect that there may be many more undiscovered comets of this size waiting in the Oort Cloud. These giant comets are thought to have been scattered to the far reaches of the solar system by the migration of Jupiter, Saturn, Uranus and Neptune early in their history.
The comet is dubbed Bernardinelli-Bernstein after the two astronomers who discovered it: Pedro Bernardinelli (also from the University of Pennsylvania) and Gary Bernstein. Its official name is 2014 UN271.
Astronomers once thought the universe could collapse in a Big Crunch. Now most agree it will end with a Big Freeze.
If the expanding universe could not combat the collective inward pull of gravity, it would die in a Big Crunch, like the Big Bang played in reverse. However, the cosmos is ballooning up at an ever-increasing rate, which makes most astronomers think the universe will die in a Big Freeze, where any lingering particles are separated by distances greater than the current observable universe.
How will the universe end? Humanity has pondered this question for thousands of years. And now science actually has the knowledge and tools to attempt an answer.
Until rather recently, astronomers thought the cosmos would repeatedly expand and collapse in an infinite cycle of cosmic death and rebirth. But the best evidence points to a distant Armageddon filled with more existential dread than the Book of Revelation. Trillions of years in the future, long after Earth is destroyed, the universe will drift apart until galaxy and star formation ceases. Slowly, stars will fizzle out, turning night skies black. All lingering matter will be gobbled up by black holes until there’s nothing left. Finally, the last traces of heat will disappear.
Alpha and Omega
The universe didn’t always seem destined to end this way. Roughly a century ago, astronomers thought that our Milky Way Galaxy was the entire universe. Our cosmos appeared static — it had always been, and would always remain, roughly the same. However, as Albert Einstein formulated his theories of relativity, he noticed signs of something strange. His equations implied a universe in motion, either expanding or contracting. So Einstein added a fudge factor — a cosmological constant — that held the universe in a more appealing steady state.
“Einstein was not being stupid; he was feeling the feeling of astronomers,” says Nobel Prize-winning cosmologist John Mather, the head scientist for NASA’s James Webb Space Telescope.
However, around the same time, astronomers began to accept that some of the fuzzy spiral-shaped nebulae they observed through their telescopes were not collections of stars in our galaxy. They were other galaxies entirely. And when Edwin Hubble meticulously measured their motions, he showed these galaxies were indeed moving away from our own. Humanity had discovered that the universe is expanding.
Pressing rewind on that expansion ultimately revealed that the entire universe was born in a violent Big Bang some 13.8 billion years ago. With its foundations firmly fixed, cosmology turned to the next great question: How will the universe end?
There are two main ways for an expanding universe to die: The cosmos could eventually collapse back in on itself, or it could continue inflating forever. To find out which is right, astronomers had to fast-forward the evolution of the universe.
There are a few ways the universe might end, but exactly how depends on how the rate of cosmic expansion changes in the future. If gravity overpowers expansion, the cosmos will collapse in a Big Crunch. If the universe continues to expand indefinitely, as expected, we’ll face a Big Freeze. But if dark energy pushes the expansion rate to near infinity, we’ll have a Big Rip that tears everything, even atoms, apart.
The Big Crunch
In 1922, Russian physicist and mathematician Alexander Friedmann derived a famous set of equations aptly named the Friedmann equations. These calculations showed that our universe’s destiny is determined by its density, and it could either expand or contract, rather than remain in a steady state. With enough matter, gravity would eventually halt the cosmos’ expansion, causing it to come crashing back inward.
In the 1960s and 1970s, when astronomers added up all the matter in the known universe, they calculated there was enough mass that the cosmos should ultimately collapse to an infinitely dense state, or perhaps even a gargantuan black hole.
Some speculated that once compressed into an infinitely small point — the Big Crunch — the universe would kickstart yet another expansion, or Big Bounce.
In the 1970s and 1980s, physicist John Wheeler, who helped coin the term black hole, became a leading proponent of the Big Crunch. To him, it was an obvious fate. A revolution in understanding black holes was underway, and Wheeler saw each one as an “experimental model” of the universe’s final state.
But Wheeler’s Big Crunch fondness was partially born from aesthetics, he admitted. It was easy to picture.
NASA’s Spitzer and WISE infrared observatories paired up to reveal this view of the region around the Milky Way’s supermassive black hole, Sagittarius A*. Supermassive black holes are likely to be the last reservoirs of matter in the entire universe. Yet even they will eventually evaporate.NASA/JPL-Caltech/Judy Schmidt
The Big Freeze
Unfortunately, reality is not always so relatable.
“Just because we might find a cold, empty universe an unappealing future doesn’t mean that that’s not where things are headed,” Columbia University physicist Peter Woit writes on his blog, Not Even Wrong.
