Newfound Comet ATLAS is getting really bright, really fast

A comet that passed by Earth in December 2018.

A comet that passed by Earth in December 2018.(Image: © NASA)

For years, amateur astronomers have been waiting for a bright, naked-eye comet to pass by Earth — and finally, such an object may have arrived. 

The possible celestial showpiece is known as Comet ATLAS, or C/2019 Y4. When it was discovered on Dec. 28, 2019, it was quite faint, but since then, it has been brightening so rapidly that astronomers have high hopes for the spectacle it could put on. But given the tricky nature of comets, skywatchers are also being cautious not to get their hopes up, knowing that the comet may fizzle out.ADVERTISING

It’s been awhile since a comet gave skywatchers a good show, particularly in the Northern Hemisphere. In March 2013, Comet PanSTARRS was visible right after sunset, albeit low in the western sky. But although it briefly attained first magnitude with a short, bright tail, its low altitude and a bright, twilight sky detracted from what otherwise would have been a much more prominent object. Comet Lovejoy in 2011 and Comet McNaught in 2007 both evolved into stunning objects, but unfortunately, when at their best, were visible only from the Southern Hemisphere. 

It has now been nearly a quarter of a century since we have been treated to a spectacularly bright comet: Comet Hale-Bopp passed by during the spring of 1997 and Comet Hyakutake did so exactly one year earlier. Both were truly “great” comets, very bright and fantastically structured; in very dark conditions, Hyakutake’s tail appeared to stretch more than halfway across the sky.

So now, after a “comet drought,” Comet ATLAS may finally enliven the evening skies of early spring. Or then again, maybe not.

Guarded optimism

The comet’s moniker is an acronym for Asteroid Terrestrial-impact Last Alert System (ATLAS), a robotic astronomical survey system based in Hawaii and optimized for detecting smaller near-Earth objects a few weeks to a few days before their closest approach. But on occasion, the survey will also find a comet.

When astronomers first spotted Comet ATLAS in December, it was in Ursa Major and was an exceedingly faint object, close to 20th magnitude. That’s about 398,000 times dimmer than stars that are on the threshold of naked-eye visibility. At the time, it was 273 million miles (439 million kilometers) from the sun. 

But comets typically brighten as they approach the sun, and at its closest, on May 31, Comet ATLAS will be just 23.5 million miles (37.8 million km) from the sun. Such a prodigious change in solar distance would typically cause a comet to increase in luminosity by almost 11 magnitudes, enough to make ATLAS easily visible in a small telescope or a pair of good binoculars, although quite frankly nothing really to write home about.

Except, since its discovery, the comet has been brightening at an almost unprecedented speed. As of March 17, ATLAS was already magnitude +8.5, over 600 times brighter than forecast. As a result, great expectations are buzzing for this icy lump of cosmic detritus, with hopes it could become a stupendously bright object by the end of May. 

A famous lineage

Another factor buoying hopes for ATLAS as a potential dazzler is that its orbit is nearly identical to that of the so-called Great Comet of 1844.

Like the 1844 comet, ATLAS follows a trajectory that would require 6,000 years per orbit and take it to beyond the outer reaches of the solar system, roughly 57 billion miles (92 billion km) from the sun. Probably in the far-distant past, a much larger comet occupied this same orbit, but fragmented into several pieces — including the 1844 comet and ATLAS — upon rounding the sun. 

But any comparison is dangerous. The 1844 comet was not discovered until shortly after perihelion, so we have no knowledge of its brightness behavior beforehand. But that information is currently all we know about ATLAS, and we won’t be able to see the object after it reaches the sun. 

And let’s not forget some of the comets of the past that seemingly had “glory” written all over them, only to utterly fail to live up to expectations: Comet ISON in 2013, Comet Austin in 1990 and Comet Kohoutek in 1974.

So what’s ahead?

John Bortle, who has observed hundreds of comets and is a well-known expert in the field, got his first look at Comet ATLAS through 15 x 70 binoculars on Sunday night (March 15). And he’s stumped, he wrote. “For the first time in many years I am left at a bit of a loss as to what honestly worthy advice I can offer would-be observers. I really don’t know quite what to make of this object.” 

The head (or coma) of Comet ATLAS is big, albeit “very faint and ghostly,” Bortle said, which doesn’t make sense. “If it’s a truly significant visitor, it should be considerably sharper in appearance. Instead we see, at best, a quite modestly condensed object with only a pinpoint stellar feature near its heart.” 

The unpredictability of comets is an old story. Astronomers use special formulas to try to anticipate how bright a comet will get. Unfortunately, comets’ individual behavior and characteristics can be as varied as people: No two are alike. 

Now, here is the conundrum regarding Comet ATLAS: Until a couple of weeks ago, it was brightening at an astounding rate. That brightening has slowed somewhat, but it is still an impossible rate of brightening to maintain. Were ATLAS to continue to brighten at this rate all the way to its closest approach to the sun at the end of May, it would end up rivaling the planet Venus in brightness! 

“We should expect the rate of increase to slow again,” Carl Hergenrother, an assiduous comet observer based in Arizona, said. “This is where it gets tricky for predicting just how bright it will get.” Right now, no one can predict how long it will continue to quickly brighten and how dramatically that brightening will slow.

Where to look and what to expect

The only thing left to do is to track Comet ATLAS in the days and weeks ahead. Fortunately, its path in March and April will be very favorable for Northern Hemisphere observers, as it will be circumpolar and always remain above the horizon. As darkness falls, it will be positioned more than halfway up in the north-northwest sky. Right now, the comet is in western Ursa Major, and it will shift into the boundaries of Camelopardalis the Giraffe — a rather dim, shapeless star pattern — by March 29. There it will stay, right on through the month of April.Advertisement

As to how bright Comet ATLAS will get, that’s anybody’s guess. It might become faintly visible to the naked eye under dark sky conditions by mid- or late April. By mid-May, when it disappears into the bright evening twilight, perhaps it will have brightened to second magnitude — about as bright as Polaris, the North Star. 

Whether ATLAS continues to overperform and shines even brighter, develops a significant tail or suddenly stops brightening altogether and remains very faint and ghostly are all unknown right now. We’ll just have to wait and see.

“It’s going to be fun the next few weeks watching Comet ATLAS develop (and provide a nice distraction from the current state of the world), Hergenrother wrote. “Here’s to good health and clear skies!”

Japan’s asteroid-smashing probe reveals a surprisingly young space rock

Ejecta curtain growth and deposition on the asteroid Ryugu after Japan's Hayabusa2 probe slammed an impactor into the space rock in April 2019.

Ejecta curtain growth and deposition on the asteroid Ryugu after Japan’s Hayabusa2 probe slammed an impactor into the space rock in April 2019.(Image: © JAXA, Kobe University, Chiba Institute of Technology, Kochi University, University of Occupational and Environmental Health)

A cannonball that a Japanese spacecraft fired at an asteroid is shedding light on the most common type of asteroid in the solar system, a new study reports.