In the late 1990s, two separate groups of scientists were surveying the distant universe, studying dying stars called type Ia supernovae, which serve as standard candles that help establish cosmic distances. They found distant blasts appeared dimmer, and were therefore farther away, than expected. The universe’s expansion wasn’t slowing down at all — it was speeding up. The teams had independently stumbled onto dark energy, shattering existing models of the universe. (See “The mystery of dark energy,” page 53.)
The expectation-defying discovery of dark energy showed the universe was very unlikely to collapse in a Big Crunch. Even with all the matter in the universe tugging inward, gravity will never be strong enough to overcome the inflating effect of dark energy. In other words, the ballooning universe is destined for a Big Freeze.
These days, astronomers think normal matter comprises just 5 percent of the universe’s contents. Meanwhile, dark matter makes up some 26 percent, and dark energy accounts for the final 69 percent. Dark energy, it turns out, seems to be the real-world force behind Einstein’s cosmological constant, which plays a major role in preventing a Big Crunch-style collapse.
Thanks to the expansion caused by dark energy, within a couple of trillion years, all but the closest galaxies will be too far away to see. Then, perhaps 100 trillion years later, star formation will cease, as dense stellar remnants like white dwarfs and black holes lock up any remaining material.
About a googol years from now — that’s a 1 followed by 100 zeroes — the last objects in the universe, supermassive black holes, will finish evaporating via Hawking radiation. After this, the universe enters a so-called Dark Era, where matter is just a distant memory.
The second law of thermodynamics suggests that entropy will keep increasing in a system (such as the cosmos) until it hits a maximum level. In real terms, that means that at some point, the universe will ultimately reach a state where all energy — and, hence, heat — is uniformly distributed. The final temperature of the entire universe will hover a smidge above absolute zero.
So, rather than mirroring Revelation, the death of our cosmos will likely resemble the beginning of Genesis: All will be empty and dark.
A solar storm was sent shooting towards the Earth by the Sun. Can the Internet shut down? Know how severe the online impact can be.
The Sun has hurled a solar storm into space and sent it careening on collision course towards the Earth. This poses multiple dangers here on the third rock from the Sun, especially to our digital world. How big an impact will it have on online infrastructure? Will our Internet be safe? Well, the Sun has an 11-year cycle during which it shoots out super-heated magnetised magma, referred to as ‘coronal mass ejections’ (CMEs) into space. The severity of the solar storm depends on which part of the cycle the Sun is in. Also, what is important is the location of the Earth in comparison to the trajectory of the solar flare. If an extremely severe solar storm is generated and the Earth is in its path, there will be a big impact on all communications devices including mobile phones, computers as well as electricity grids. However, if the Earth is not in the path of this severe solar storm, it escapes the destructive consequences.
Solar storm impact: If a really big solar storm was to hit the Earth, it would have an impact on our online activities – it could take down the Internet. How will solar storm affect online activities? Well, Science Focus explains the impact of a solar flare on Earth in an easy to understand manner, “If a CME on a similar scale was to strike the Earth today, it could damage the electronics in orbiting satellites, disrupting navigation and communications systems, as well as the GPS time synchronization that the internet relies on to function. It would also create a surge of electromagnetic radiation in the atmosphere, causing huge currents in our power grids which could burn out electrical transformers, leading to length(y) outages.” But remember, this is a worst-case scenario possibility.
For the past few years, the possibility of a new (and big!) planet hanging around in the outermost regions of the solar system has tantalized scientists and the public alike. But after years of searching, astronomers have found zero new planets in that realm.
We’ve only been studying the region of the solar system past the orbit of Neptune for a few decades now, and after a moment of introspection it’s easy to see why: astronomy out here is kind of challenging, because the objects we’re trying to hunt down are a) very, very small and b) very, very far away. That makes them hard to spot.
Besides Pluto, discovered by basically blind luck in 1930, our understanding of the outer solar system was completely absent until 1992, when astronomers found their first Kuiper Belt object, a frozen little remnant from the formation of the solar system, lazily circling the sun in near perfect darkness beyond Neptune.
Since then, we’ve found thousands more such objects, categorizing and subcategorizing them as we go (as astronomers are wont to do). For the rest of our story, we’ll be focusing on a class of characters known as extreme trans-neptunian objects, or eTNOs. If you’ve never heard that jargon term before, don’t be scared: it’s astronomese for “really, really far past the orbit of Neptune.”
In 2003, astronomers discovered perhaps the strangest eTNO yet, Sedna. Sedna is big, about half the size of Pluto, but sits in a truly ridiculous orbit. Over the course of 11,000 years (twice that of all of recorded human history), Sedna swings from 76 astronomical units (AU; one AU is the distance between the sun and Earth) to over 900 AU, then back again.
Sedna is weird.
The case for nine
The orbit of Sedna is so weird that it demands explanation. How can such a massive almost-planet reach such a huge, detached orbit without getting completely ejected from the solar system altogether?