Carbonaceous, or C-type, space rocks make up about three-quarters of known asteroids. Previous research suggests that they are relics of the early solar system that contain troves of primordial material from the nebula that gave birth to the sun and its planets about 4.6 billion years ago. This makes research into these carbon-rich asteroids essential to understanding planetary formation. 

To learn more about C-type asteroids, the Japan Aerospace Exploration Agency (JAXA) deployed the spacecraft Hayabusa2 to Ryugu, a 2,790-foot-wide (850 meters) near-Earth asteroid that is one of the darkest celestial bodies in the solar system. The C-type asteroid’s name, which means “dragon palace,” refers to a magical underwater castle from a Japanese folk tale. 

In 2018, Hayabusa2 arrived at Ryugu to scan it from orbit and deploy multiple rovers on the boulder-covered asteroid. Scientists found that Ryugu is likely a loosely packed, very porous pile of rubble, about 50% empty space.

To shed light on Ryugu’s composition and structure, Hayabusu2 shot a 4.4-lb. (2 kilograms) copper cannonball a bit larger than a tennis ball at about 4,475 mph (7,200 km/h) at the asteroid. The impact carved out an artificial crater that exposed pristine material under Ryugu’s surface for remote analysis and blasted out a plume of ejected material. Hayabusa2’s cameras recorded the evolution of this plume in detail.

The number and size of craters that pockmark asteroids such as Ryugu can help scientists estimate the age and properties of asteroid surfaces. These analyses are based on models of how such craters form, and data from artificial impacts like that on Ryugu can help test those models.

The cannonball, dubbed the Small Carry-on Impactor (SCI), blasted out a crater about 47.5 feet (14.5 m) wide with an elevated rim and a central conical pit about 10 feet (3 m) wide and 2 feet (0.6 m) deep. 

“I was so surprised that the SCI crater was so large,” study lead author Masahiko Arakawa, a planetary scientist at Kobe University in Japan, told Space.com. The crater was about seven times larger than what might be expected from a comparable scenario on Earth, he added.

The artificial crater was semicircular in shape, and the curtain of ejected material was asymmetrical. Both of these details suggest that there was a large boulder buried near the impact site, the researchers said. This conclusion matches the rubble-pile picture that scientists already had of Ryugu.Click here for more Space.com videos…Watch Asteroid Debris Fly During Japan’s Hayabusa2’s 2nd TouchdownVolume 0% PLAY SOUND

Features of the artificial crater and the plume suggested that the growth of a crater was limited mostly by the asteroid’s gravity and not by the strength of the space rock’s surface. This, in turn, suggested that Ryugu has a relatively weak surface, one only about as strong as loose sand, which is consistent with recent findings that Ryugu is made of porous, fragile material.

These new findings suggest that Ryugu’s surface is about 8.9 million years old, while other models suggested that the asteroid’s surface might be up to about 158 million years old. All in all, while Ryugu is made of materials up to 4.6 billion years old, the asteroid might have coalesced from the remains of other broken-apart asteroids only about 10 million years ago, Arakawa said.

The scientists detailed their findings online Thursday (March 19) in the journal Science.

Asteroid Ryugu has texture like ‘freeze-dried coffee’

The asteroid Ryugu has a texture that is highly porous, new images from a Japanese space reveal.

“It is something like freeze-[dried] coffee,” planetary scientist Tatsuaki Okada of the Japanese Aerospace Exploration Agency explained to Science News.

Ryugu’s heat map shows that it’s about 50 percent porous, meaning half of it is holes, Okada and colleagues report. Even most of the asteroid’s large boulders appear porous.

The Hayabusa2 spacecraft measured the maximum temperatures during one full rotation of the asteroid Ryugu and found that most of the asteroid stays cool. (T. Okada et al/Nature 2020 )

The Hayabusa2 spacecraft measured the maximum temperatures during one full rotation of the asteroid Ryugu and found that most of the asteroid stays cool. (T. Okada et al/Nature 2020 ) (T. Okada et al/Nature 2020)

Science News reports the airiness of the rock’s texture fits with the idea that Ryugu is essentially a chunk of rubble created from the breakup of a larger mass about 700 million years ago.

“This might be common for the asteroids and even for planetesimals in the early solar system,” Okada says.

The researchers reported their observations Monday in the journal Nature.

The Intense Heat from the Sun Helps Ice Form on Mercury. Wait… What?

While the scorching planet Mercury might not be the first place you’d think to look for ice, the MESSENGER mission confirmed in 2012 that the planet closest to the Sun does indeed hold water ice in the permanently-shadowed craters around its poles.  But now a new study regarding Mercury’s ice provides even more counter-intuitive details about how this ice is formed. Scientists say heat likely helps create some of the ice.

Brant Jones, a researcher in Georgia Tech’s School of Chemistry and Biochemistry and the study’s first author, said this isn’t some strange, crazy idea. While it’s a bit complicated, it’s mostly just basic chemistry.

The planet’s extreme daytime heat combined with the super-cold (minus 200-degree Celsius) temperatures in the permanently shadowed craters might be acting like an “ice-making chemistry lab.”

Despite Mercury’s daytime heat, there is permanent ice at the poles, according to data and images from the MESSENGER mission. Credit: NASA / MESSENGER

“There is a surprising amount of ice on Mercury and significantly more than on the Moon,” Brant told Universe Today.

The process for creating ice on Mercury is similar to what happens on the Moon. Back in 2009, scientists determined electrically charged particles from the Sun’s solar wind were interacting with the oxygen present in some dust grains on the lunar surface to produce hydroxyl. Hydroxyl (OH) is just one atom of hydrogen with an oxygen atom, instead of the two hydrogen atoms found in water.

Brant worked with other scientists, including colleague Thomas Orlando, also from Georgia Tech, to refine the understanding of that process. In 2018, they published a paper that showed that while this process on the Moon produced significant amounts of hydroxyls, it produced very little molecular water.

“Though the solar wind was suggested as a potential source term in the 2009 observations of water on the Moon,” Orlando said via email, “the mechanisms were never really identified. We modeled this for the Moon but the importance was not as significant on the Moon due to the overall much lower temperatures.”   

But they knew this process could also take place on asteroids, Mercury or any other surface that is bombarded by the solar wind.

“In order to create molecular water, you need one more ingredient, and that is heat,” said Brant. 

Scientists model a feasible chemical reaction, in which the Vulcan heat on Mercury could help it make ice at its poles. Georgia Tech’s Thom Orlando (l.) is the new Mercury study’s principal investigator. Brant Jones (r.) is first author. Credit: Georgia Tech / Rob Felt

Daytime temperatures on Mercury can reach 400 degrees Celsius, or 750 degrees Fahrenheit.

Minerals in Mercury’s surface soil contain what are called hydroxyl groups. The extreme heat from the Sun helps to free up these hydroxyl groups then energizes them to smash into each other to produce water molecules and hydrogen that lift off from the surface and drift around the planet.

Some water molecules are broken down by sunlight and dissipate. But other molecules land near Mercury’s poles in deep, dark craters that are shielded from the Sun. The molecules get trapped there and become a part of the growing, permanent glacial ice housed in the shadows.

“It’s a little like the song Hotel California. The water molecules can check in to the shadows but they can never leave,” said Orlando in a press release.

“The total amount that we postulate that would become ice is 1013 kilograms (10,000,000,000,000 kg or 11,023,110,000 tons) over a period of about 3 million years,” Jones said. “The process could easily account for up to 10 percent of Mercury’s total ice.”

The data used for their study comes from the MESSENGER spacecraft, which orbited Mercury between 2011 and 2015, studying the planet’s chemical composition, geology, and magnetic field. MESSENGER’s findings of polar ice corroborated previous signatures for ice picked up years earlier by Earth-based radar.

What Did Mariner 10 See During Its Historic Journey To Venus and Mercury?

Mariner 10 was the first spacecraft sent to the planet Mercury; the first mission to explore two planets during a single mission; the first to use a gravity assist to change its flight path; the first to return to its target after an initial encounter; and the first to use the solar wind as a major means of spacecraft orientation during flight. But what did it capture with its two onboard cameras?

During its flyby of Venus, Mariner 10 discovered evidence of rotating clouds and a very weak magnetic field. Using a near-ultraviolet filter, it photographed Venus’s chevron clouds and performed other atmospheric studies.

The spacecraft flew past Mercury three times. Owing to the geometry of its orbit – its orbital period was almost exactly twice Mercury’s – the same side of Mercury was sunlit each time, so it was only able to map 40–45% of Mercury’s surface, taking over 2,800 photos. It revealed a more or less Moon-like surface. It thus contributed enormously to our understanding of Mercury, whose surface had not been successfully resolved through telescopic observation. The regions mapped included most or all of the Shakespeare, Beethoven, Kuiper, Michelangelo, Tolstoj, and Discovery quadrangles, half of Bach and Victoria quadrangles, and small portions of Solitudo Persephones (later Neruda), Liguria (later Raditladi), and Borealis quadrangles.[77]

Mariner 10 also discovered that Mercury has a tenuous atmosphere consisting primarily of helium, as well as a magnetic field and a large iron-rich core. Its radiometer readings suggested that Mercury has a night time temperature of −183 °C (−297 °F) and maximum daytime temperatures of 187 °C (369 °F).

Planning for MESSENGER, a spacecraft that surveyed Mercury until 2015, relied extensively on data and information collected by Mariner 10.

Where is Telsa’s Starman?

On February 6, 2018, at 2045 UTC, the first Falcon Heavy was launched into space. It contained a very special payload- a Tesla Roadster with Starman.

But where is this vehicle? The current location is 203,837,502 miles (328,044,762 km, 2.193 AU, 18.24 light minutes) from Earth, moving toward Earth at a speed of 18,756 mi/h (30,184 km/h, 8.38 km/s).

The car is 90,671,738 miles (145,922,063 km, 0.975 AU, 8.11 light minutes) from Mars, moving toward the planet at a speed of 9,603 mi/h (15,454 km/h, 4.29 km/s).

The car is 149,430,277 miles (240,484,795 km, 1.608 AU, 13.37 light minutes) light minutes from the Sun, moving away from the star at a speed of 6,842 mi/h (11,011 km/h, 3.06 km/s).

The car has exceeded its 36,000 mile warranty 29,614.4 times while driving around the Sun, (1,066,119,513 miles, 1,715,753,572 km, 11.47 AU) moving at a speed of 46,644 mi/h (75,066 km/h, 20.85 km/s). The orbital period is about 557 days.

It has achieved a fuel economy of 8,461.3 miles per gallon (3,597.3 km/liter, 0.02780 liters/100 km), assuming 126,000 gallons of fuel.

If the battery was still working, Starman has listened to Space Oddity 208,809 times since he launched in one ear, and to Is there Life On Mars? 281,362 times in his other ear.

Astrophotographer Spots Elon Musk’s Roadster Cruising Through Space 

Starman has completed about 1.380 orbits around the Sun since launch.

A telescope about 48,145 ft (14,675 m) in diameter would be required to resolve the Upper stage from Earth. A smaller one could see him as an unresolved dot, about 92.6 ft (28.2 m) in diameter, in ideal conditions.

The vehicle has traveled far enough to drive all of the world’s roads 47.2 times.

It has been 2 years, 1 month, 9 days, 8 hours, 49 minutes and 33 seconds since launch.

Is life possible around black holes?

Artist's illustration of a black hole.

Artist’s illustration of a black hole.(Image: © NASA)

We’re used to thinking of possible homes for life on watery worlds orbiting stars like the sun, but a new research paper has found a new potential habitat: a rocky planet orbiting just past the event horizon of a rapidly spinning supermassive black hole

The exotic forces around that black hole are able to warm up the planet just right, but the scenario comes with a catch: the planet must orbit at nearly the speed of light.

Habitat for humanity

We don’t know all the possible places that life could arise in our universe, because so far we only have one example: us. And while scientists (and sci-fi authors) enjoy thinking about all sorts of exotic arrangements and possibilities for lifeforms, for serious searches of extraterrestrial intelligence, our best bet is to use our own circumstances as a template, hunting for life that isn’t too dissimilar to what we find on Earth.

From that, we can draw two extremely broad requirements. One, life like our own requires liquid water. Water is the most common molecule in the universe, composed of hydrogen (element No. 1 when it comes to abundance in the cosmos) and oxygen (the byproduct of fusion reactions inside stars like our sun, making it also very common). But that water is usually either vaporized into a plasma (and hence very bad for life) or locked down in its solid, frozen state as ice (also not very good for life).

The liquid stuff is harder to come by, and requires a source of heat that isn’t so hot that water just evaporates. We’ve found this perfect balance in only two kinds of locations: the so-called “habitable zone” of stars, a band of orbits where the light output it just right; and buried underneath the icy crusts of certain moons of the outer planets in our solar system, where tidal heating generates the necessary energy.

But just raw heat isn’t enough. Life is a complex process that uses energy to do interesting things (like move around, eat and reproduce). All those processes are not perfectly efficient, so they generate waste heat. This waste heat must be dumped safely away from the environment; otherwise, you end up with nightmare greenhouse scenarios, with temperatures escalating to uncontrolled levels and killing off any life that got started.

On the Earth, we dump our waste heat into the vacuum of space itself in the form of infrared radiation. This contrast, between a source of energy and a place to put all the waste, enables life to flourish on our home planet, and presumably any other planet with a similar setup.

Warm monsters

At first glance, black holes appear to be the least inviting homes for any potential lifeforms. After all, they are objects made of pure gravity, pulling in anything that gets too close beneath their event horizons, shutting them off from further contact with the rest of the universe forever. Nothing, not even light, can escape their gravitational maw. 

Black holes don’t give off light themselves — they’re black, after all — but that inescapable gravity can provide a surprise, unique to them throughout the cosmos.