Perhaps there’s something else out there, keeping Sedna on a leash.
More recently, a couple teams of astronomers began to notice some other funky eTNOs. Namely, a group of half a dozen objects with similar orbits — they had roughly the same amount of ellipticity, and those ellipses were clustered together.
Imagine picking up a random flower from a field and looking at the petals. You’d normally expect the petals to be distributed evenly around the flower, but if you saw them all clustered together you might think something suspicious was going on.
And the same goes for these strange eTNOs: there was no reason to expect these kinds of orbits by random chance. The best explanation, the astronomers claimed, was that a new planet, Planet Nine (until we come up with a better name), was shaping and shepherding them in their orbits.
But still eight remain
Click here for more Space.com videos…Join the search for Planet 9 – Here’s how!Look for the elusive Planet 9, brown dwarfs and more with NASA’s citizen scientist program Backyard Worlds.
It’s not a bad argument. The inability to explain the orbit of Uranus led to the detection of Neptune, so there is some historical antecedent to the strategy. And since then, more eTNOs have been found in the same strange, clustered orbits.Advertisement
But in the years since the claim of a ninth planet made headlines, astronomers haven’t snagged a picture of it. Which isn’t too worrisome, at least not yet: if Planet Nine exists, it is very small (relatively) and very far away, making it hard to spot.
And in that same time, other astronomers have weighed in, arguing that the special eTNOs aren’t so special after all. It could be that because of the way our surveys are designed and conducted, we’re simply more likely to spot eTNOs with these funky orbits, and not any of their friends with more normal orbits. In other words, these eTNOs aren’t shepherded by some mysterious entity in the outer solar system. There’s simply nothing to explain — they only look different because we haven’t finished looking yet.
What’s more, it’s hard to square the existence of a ninth planet with the formation of the solar system as we currently understand it. Astronomers can, of course, work to fold in a ninth planet (say, by arguing that it’s an ejected failed core of a planet or a captured rogue exoplanet), but the more complicated the scenario gets, the harder it is to swallow.
Without a smoking-gun picture of the planet, the astronomical community isn’t going to be fully swayed by the wayward motion of a handful of iceballs in the outer solar system. So for now the search for a new planet continues.
Extraterrestrial life refers to life forms that did not originate and are not indigenous to our planet. So this term covers all possible types of life outside the Earth: These can be viruses, but also plant-like life forms. Some go even further: they are looking for creatures that are very similar to humans in their complexity or even surpass them, popularly known as aliens. But if there is extraterrestrial life, why hasn’t anyone heard about it until now? Do so-called aliens even exist? The Fermi Paradox addresses this very question. What approaches there are to this you can find out here!
Why haven’t we found aliens yet?
A new paper on the Fermi paradox convincingly shows why we will probably never find aliens.
One summer night, when I was a child, my mother and I were scouring the night sky for stars, meteors, and planets.
Suddenly, an object with a light that pulsed steadily from bright to dim caught my eye. It didn’t have the usual red blinkers of an aircraft and was going far too slowly to be a shooting star.
Obviously, it was aliens.
My excitement was short-lived as my mother explained it was a satellite catching the sun as it tumbled along its orbit. I went to bed disappointed: The X-files was on TV twice a week back then, and I very much wanted to believe.
Today that hope is still alive and well, in Hollywood films, the public imagination, and even among scientists. Scientists first began searching for alien signals shortly after the advent of radio technology around the turn of the 20th century, and teams of astronomers across the globe have been taking part in the formal Search for Extraterrestrial Intelligence (SETI) since the 1980s.
Yet the universe continues to appear devoid of life.
Now, a team of researchers at the University of Oxford brings a new perspective to this conundrum. In early June, Anders Sandberg, Eric Drexler, and Toby Ord of the Future of Humanity Institute (FHI) released a paper that may solve the Fermi paradox — the discrepancy between our expected existence of alien signals and the universe’s apparent lack of them — once and for all.
Using fresh statistical methods, the paper re-asks the question “Are we alone?” and draws some groundbreaking conclusions: We Earthlings are not only likely to be the sole intelligence in the Milky Way, but there is about a 50 percent chance we are alone in the entire observable universe.
While the findings are helpful for thinking about the likelihood of aliens, they may be even more important for reframing our approach to the risk of extinction that life on Earth may face in the near future.
Where is everybody?
In 1950, while working at Los Alamos National Laboratory, physicist Enrico Fermi famously exclaimed to his colleagues over lunch: “Where is everybody?”
He had been pondering the surprising lack of evidence of other life outside of our planet. In a universe that had been around for some 14 billion years, and in that time developed more than a billion trillion stars, Fermi reasoned there simply must be other intelligent civilizations out there. So where are they?
We still don’t know, and the Fermi paradox has only strengthened with time. Since the 1950s, humans have walked on the moon, sent a probe beyond our solar system, and even sent an electric sports car into orbit around the sun for fun. If we can go from rudimentary wooden tools to these feats of engineering in under a million years, surely there would have been ample opportunity in our 13.8 billion-year-old universe for other civilizations to have progressed to a similar level — and far beyond — already?
And then, surely there would be some lingering radio signals or visual clues of their expansion reaching our telescopes.
How scientists try to tackle the Fermi paradox, and why this paper is different
Space is a large place, and the task of accurately estimating the likelihood of little green menisn’t exactly easy.
In 1961, astronomer Frank Drake proposed a formula that multiplied seven “parameters” together to estimate N, the number of detectable civilizations we should expect within our galaxy at a given moment in time:
The Drake equation was only intended as a rough tool to stimulate scientific discussion around the probability of extraterrestrial life. However, in the absence of any reasonable alternatives, it has remained astronomers’ only method of calculating the probability of extraterrestrial intelligence. This is problematic because while some parameters, such as R* — the rate of new star formation per year — are relatively well-known, others remain hugely uncertain.
Take L, the average lifespan of a detectable civilization. If we look at the average length of the past civilizations here on Earth, it wouldn’t be unreasonable to assume a low value. If the Romans, Incas, or Egyptians are anything to go by, it seems hard to make it past a few hundred years. On the flip-side, you could argue that once a civilization becomes technologically advanced enough to achieve interstellar travel, it could conceivably last many billions of years.
This enormous uncertainty leaves the Drake equation ultimately vulnerable to the optimism or pessimism of whoever wields it. And this is reflected in previous scientific papers whose results give values of N ranging anywhere from 10 to many billions.
As astronomer and SETI co-founder Jill Tarter eloquently put it in an interview with National Geographic in 2000: “The Drake Equation is a wonderful way to organize our ignorance.”
Sincere attempts to overcome this vulnerability have previously been made via selecting a handful of conservative, medium, and bullish best estimates for each parameter value and then taking an average across them.
In their new paper, titled “Dissolving the Fermi Paradox,” the FHI researchers dispute this method by demonstrating how this technique typically produces a value of N far higher than it should, creating the illusion of a paradox.
This is because simply selecting a few point estimates and plugging them into the Drake Equation misrepresents the state of our knowledge. As an example, imagine three scientists who have differing opinions on the value of L:
If you take a normal, linear average of all the possible integer values from one to 1000, you would implicitly factor scientist C’s opinion 90 times more than scientist A’s because their range of belief is 90 times larger. If you use a logarithmic scale to represent the above so that each scientist’s range corresponds to one order of magnitude, all three opinions will be represented more equally.
Therefore, the researchers represented the full range of possible values on a logarithmic scale and ran millions of simulations to obtain more statistically reliable estimates for N. They then applied a technique known as a Bayesian update to those results.That means mathematically incorporating the information that we have not discovered extraterrestrial intelligence yet (because the absence of evidence of aliens is evidence itself!).
This two-stage process produced striking results: Based upon the current state of astrobiological knowledge, there’s a 53 to 99.6 percent chance we are the only civilization in this galaxy and a 39 to 85 percent chance we are the only one in the observable universe.
This implies that life as we know it is incomprehensibly rare, and if other intelligences exist, they are probably far beyond the cosmological horizon and therefore forever invisible to us.
But life can’t be that rare, can it?
To be clear, the paper’s authors do not appear to be making any definitive claim about whether or not aliens exist; simply, our current knowledge across the seven parameters suggests a high likelihood of us being alone. As new information becomes available, they would update that likelihood accordingly.For example, if we discover a second instance of abiogenesis — the process of rudimentary life emerging from non-living matter — on a comet or another planet, then this would narrow the uncertainty on the fl parameter significantly.
Nonetheless, their results have certainly caused a stir, especially after SpaceX CEO Elon Musk tweeted them:
Many reacted to the paper’s findings by calling it anthropocentric and narrow-minded, arguing that any conclusion suggesting we Earthlings are somehow special is simply human arrogance.
This is somewhat understandable because the idea that intelligent life is extremely rare in the universe feels completely counterintuitive. We exist, along with other intelligent life like dolphins and octopi, so we assume what we see must be extrapolatable beyond Earth.
But this alone is not proof that intelligent civilizations are therefore ubiquitous.Whether the true likelihood is as high as one in two, or as inconceivable as one in a trillion trillion trillion, the mere ability to consciously ask ourselves that question depends on the fact that life has already successfully originated.
This phenomenon is known as an observer selection effect — a bias that can occur when thinking about the likelihood of an event because an observer has to be there to observe the event in the first place. As we only have one data point (us), we have no reliable way to predict the true likelihood of intelligent life. The only conclusion we can confidently draw is that it can exist.