Permeating the universe is something called the cosmic microwave background (CMB). The CMB is the leftover radiation from when the universe was just a baby, only 380,000 years old. It is, by far, the greatest source of radiation in the entire cosmos, easily swamping all the stars and galaxies by many orders of magnitude. The reason you don’t see it is that it’s primarily in the microwave region of the electromagnetic spectrum (hence the name).

In other words, the CMB is cold, with a temperature just about 3 degrees above absolute zero.

But as that CMB light falls into a black hole, it becomes blueshifted, bumped to higher and higher energies from the extreme gravity. Just before it hits the event horizon, CMB light can gain so much energy that it shifts into infrared, visible and even ultraviolet portions of the spectrum.

In other words, near a black hole, the CMB stops being cold, and gets very, very hot.

What’s more, if the black hole is spinning, it’s able to focus the light into a narrow beam, making the CMB appear as a single spot on the sky. Kind of like a sun.Click here for more Space.com videos…Search for Alien Life – Decades of Earth Observations a KeyVolume 0% PLAY SOUND

Goldilocks

So if you’re able to get close enough to a black hole, you’ll find yourself surprisingly warm, and if you’re a planet, you might just find your water ice converted into liquid water oceans — a potential home for life.

But for life to thrive, it also needs a heat sink, which can handily be provided by the black hole itself. Close to the black hole, gravitational distortions enlarge the appearance of the event horizon, swelling it far larger than you might naively think. 

Close enough to the black hole (say, at a radius less than 1% above the event horizon), the hot CMB shrinks to fill only a small disk, while the event horizon swells to cover 40% of the sky. If your planet is rotating, you then have a “sun” and a “night” — and life has everything it needs to do its business.

But orbits at this radius are usually extremely unstable, prone to just falling all the way into the terrible blackness itself. Recently, a team of researchers published an analysis in The Astrophysical Journal, exploring this scenario to see if there was any way to stabilize the situation. 

And they found a way to make it work. If the black hole is big, at least 1.6×108 times the mass of the sun, and rapidly spinning, then it hosts a “habitable zone” just barely above the event horizon, where the CMB light peaks in the UV part of the spectrum — hot, but not terrible. Any closer and the planet would be destroyed by extreme gravitational forces, and any farther and the CMB would be too cold. But in that narrow band? Just right.

Though this scenario is possible, it wouldn’t be very pretty. The planet would have to orbit at nearly the speed of light, experiencing a time dilation factor of thousands — meaning that for every second that goes by on that world, hours would slide by for us. And who knows if a planet could even find its way that close to a black hole while still surviving.

Still, the work shows that we have to keep our minds open when it comes to potential homes for life, up to and including some of the most terrible environments in the universe.

Planet 9 discovery gets closer as astronomers discover 139 ‘minor planets’ past Neptune

Astronomers are getting closer to discovering the elusive and mysterious Planet Nine after 139 “minor planets” were discovered past Neptune’s orbit.

These objects, ones “that were not previously published,” are not officially planets or comets, but rather space objects that orbit the Sun. In total, the discovery is five percent of the trans-Neptunian object (TNO) population, bringing the number to approximately 3,000, according to a statement accompanying the study.

“Pluto, the best-known TNO, is 40 times farther away from the sun than Earth is, and the TNOs found using the [Dark Energy Survey] data range from 30 to 90 times Earth’s distance from the sun,” the statement reads. “Some of these objects are on extremely long-distance orbits that will carry them far beyond Pluto.”

Artist's illustration of Planet Nine, a hypothetical world that some scientists think lurks undiscovered in the far outer solar system.

Artist’s illustration of Planet Nine, a hypothetical world that some scientists think lurks undiscovered in the far outer solar system. (R. Hurt (IPAC)/Caltech)

The researchers used data from the DES between 2013 and 2017, which uses a 520-megapixel Dark Energy Camera. It is on the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory in Chile.

There were 7 billion DES-detected dots that the researchers started with, a list that was condensed to 22 million “transient” objects and then eventually, approximately 400 objects that were observed over six separate nights.

“We have this list of candidates, and then we have to make sure that our candidates are actually real things,” the study’s lead author, Pedro Bernardinelli, said in the statement.

The objects range between 30 and 90 astronomical units from the sun. One astronomical unit is the equivalent of 93 million miles or the distance between the Earth and the sun.

“Dedicated TNO surveys have a way of seeing the object move, and it’s easy to track them down,” Bernardinelli added. “One of the key things we did in this paper was figure out a way to recover those movements.”

It’s expected that the discovery could play a role in further searches for TNOs, notably the infamous Planet 9.

“There are lots of ideas about giant planets that used to be in the solar system and aren’t there anymore, or planets that are far away and massive but too faint for us to have noticed yet,” the study’s co-author Gary Bernstein said. “Making the catalog is the fun discovery part. Then, when you create this resource, you can compare what you did find to what somebody’s theory said you should find.”

The study was published in The Astrophysical Journal Supplement Series.

EVIDENCE OF PLANET NINE?

A hypothetical planet that has been described as “the solar system’s missing link,” Planet 9 (also known as Planet X) has been part of the lexicon for several years, first mentioned in 2014. It was brought up again in 2016, when Caltech astrophysicists Mike Brown and Konstantin Batygin first wrote about it.

In October 2017, Batygin said that there are “five different lines of observational evidence” that point to the existence of Planet Nine.

The five lines of evidence are:

  • Six known objects in the Kuiper Belt, all of which have elliptical orbits that point in the same direction.
  • The orbits of the objects are all tilted the same way; 30 degrees “downward.”
  • Computer simulations that show there are more objects “tilted with respect to the solar plane.”
  • Planet Nine could be responsible for the tilt of the planets in our solar system; the plane of the planet’s orbit is tilted about 6 degrees compared to the Sun’s equator.
  • Some objects from the Kuiper Belt orbit in the opposite direction from everything else in the solar system.

“No other model can explain the weirdness of these high-inclination orbits,” Batygin said at the time. “It turns out that Planet Nine provides a natural avenue for their generation. These things have been twisted out of the solar system plane with help from Planet 9 and then scattered inward by Neptune.”

In October 2017, NASA released a statement saying that Planet 9 might be 20 times further from the Sun than Neptune is, going so far as to say “it is now harder to imagine our solar system without a Planet 9 than with one.”

Some researchers have suggested the mysterious planet may be hiding behind Neptune and it may take up to 1,000 years before it’s actually found.

Two studies published in March 2019 offered support of its existence, however, a separate study published in September 2019 suggested the theoretical object may not be a giant planet hiding behind Neptune — but rather a primordial black hole.

A study published in January 2019 suggested that some of the farthest celestial bodies in our planetary system aren’t being impacted by this yet-to-be-discovered planet, but rather another mysterious object deep in the echoes of space.

NASA’s plan to save Earth from a giant asteroid

65 million years ago, a large asteroid collided with Earth near present-day Chicxulub, Mexico. The impact was a climactic event that likely contributed to dinosaur extinction. Today, Earth remains vulnerable to asteroid collisions.

In recent history, space rocks have landed in The United States, Russia, and elsewhere. In the event of a potential asteroid collision, NASA has developed several options for dealing with the threat. Researchers at NASA’s Center for Near Earth Object Studies and Jet Propulsion Laboratory have proposed using blunt force, weaponized deflection or a theoretical tool called a gravity tractor to deflect impact. In addition to developing contingency plans, NASA scientists are also searching the sky for future asteroid threats.

  • If a giant asteroid were to hit the Earth, NASA and FEMA have a plan. 
  • Although an asteroid of that size would be rare — NASA estimates a one-mile-wide asteroid only hits the Earth once every one million years — the two agencies have performed multiple test runs to ensure we’d be prepared. 
  • “It’s not a matter of if, but when, we will deal with such a situation,” said astrophysicist Thomas Zurbuchen.

Earth bacteria may have colonized other solar systems


Astronomers suggest microbes might hitch lifts on interstellar asteroids.


Was bacteria one of our early exports? A new paper twists the already controversial notion of panspermia.
BERNT OVE MOSS / EYEEM, VIA GETTY IMAGE

Could the Earth be a life-exporting planet? That’s the curious question examined in a recent paper written by Harvard University astronomers Amir Siraj and Abraham Loeb.

The researchers take a novel twist on the controversial notion of panspermia – the idea, propelled into the mainstream in the early 1970s by astronomers Fred Hoyle and Chandra Wickramasinghe, that life might have started on Earth through microbes arriving from space.

The theory is generally discounted, although eminent astrophysicists such as Stephen Hawking conceded it was at least possible, and a major paper published in 2018 revived the topic big-time.

In their paper, Siraj and Loeb reverse the standard assumption about the direction of the microbial journey and ask whether it is possible to that at some point Earth-evolved bacteria could have been propelled away from the planet, possibly to be deposited somewhere else in the Milky Way.

To examine the idea, they fed several bits of evidence, and a few reasonable assumptions, into a computer and let the numbers run.

First and foremost, they rely on evidence from several studies that confirm the existence of airborne microbial colonies as high as 77 kilometres above the surface of the planet. The authors note that “the abundance of microbes in the upper atmosphere is poorly constrained”, so the density of life in the upper reaches remains largely guesswork.

Also unknown at this point is whether bacteria colonies persist above 100 kilometres up.

Over our heads: a brief history of panspermia

In the absence of any extraterrestrial versions of dirt-sampling spacecraft such as Japan’s Hayabusa asteroid-lander, the only viable transport methods for shipping microbes out of Earth’s atmosphere, the researchers say, are long-period comets and interstellar objects.

The comets, they note, “can easily be ejected from the Solar System by gravitational interactions with planets due to their low gravitational binding energies and planet-crossing orbits”. Interstellar objects are new to the scenario, their existence well demonstrated by the recent discoveries of ‘Oumuamua and 2I/Borisov – both high-speed big lumps of rock that entered the solar system from elsewhere.

At particular speeds and particular angles, they calculate, both comets and asteroids could come close enough to Earth to “graze” its upper atmosphere before being flung out of the Solar System with the aid of a gravitational slingshot generated by the close encounter.

During such an interaction, the objects would inevitably plough through the airborne bacterial colonies – the researchers cite Bacillus subtilisDeinococcus radiodurans, Escheria coli, and Paracoccus denitrificans as the most likely candidates.

Sufficient numbers of the newly gathered passengers, the modelling shows, would survive the g-forces of the slingshot acceleration and the friction-induced heating caused by leaving the atmosphere.

Siraj and Loeb calculate that across the life of Earth, between one and 10 comets and between one and 50 interstellar objects have come close enough to graze the atmosphere.

Previous research has shown that bacteria could easily survive on board an asteroid or comet in interstellar space – lapsing into suspended animation if necessary – and could just as easily survive the enormous pressure caused by their transport smacking into a planet.

Thus, the researchers conclude that although much more research is needed – particularly into the make-up and distribution of microbes in the upper atmosphere – the idea of panspermia beginning on this planet and heading outwards is “realistic”.

The truth of the matter might never be known, of course, at least for several centuries; but it is at least possible that somewhere many light years hence there is a corner of a distant solar system that is forever Earth.

All Alone in Interstellar Space, Voyager 2 Is About to Lose Contact With Home

It’s lonely out there in deep space. Especially when a spacecraft has travelled so far into the vast emptiness, interstellar space is now all it can truly call home.

Of course, this was always Voyager 2’s fate. The spacecraft – which launched over 40 years ago and now stands as NASA’s longest-running space mission – was designed to venture out to the boundaries of our Solar System. For decades, it’s done just that, but the incredible voyage is about to encounter a challenge it hasn’t faced in all that long, lonesome journeying.

NASA has announced that Deep Space Station 43 (DSS–43) – the only antenna on Earth that can send commands to the Voyager 2 spacecraft – is going silent, and not for a short time.

The giant dish, located in Australia, and roughly the size of a 20-storey office building, requires critical upgrades, the space agency says. The Canberra facility has been in service for almost 50 years, so it’s not surprising that the ageing hardware needs maintenance.

010 voyager 2 sDSS–43. (CDSCC)

Nonetheless, the work comes at a cost. For approximately 11 months – until the end of January 2021, when the repairs are expected to be complete – Voyager 2 will be totally alone, coasting into the unknown in a quiescent mode of operation designed to conserve power and keep the probe on course until DSS–43 comes back online.

“We put the spacecraft back into a state where it will be just fine, assuming that everything goes normally with it during the time that the antenna is down,” explains Voyager project manager Suzanne Dodd from NASA’s Jet Propulsion Laboratory.

“If things don’t go normally – which is always a possibility, especially with an ageing spacecraft – then the onboard fault protection that’s there can handle the situation.”

During this almost year-long period of radio silence, the silence will only be one-way. Other antennas in the Canberra Deep Space Communication Complex (CDSCC) will be configured to receive any signals Voyager 2 broadcasts to Earth; it’s just that we won’t be able to say anything back, even if we need to.

010 voyager 2 sArtist’s concept of Voyager 2. (NASA/JPL-Caltech)

While NASA has done everything it can to prepare Voyager 2 for the communications blackout, it’s still a gamble – a calculated one, sure, but also seemingly an unprecedented predicament in the long duration of this historic space mission.

“There is risk in this business as there is in anything in spaceflight,” CDSCC education and public outreach manager Glen Nagle told The New York Times. “It’s a major change and the longest downtime for the dish in the eighteen years I’ve been here.”

According to the space agency, the biggest unknowns are whether Voyager 2’s automated thrust control systems – which fire several times a day to keep the probe’s antenna oriented towards Earth – will work accurately for such an extended period, and whether power systems designed to keep Voyager 2’s fuel lines sufficiently heated will also do their job.

The new challenge comes only days after NASA confirmed the spacecraft had resumed normal operations following a scare in January, when an anomaly triggered Voyager’s autonomous fault protection routines.