So if we are alone, is this good or bad news?
Regardless of which side you take, the idea that we might be alone in the universe raises serious scientific and philosophical questions. Is our rareness something to celebrate or be disappointed by? What would it mean for humans to be the only conscious entities in the universe?
This last question matters hugely. Not only are we depleting our environmental resources at an unsustainable pace, but for the first time in the history of mankind, we’ve reached the technological stage where we hold the entire future of our species in our own hands.Within a few years we built enough nuclear weapons to exterminate every human on earth many times over and made these weapons available to our leaders on a hair-trigger. Each decade has brought us novel technologies with ever-increasing potential for both immense good and immense destruction.
As we rang in the new year, the Bulletin of Atomic Scientists moved the Doomsday Clock to the closest it has ever been to midnight. Meanwhile, estimates from various specialists in existential risksuggest somewhere between a 5 to 19 percent chance of complete human extinction by the end of this century — an unacceptably large probability considering the stakes.
Not only does this dark gamble affect the 7 billion of us alive today; if you factor in the moral weight of the billion billions of future people who would also never get to live out their existences, it becomes clear that we urgently need to get our collective act together.
As Carl Sagan famously said in his 1990 Pale Blue Dot speech: “In all this vastness, there is no hint that help will come from elsewhere to save us from ourselves. The Earth is the only world known so far to harbor life. … the Earth is where we make our stand.”
He’s not wrong, especially in light of this paper’s findings. If humanity really is the only civilization that may ever exist in this universe, then we shoulder a responsibility on a truly astronomical scale.
The Juno spacecraft made its most recent flyby of the giant planet Jupiter on June 8, 2021. Shortly before its closest point to Jupiter – the 34th of the mission, or perijove 34 – Juno flew closer to Jupiter’s large moon Ganymede than any spacecraft has in more than two decades. On July 14, NASA released the beautiful video above. It lets you ride along with the Juno spacecraft on this most recent sweep past Ganymede and Jupiter. The video is gorgeous and evocative. Juno’s principal investigator Scott Bolton of the Southwest Research Institute in San Antonio said in a statement:
The animation shows just how beautiful deep space exploration can be. It’s a way for people to imagine exploring our solar system firsthand by seeing what it would be like to be orbiting Jupiter and flying past one of its icy moons.
The images to make this time-lapse animation came from JunoCam, the visible-light camera/telescope aboard the Juno spacecraft. NASA
The 3:30-minute-long animation begins with Juno approaching Ganymede. It passed within 645 miles (1,038 km) of Ganymede’s surface at a relative velocity of 41,600 mph (67,000 kph). The imagery shows several of the moon’s dark and light regions. Darker regions are believed to result from ice sublimating into the surrounding vacuum, leaving behind darkened residue. The imagery also shows the crater Tros, which is among the largest and brightest crater scars on Ganymede.
It takes just 14 hours, 50 minutes for Juno to travel the 735,000 miles (1.18 million km) between Ganymede and Jupiter. The viewer is transported to within just 2,100 miles (3,400 km) above Jupiter’s spectacular cloud tops. By that point, Jupiter’s powerful gravity has accelerated the spacecraft to almost 130,000 mph (210,000 kph) relative to the planet.
Among the Jovian atmospheric features that can be seen are the circumpolar cyclones at the north pole and five of the gas giant’s string of pearls. These are eight massive storms rotating counterclockwise in Jupiter’s southern hemisphere. They appear as white ovals.
Using information that Juno has learned from studying Jupiter’s atmosphere, the animation team simulated lightning one might see as we pass over Jupiter’s giant thunderstorms.
How they made the video
Citizen scientist Gerald Eichstädt used composite images of Ganymede and Jupiter to give us the camera’s point of view. For both Ganymede and Jupiter, NASA said:
JunoCam images were orthographically projected onto a digital sphere and used to create the flyby animation. Synthetic frames were added to provide views of approach and departure for both Ganymede and Jupiter.
Juno mission extended to 2025
NASA said that, as planned, Jupiter’s gravitational pull has now affected Juno’s orbit. The craft has been in a highly elliptical polar orbit of 53 days since 2016. In other words, it has been passing close to the giant planet only that often. Now Jupiter’s strong gravity has reduced Juno’s orbit to 43 days.
The Juno mission was originally scheduled to end in July 2021. But in January of this year, NASA extended the mission. Juno will now continue exploring Jupiter through September 2025, or until the spacecraft’s end of life. NASA said on January 13, 2021:
This expansion tasks Juno with becoming an explorer of the full Jovian system – Jupiter and its rings and moons – with multiple rendezvous planned for three of Jupiter’s most intriguing Galilean moons: Ganymede, Europa, and Io.
The next Juno flyby of Jupiter, the 35th of the mission, is scheduled for a few days from now, July 21, 2021.