The malfunction meant the spacecraft failed to perform a scheduled flight manoeuvre on January 25. Painstaking assessments from NASA engineers on Earth ultimately fixed the issue, with controllers having to wait 34 hours for each single response from Voyager 2, given the 17-hour transmission time for signals to travel to and from the distant probe.

Rectifying the problem involved turning five key scientific instruments off and turning them back on again – something that reportedly had never been done before – but luckily the reboot worked a charm.

Here’s hoping the next 11 months proves equally successful for the far-flung Voyager 2, currently located over 17 billion kilometres (roughly 11 billion miles) from Earth, and scientifically confirmed to have now entered interstellar space, much like its twin before it, Voyager 1 (the only other human-made object to have travelled so far).

When DSS–43 upgrades are complete, the repairs will not only bolster our communications with Voyager 2 but will future-proof the facility for other upcoming missions, including future Mars missions.

Before that, though, perhaps the most pressing matter will be to reconnect ties with this famous pioneer from decades ago, as it sails ever further away, on its one-way trip to the stars.

UFOs Are Real — and You Were Never Supposed to See Them, Military Official Says

Remember those viral UFO videos you saw last year? The government would like you to forget them, please.

a grainy black and white video taken by the navy that shows two dark splotches that are thought to be ufos

A still from one of the notorious Navy UFO sighting videos.(Image: © To The Stars Academy of Arts and Science)

In December 2017 and March 2018, The New York Times released three allegedly declassified videos showing U.S. Navy pilots trailing some unidentified flying objects. The mystery crafts moved at hypersonic speeds, flying tens of thousands of feet above the Earth with no distinct wings, engines or visible signs of propulsion whatsoever. Were they flying saucers? Incredibly high-tech drones? The pilots had no idea — and, according to a recent statement from Navy intelligence officials, neither does the U.S. government.

In a statement delivered to the intelligence news website The Black Vault, Joseph Gradisher, a spokesperson for the Deputy Chief of Naval Operations for Information Warfare, announced that the Navy officially considers the craft in these three videos “unidentified aerial phenomena.” That means that the eerie videos are authentic — and that the objects, which were detected in restricted military training airspaces in 2004 and 2015, were not supposed to be there. The objects still have not been successfully identified as any known type of aircraft.

The UFO footage was also never cleared for public release, Gradisher told The Black Vault — meaning these are three unidentified phenomena you were never supposed to know about.

According to The Black Vault, the videos may have been improperly released by a former Pentagon employee who had applied for permission to share them across several government agencies as part of a database on unmanned aerial vehicles (UAV) he was allegedly compiling. The man received permission to share the videos for “[US Government] Use Only,” paperwork obtained by The Black Vault shows. However, Navy officials never declassified the footage for public release, Gradisher said.

What was the Navy trying to withhold, specifically? Only some very bizarre aerial acrobatics. In one incident filmed in 2004, for example, the unidentified objects “appeared suddenly at 80,000 feet, and then hurtled toward the sea, eventually stopping at 20,000 feet and hovering,” The New York Times wrote. “Then they either dropped out of radar range or shot straight back up.”

To be clear, nobody is saying that these mystery aircraft have anything to do with alien visitors; they simply can’t be identified or explained by current aeronautical knowledge. Comforted? Good — because this sort of thing probably happens way more often than we know.

New projects broaden the search for alien signals from space

A longer list of Earth-like planets, eavesdropping on radio waves and looking for laser light shows: All raise the chances of detecting E.T.

alienlife1600x600

Estimating the chance of getting a message from life beyond Earth, say within the next decade, isn’t easy. Even the best experts are reluctant to offer precise odds.

“Anybody who gave you a figure would be talking about religion, not science,” says Jill Tarter, the astronomer who has spent most of her life pursuing the quest to find signals from alien life.

And even if you did get an estimate for that probability, it wouldn’t mean much. (After all, the San Francisco 49ers had a 95 percent chance of winning the Super Bowl with under 8 minutes to go in the game — and still lost.)

But however small the probability of seeing a signal from E.T. is, those chances are soon going to be a lot better than they have been in the past.

Sure, after decades of listening, there is still no message. But with more data to sift through, and new technologies with superior search capabilities, odds of hearing from E.T. are rapidly improving. If the probability in the decade 2011–2021 were x percent, it’s going to be 1,000 times x in the following decade, says Andrew Siemion, director of the Berkeley SETI Research Center. (SETI stands for Search for Extra-Terrestrial Intelligence.)

The reason for E.T. optimism stems largely from several new projects in the works, enhanced with advanced methods for discerning an actual message hidden in the static of cosmic cacophony.

Siemion, speaking in Seattle on February 15 at the annual meeting of the American Association for the Advancement of Science, reported a new release of data from Breakthrough Listen, a major enterprise for recording radio signals from space. Now available for others to analyze, the data dump contains 2 petabytes of information (to store that much, you’d need 2,000 of today’s typical PCs with their puny 1 terabyte hard drives).

Tarter, chair emeritus for SETI Research at the pioneering SETI Institute, described new search projects in the works at the institute, including Laser SETI. It’s a plan to train 96 cameras at a dozen locations around the world to keep a constant vigil for “intelligent” optical signals from space.

Another key driver of increased optimism is the abundance of places to look for life. Thanks largely to the Kepler space telescope’s successful explorations, astronomers now know of thousands of stars possessing planets — and have spotted dozens of rocky, Earth-like planets orbiting their stars at a distance likely to be temperate enough for liquid water, a hopeful indicator of habitability.

And of course, it is still possible that alien life might be hiding closer to home. While it’s very unlikely that any intelligent life abides in our solar system, microbial biology might be viable on moons such as Enceladus (Saturn) and Europa (Jupiter). Robots equipped with tools to extract microorganisms from alien soil and conduct chemical analysis could search for life on site. In the meantime, land- or space-based telescopes might detect signs of biological activity in the atmosphere of distant planets. Certain combinations of molecules in the right ratio would be surefire signatures of life in action.

“The ultimate breakthrough in exoplanetary science will be the detection of a biosignature in the atmosphere of a rocky habitable-zone exoplanet,” astronomer Nikku Madhusudhan noted last year in the Annual Review of Astronomy and Astrophysics. “Defining a unique biosignature remains a theoretical challenge, but several candidate molecules have been suggested.”

No one molecule (not even oxygen) would be a definite sign of life. But multiple life-related molecules detected in the atmosphere of a planet with other suitable conditions (such as a comfy temperature) would be strong evidence. Under Earth-like conditions, various molecules, such as oxygen, ozone, methane, carbon dioxide, nitrous oxide and ammonia could be taken as indicators of biological activity.