Bottom line: A beautiful video showing the most recent flyby of the Juno spacecraft at Jupiter. In the course of this flyby, Juno came closer to Jupiter’s large moon Ganymede than any spacecraft has in two decades.
These New Technologies Could Make Interstellar Travel Real
Long considered science fiction, leaving the solar system and speeding amid the stars may soon be within reach
(Credit: Charles Carter/Keck Institute for Space Studies via NASA)
On October 31, 1936, six young tinkerers nicknamed the “Rocket Boys” nearly incinerated themselves in an effort to break free of Earth’s gravity. The group had huddled in a gully in the foothills of California’s San Gabriel Mountains to test a small alcohol-fueled jet engine. They wanted to prove that rocket engines could venture into space, at a time when such ideas were widely met with ridicule. That goal was disrupted when an oxygen line caught fire and thrashed around wildly, shooting flames.
The Rocket Boys’ audacity caught the attention of aerodynamicist Theodore von Karman, who already worked with two of them at Caltech. Not far from the location of their fiery mishap, he established a small test area where the Rocket Boys resumed their experiments. In 1943, the site became the Jet Propulsion Laboratory (JPL), and von Karman its first director. JPL has since grown into a sprawling NASA field center with thousands of employees, yet it has managed to retain its founding motivation: test the limits of exploration, convention be damned.
They’ve had many successes over the years. In the early 1970s, JPL engineers built Pioneer 10, the first spacecraft to reach escape velocity from the solar system. A few years later, they followed up with Voyagers 1 and 2, the fastest of the many objects aimed at interstellar space. From the beginning of the Space Age to the launch of the Voyager spacecrafts — a span of just two decades — rocket scientists more than doubled flight speeds. But in the decades since, only one more spacecraft has followed the Voyagers out of the solar system, and nothing has done so at such a high speed. Now JPL’s rocketeers are getting restless again, and quietly plotting the next great leap.
The consistent theme of the new efforts is that the solar system is not enough. It is time to venture beyond the known planets, on toward the stars. John Brophy, a flight engineer at JPL, is developing a novel engine that could accelerate space travel by another factor of 10. Leon Alkalai, a JPL mission architect, is plotting a distant journey that would begin with an improbable, Icarus-esque plunge toward the sun. And JPL research scientist Slava Turyshev has perhaps the wildest idea of all, a space telescope that could provide an intimate look at a far-off Earth-like planet — without actually going there.
These are all long shots (not entirely crazy, according to Brophy), but if even one succeeds, the implications will be huge. The Rocket Boys and their ilk helped launch humans as a space-faring species. The current generation at JPL could be the ones to take us interstellar.
NASA’s Dawn spacecraft used ion propulsion to explore Ceres. Future missions could take the tech even further. (Credit: NASA-JPL/Caltech)
For Brophy, inspiration came from Breakthrough Starshot, an extravagantly bold project announced in 2016 by the late Stephen Hawking and Russian billionaire Yuri Milner. The ultimate aim of the project is to build a mile-wide laser array that could blast a miniature spacecraft to 20 percent the speed of light, allowing it to reach the Alpha Centauri star system (our closest stellar neighbor) in just two decades.
Brophy was skeptical but intrigued. Ambitious aspirations are nothing new for him. “JPL encourages people to think outside the box, and my wacky ideas are getting wackier in time,” he says. Even by that standard, the Starshot concept struck him as a little too far from technological reality. But he did begin to wonder if he could take the same concept but scale it down so that it might actually be feasible within our lifetimes.
What especially captivated Brophy was the idea of using a Starshot-style laser beam to help deal with the “rocket equation,” which links the motion of a spacecraft to the amount of propellant it carries. The rocket equation confronts every would-be space explorer with its cruel logic. If you want to go faster, you need more fuel, but more fuel adds mass. More mass means you need even more fuel to haul around that extra weight. That fuel makes the whole thing heavier still, and so on. That’s why it took a 1.4 million-pound rocket to launch the 1,800-pound Voyager probes: The starting weight was almost entirely fuel.
Since his graduate student days in the late 1970s, Brophy has been developing a vastly more efficient type of rocketry known as ion propulsion. An ion engine uses electric power to shoot positively charged atoms (called ions) out of a thruster at high velocity. Each atom provides just a tiny kick, but collectively they can push the rocket to a much greater velocity than a conventional chemical rocket. Better yet, the power needed to run the ion engine can come from solar panels — no heavy onboard fuel tanks or generators required. By squeezing more speed out of less propellant, ion propulsion goes a long way toward taming the rocket equation.
But ion engines come with drawbacks of their own. The farther they get from the sun, the more limited they are by how much electricity their solar panels can generate. You can make the panels huge, but then you add a lot of weight, and the rocket equation slams you again. And ion engines have such gentle thrust that they can’t leave the ground on their own; it then takes them a long time in space to accelerate to their record-breaking speeds. Brophy knows these issues well: He helped design the ion engine aboard NASA’s Dawn spacecraft, which just completed an 11-year mission to asteroid Vesta and dwarf planet Ceres. Even with its formidable 65-foot span of solar cells, Dawn went from zero to 60 in an unhurried four days.
An orbiting laser system could power an ion propulsion vehicle through the solar system, and prove reusable. (Credit: Jay Smith/Discover)
Ion the Prize
While Brophy was pondering this impasse between efficient engines and insufficient solar power, the Breakthrough Starshot concept came out, and it got the gears turning in his head. He wondered: What if you replaced sunshine with a high-intensity laser beam pointed at your spacecraft? Powered by the more efficient laser, your ion engine could run much harder while still saving weight by not having to carry your power source on board.about:blankabout:blank
Two years after his epiphany, Brophy is giving me a tour of an SUV-size test chamber at JPL, where he puts a high-performance ion engine through its paces. His prototype uses lithium ions, which are much lighter than the xenon ions Dawn used, and therefore need less energy to attain higher velocities. It also runs at 6,000 volts compared with Dawn’s 1,000 volts. “The performance of this thing would be very startling if you had the laser to power it up,” he says.
There’s just one minor issue: That laser does not exist. Although he drastically downsized the Starshot concept, Brophy still envisions a 100-megawatt space-based laser system, generating 1,000 times more power than the International Space Station, aimed precisely at a fast-receding spacecraft. “We’re not sure how to do that,” he concedes. It would be by far the biggest off-world engineering project ever undertaken. Once built, though, the array could be used over and over, with different missions, as an all-purpose rocket booster.
As an example, Brophy describes a lithium-ion-powered spacecraft with 300-foot wings of photovoltaic panels powering a full-size version of the engine he is developing at JPL. The laser would bathe the panels in light a hundred times as bright as sunshine, keeping the ion engine running from here to Pluto, about 4 billion miles away. The spacecraft could then coast along on its considerable velocity, racking up another 4 billion miles every year or two.
At that pace, a spacecraft could rapidly explore the dim areas where comets come from, or set off for the as-yet-undiscovered Planet 9, or go … almost anywhere in the general vicinity of the solar system.
“It’s like we have this shiny new hammer, so I go around looking for new nails to pound in,” Brophy says dreamily. “We have a whole long list of missions that you could do if you could go fast.”
Only the Voyager probes have passed the heliopause, leaving the sun’s influence. New probes may one day study the interstellar medium lying beyond. (Credit: NASA-JPL/Caltech)about:blankabout:blank
Interstellar Medium Well
After Brophy’s genial giddiness, it is a shock to talk to Alkalai, in charge of formulating new missions at JPL’s Engineering and Science Directorate. Sitting in his large, glassy office, he seems every bit the no-nonsense administrator, but he, too, is a man with an exploratory vision.
Like Brophy, Alkalai thinks the Breakthrough Starshot people have the right vision, but not enough patience. “We’re nowhere near where we need to be technologically to design a mission to another star,” he says. “So we need to start by taking baby steps.”
Alkalai has a specific step in mind. Although we can’t yet visit another star, we can send a probe to sample the interstellar medium, the sparse gas and dust that flows between the stars.
“I’m very interested in understanding the material outside the solar system. Ultimately, we got created from that. Life originated from those primordial dust clouds,” Alkalai says. “We know that there’s organic materials in it, but what kind? What abundances? Are there water molecules in it? That would be huge to understand.”about:blankabout:blank
The interstellar medium remains poorly understood because we can’t get our hands on it: A constant blast of particles from the sun — the solar wind — pushes it far from Earth. But if we could reach beyond the sun’s influence, to a distance of 20 billion miles (about 200 times Earth’s distance from the sun), we could finally examine, for the first time, pristine samples of our home galaxy.
Alkalai wants answers, and he wants to see the results firsthand. He’s 60, so that sets an aggressive schedule — no time to wait for giant space lasers. Instead, he proposes a simpler, albeit still unproven, technology known as a solar thermal rocket. It would carry a large cache of cold liquid hydrogen, protected somehow from the heat of the sun, and execute a shocking dive to within about 1 million miles of the solar surface. At closest approach, the rocket would let the intense solar heat come pouring in, perhaps by jettisoning a shield. The sun’s energy would rapidly vaporize the hydrogen, sending it racing out of a rocket nozzle. The combined push from the escaping hydrogen, and the assist from the sun’s own gravity, would let the ship start its interstellar journey at speeds up to 60 miles per second, faster than any human object yet —and it only gets faster from there.