“Though there is no single ideal molecule, the combination of multiple species (e.g., oxygen and methane) may be a potential biosignature under the given conditions,” wrote Madhusudhan, of the University of Cambridge in England. “In this regard, a detection of oxygen and methane and/or nitrous oxide along with liquid water on a habitable-zone planet, i.e., an almost exact Earth analog, may be a sure sign of life.”

exoplanetatmospheres

Astronomers studying planets orbiting stars other than the Sun learn about a variety of molecules in those planets’ atmospheres by probing different wavelengths of light, including visible light (optical) and ultraviolet and infrared radiation. Scientists propose that certain combinations of molecules, such as water (H2O) and methane (CH4), could be signs of lifeKnowable Magazine after N. Madhusudhan/AR Astronomy and Astrophysics 2019

Seeking techno-signals

Finding primitive extraterrestrial life would be front-page news (or set a record for clicks), but the grand prize is reserved for the “I” in SETI — intelligent life. SETI searches seek signs of technology produced by extraterrestrial intelligence, most likely in the form of “unnatural” radio waves.

In fact, an alien looking for life in the cosmos might very well spot Earth as inhabited by exactly that method. In the 1990s, Carl Sagan and colleagues took advantage of the Galileo spacecraft’s pass by Earth to probe our planet for telltale signals of our existence. The giveaway was narrow-band radio emissions (abundant signaling at a single radio frequency).

“That as far as we know is an unmistakable indicator of technology, and an unmistakable indicator of life,” Siemion said at the AAAS meeting. “And indeed it is the most detectable signature of life on this planet as viewed from a distant vantage point.”

For now, Earth-based radio telescopes listening to the cosmos might hear a deliberate message, but couldn’t pick up TV shows or other radio-wave “leakage” from alien civilizations. But the Next Generation Very Large Array, now in the planning stage, would have the power to receive such unintentional communication, at least from nearby stars.

Perhaps alien civilizations may make more use of lasers than radio, though, which makes the prospect of Laser SETI appealing. But whether patterns are found in the radio or optical region of the electromagnetic spectrum doesn’t matter — such patterns could reveal intelligent activity regardless of their purpose, Siemion pointed out.

“We simply look for compression of electromagnetic energy in time or in frequency or some kind of modulation that is inconsistent with the astrophysical background or the instrumental background and consistent with something that technology could produce,” he said. “So it doesn’t matter if it’s a laser communication system being used to communicate with a spacecraft in some exoplanet system or it’s a giant laser light show that some very advanced civilization produced for the amusement of all the life in their system.”

Gngvlaantennamap

A map shows the planned spiral-shaped array of 244 fixed radio antennas, most nearly 60 feet across, that will make up the Next Generation Very Large Array telescope. Centered in the US Southwest and Mexico with arms as far as Hawaii and the Caribbean, the ngVLA will be sensitive enough to detect radio wave “leakage” (unintentional signals, such as TV shows) from the nearest stars.NRAO

In any event, receiving a message would be a monumental revelation about the viability of technological civilizations. Nobody knows whether a society that has developed advanced technology can long survive.

“The lifetime of a technological civilization … is a very difficult thing to predict,” said Siemion. “And of course, looking around at our own civilization you have reason to question what that term might be.”

On the other hand, a signal from space would almost certainly be from a civilization that has existed much longer than ours. (Otherwise the likelihood of listening in at exactly the right time would be prohibitively small.) So merely receiving a message might be considered hope that civilization on Earth might not be doomed after all.

Success in receiving a message raises other issues. For one thing, it’s a real possibility that an alien message is clearly an attempt to communicate, but in a language that no earthling could understand. And understood or not, a message received suggests the need to consider a reply. SETI researchers have long agreed that if a signal is detected, no response would be made until a global consensus had been reached on who will speak for Earth and what they would say. But that agreement is totally unenforceable, Tarter pointed out, and nobody has any idea about how to reach a global consensus on anything. (Perhaps the proper reply would just be “HELP!”)

Still, contemplating a response is for the moment a lesser priority than finding a message in the first place. And that might require help from nonhuman intelligence right here on Earth in the form of advanced computers. Recent developments in artificial intelligence research should soon make machine learning an effective tool in the E.T. search, Tarter said at the AAAS meeting.

“The ability to use machine learning to help us find signals in noise I think is really exciting,” she said. “Historically we’ve asked a machine to tell us if a particular pattern in frequency and time could be found. But now we’re on the brink of being able to say to the machine, ‘Are there any patterns in there?’”

So it’s possible that an artificially intelligent computer might be the first earthling to discern a message from an extraterrestrial. But then we would have to wonder, would a smart machine detecting a message bother to tell us? That might depend on whom (or what) the message was from.

“I think there’s something particularly romantic,” said Siemion, “about the idea of machine learning and artificial intelligence looking for extraterrestrial intelligence which itself might be artificially intelligent.”

NASA SPACECRAFT RECOVERS FROM GLITCH 11.5 BILLION MILES FROM EARTH

Interstellar Glitch

NASA’s Voyager 2, initially launched in 1977 to study our star system’s outer planets, is currently in interstellar space billions of miles from Earth. In January, the probe experienced a serious glitch that affected a host of crucial scientific instruments.

But luckily, the record-breaking spacecraft is back online.

“The five operating science instruments, which were turned off by the spacecraft’s fault protection routine, are back on and returning normal science data,” NASA’s Jet Propulsion Lab wrote in an update.

Power Supply

Voyager 2 currently is racing through interstellar space at a distance of about 11.5 billion miles (18.5 billion kilometers) from Earth. That means any communications take 17 whole hours to reach it, according to NASA — and another 17 to make it back. Understandably, that’s making the task of fixing the spacecraft’s software very tricky.

The glitch was caused by a “fault protection software routine” after Voyager 2 failed to calibrate itself by spinning around its axis on January 25. Two systems were left running at relatively high levels of power, causing the spacecraft to “overdraw its available power supply.”

Bye, Sun

In December 2018, 40 years after it was launched into space, Voyager 2 became the second human-made object to exit the heliosphere, the Sun’s protective bubble around the Solar System. Its twin spacecraft Voyager 1 was the first, reaching interstellar space in 2012.

And Voyager 1 is glad to have its twin back online, the space agency joked.

“All right now, baby, it’s all right now! My twin, Voyager 2, is back to normal operations,” tweeted NASA’s official Voyager account.

Asteroid almost as big as Mount Everest to pass Earth next month, NASA says

A gigantic asteroid almost as large as Mount Everest is zooming toward Earth next month, but NASA says not to worry — it’s not expected to collide with our planet.

The space rock is called 52768 (1998 IR2) and was first seen 22 years ago. According to the space agency, early in the morning on Wednesday, April 29, it will pass within 3,908,791 miles of Earth, moving at 19,461 miles per hour.

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“[The asteroid’s discovery comes] on the heels of last month’s installation of new state-of-the-art computing and data analysis hardware that speeds our search for near-Earth objects,” said NEAT Project Manager Steven Pravdo of JPL in a statement at the time of the asteroid’s discovery. “This shows that our efforts to find near-Earth objects are paying off.”

An illustration shows a rocket approaching an asteroid that's drifted too close to Earth. A scout probe orbits nearby.

An illustration shows a rocket approaching an asteroid that’s drifted too close to Earth. A scout probe orbits nearby. (Christine Daniloff, MIT)

Although the asteroid, which is between 1 and 2.5 miles wide, is classified as potentially hazardous because of how close it will be to Earth’s orbit, NASA scientists have not put it on the agency’s list of potential future impact events.