“It’s very challenging, but we’re modeling the physics now,” Alkalai says. He hopes to begin testing elements of a thermal-rocket system this year, and then develop his concept into a realistic mission that could launch in the next decade or so. It would reach the interstellar medium another decade after that. In addition to sampling our galactic environment, such a probe could examine how the sun interacts with the interstellar medium, study the structure of dust in the solar system and perhaps visit a distant dwarf planet along the way.
It would be a journey, Alkalai says, “like nothing we’ve done in the past.”
How a solar gravitational lens works. (Credits: Courtesy of Slava Turyshev; The Aerospace Corp.; Jim Deluca/Jimiticus via YouYube (2); Jay Smith)
Catch A Glimpse
Solar thermal rockets and laser-ion engines, impressive as they may be, are still absurdly inadequate for crossing the tremendous gulf between our solar system and exoplanets — planets orbiting other stars. In the spirit of the Rocket Boys, Turyshev is not letting absurdity stop him. He is developing a cunning workaround: a virtual mission to another star.
Turyshev tells me he wants to send a space telescope to a region known as the solar gravitational lens (SGL). The area begins a daunting 50 billion miles away, though that’s still hundreds of times closer than our closest stellar neighbors. Once you get far enough into the SGL, something marvelous happens. When you look back toward the sun, any object directly behind it appears stretched out, forming a ring, and hugely magnified. That ring is the result of our star’s intense gravity, which warps space like a lens, altering the appearance of the distant object’s light.
If you position yourself correctly within the SGL, the object being magnified from behind the sun could be an intriguing exoplanet. A space telescope floating at the SGL, Turyshev explains, could then maneuver around, sampling different parts of the light ring and reconstructing the snippets of bent light into megapixel snapshots of the planet in question.
I have to interrupt him here. Did he say megapixel, like the resolution you get on your camera phone? Yes, he really is talking about an image measuring 1,000 by 1,000 pixels, good enough to see details smaller than 10 miles wide on a planet up to 100 light-years (600 trillion miles!) away.
“We could peek under the clouds and see continents. We could see weather patterns and topography, which is very exciting,” Turyshev says. He doesn’t mention it, but he doesn’t need to: That kind of resolution could also reveal megacities or other giant artificial structures, should they exist.
Assuming the JPL boffins can solve the transportation issues of getting to the SGL, the mission itself is fairly straightforward, if enormously challenging. Turyshev and his collaborators (Alkalai among them) will need to develop a Hubble-size space telescope,
or a mini-fleet of smaller telescopes, that can survive the 30-year journey. They will need to perfect an onboard artificial intelligence capable of running operations without guidance from home. Above all, they will need a target — a planet so intriguing that people are willing to spend decades and billions of dollars studying it. NASA’s TESS space telescope is doing some of that reconnaissance work right now, scanning for Earth-size worlds around local stars.
“Ultimately, to see the life on an exoplanet, we will have to visit. But a gravity lens mission allows you to study potential targets many decades, if not centuries, earlier,” Turyshev says merrily.
A journey to the SGL would take us beyond Alkalai’s baby steps, well onto the path toward interstellar exploration. It’s another audacious goal, but at least the odds of catching fire are much lower this time around.
NASA’s Mars rover Perseverance has sent pictures back to Earth of a unique rock formation within what the space agency called an “ancient lakebed” in its latest reported discovery during it mission on the Red Planet.
“Check out this patch of rock I found: looks kind of like garden pavers, and is probably exposed bedrock,” read a message from the research robot’s Twitter account on Wednesday. “Material like this, from the early days of this ancient lakebed, can help capture what that lake was like. Spending a few days investigating…”
Perseverance arrived on Mars on Feb. 18 after a six-month journey through space. The rover’s landing site was at the Jezero Crater, and “scientists believe the area was once flooded with water and was home to an ancient river delta,” according to NASA.
Check out this patch of rock I found: looks kind of like garden pavers, and is probably exposed bedrock. Material like this, from the early days of this ancient lakebed, can help capture what that lake was like. Spending a few days investigating…https://t.co/p9A2vJFjIVpic.twitter.com/0bc8lPiQLS— NASA’s Perseverance Mars Rover (@NASAPersevere) July 14, 2021
The rover is being assisted by Integrity, NASA’s Mars helicopter, which made its ninth flight on Mars earlier this month. Integrity made history on April 19 by completing the first controlled flight by an aircraft on a planet other than Earth.
“My science team is poring over these color images from the #MarsHelicopter’s latest flight,” Perseverance’s Twitter account posted last week along with video of Martian terrain. “Ingenuity crossed over a region that would be tricky for me to drive on, adding a new perspective to the picture of Jezero Crater that I’m piecing together.”
My science team is poring over these color images from the #MarsHelicopter’s latest flight. Ingenuity crossed over a region that would be tricky for me to drive on, adding a new perspective to the picture of Jezero Crater that I’m piecing together.