“Our goal is to discover and track all the potentially dangerous asteroids and comets long before they are likely to approach Earth,” said NEAT Principal Investigator Eleanor Helin.

NASA catches amazing glimpse of new black hole

NASA students discovered a new black hole 30,000 light years away.

In November 2019, the student-built Regolith X-Ray Imaging Spectrometer (REXIS) onboard NASA’s OSIRIS-REx spacecraft detected a newly flaring black hole in the constellation Columba while making observations off the limb of asteroid Bennu.

“Our initial checks showed no previously cataloged object in that position in space,” Branden Allen, a Harvard research scientist and student supervisor who first spotted the source in the REXIS data, said in a statement.

According to NASA, the glowing object turned out to be a newly flaring black hole X-ray binary.

An instrument developed by students at MIT and Harvard picked up a flare of X-rays from a black hole that is now named MAXI J0637-430.

An instrument developed by students at MIT and Harvard picked up a flare of X-rays from a black hole that is now named MAXI J0637-430. (NASA)

“Detecting this X-ray burst is a proud moment for the REXIS team. It means our instrument is performing as expected and to the level required of NASA science instruments,” said Madeline Lambert, an MIT graduate student who designed the instrument’s command sequences that revealed the black hole, in a statement.

X-ray blasts can only be seen from space because Earth’s protective atmosphere shields our planet from X-rays.

The purpose of the REXIS instrument is to train the next generation of scientists and engineers in the creation of and operation of spaceflight hardware, NASA said.

“We set out to train students how to build and operate space instruments,” said MIT professor Richard Binzel, instrument scientist for the REXIS student experiment. “It turns out, the greatest lesson is to always be open to discovering the unexpected.”

Six cosmic catastrophes that could wipe out life on Earth

If you ask yourself what the biggest threat to human existence is you’d probably think of nuclear war, global warming or a large-scale pandemic disease. But assuming we can overcome such challenges, are we really safe?

Living on our blue little planet seems safe until you are aware of what lurks in space. The following cosmic disasters are just a few ways humanity could be severely endangered or even wiped out. Happy reading!

1. High energy solar flare

Our sun is not as peaceful a star as one might initially think. It creates strong magnetic fields that generate impressive sun spots, sometimes many times larger than Earth. It also ejects a stream of particles and radiation – the solar wind. If kept in check by Earth’s magnetic field, this wind can cause beautiful northern and southern lights. But when it becomes stronger, it can also influence radio communication or cause power outages.

The most powerful magnetic solar storm documented hit Earth in 1859. The incident, called the Carrington Event, caused huge interference with rather small scale electronic equipment. Such events must have happened several times in the past, too, with humans surviving.

But only in recent years have we become entirely dependent on electronic equipment. The truth is we would suffer greatly if we underestimate the dangers of a possible Carrington or even more powerful event. Even though this would not wipe out humanity instantly, it would represent an immense challenge. There would be no electricity, heating, air conditioning, GPS or internet – food and medicines would go bad.

2. Asteroid impact

We are now well aware of the dangers asteroids could pose to humanity – they are, after all, thought to have contributed to the extinction of the dinosaurs. Recent research has made us aware of the large host of space rocks in our solar system that could pose danger.

Dangerous impact. Don Davis/NASA

We are at the starting point of envisaging and developing systems for protecting us against some of the smaller asteroids that could strike us. But against the bigger and rarer ones we are quite helpless. While they would not always destroy Earth or even make it uninhabitable, they could wipe out humanity by causing enormous tsunamis, fires and other natural disasters.

3. Expanding sun

Where the previous cosmic dangers occur at the roll of a dice with a given probability, we know for certain that our sun will end its life in 7.72 billion years. At this point, it will throw off its outer atmosphere to form a planetary nebula, ending up as a stellar remnant know as a “white dwarf”.

But humanity will not experience these final stages. As the sun becomes older, it will become cooler and larger. By the time it becomes a stellar giant it will be big enough to engulf both Mercury and Venus. Earth might seem safe at this point, but the sun will also create an extremely strong solar wind that will slow down the Earth. As a result, in about 7.59 billion years, our planet will spiral into the outer layers of the hugely expanded dying star and melt away forever.

4. Local gamma ray burst

Extremely powerful outbursts of energy called gamma ray bursts can be caused by binary star systems (two stars orbiting a common centre) and supernovas (exploding stars). These energy bursts are extremely powerful because they focus their energy into a narrow beam lasting no longer than seconds or minutes. The resulting radiation from one could damage and destroy our ozone layer, leaving life vulnerable to the sun’s harsh UV radiation.

Astronomers have discovered a star system – WR 104 – that could host such an event. WR 104 is about 5,200-7,500 light years away, which is not far enough to be safe. And we can only guess when the burst will happen. Luckily, there is the possibility that the beam could miss us entirely when it does.

5. Nearby supernovas

Supernova explosions, which take place when a star has reached the end of its life, occur on average once or twice every 100 years in our Milky Way. They are more likely to occur closer to the dense centre of the Milky Way and we are about two-thirds of the way from the middle – not too bad.

SN 1994D (bright spot on the lower left), a type Ia supernova in the NGC 4526 galaxy. NASA/ESA, CC BY-SA

So can we expect a nearby supernova anytime soon? The star Betelgeuse – a red super giant nearing the end of its life – in the constellation of Orion is just 460-650 light years away. It could become a supernova now or in the next million years. Luckily, astronomers have estimated that a supernova would need to be within at least 50 light years of us for its radiation to damage our ozone layer. So it seems this particular star shouldn’t be too much of a concern.

6. Moving stars

Meanwhile, a wandering star on its path through the Milky Way might come so close to our sun that it would interact with the rocky “Oort cloud” at the edge of the solar system, which is the source of our comets. This might lead to an increased chance of a huge comet hurtling to Earth. Another roll of the dice.

The sun itself follows a path through the Milky Way that takes us through more or less dense patches of interstellar gas. Currently we are within a less dense bubble created by a supernova. The sun’s wind and solar magnetic field help create a bubble-like region surrounding our solar system – the heliosphere – which shields us from interacting with the interstellar medium. When we leave this region in 20,000 to 50,000 years (depending on current observations and models), our heliosphere could be less effective, exposing Earth. We would possibly encounter increased climate change making life more challenging for humanity – if not impossible.

And life goes on…

The end of humanity on Earth is a given. But this is not something to make us crawl under a table. It is something that we cannot change, similar to our lives having a definite start and end. This is what defines us and makes us realise that the only thing we can do is make the most of our time on Earth. Especially when we know that Earth needs a careful balance to sustain humanity.

All the above scenarios harbour possible destruction, but in every instance they also offer beauty and wonder. In many cases, they produce what allowed us to be created. So rather than looking into the night sky and wondering what will kill us next, we should marvel at the depth of space, the wonders therein and the sublime nature of the universe. Be inspired by space. It offers future and meaning.

Asteroid warning: NASA tracks a 4KM killer rock on approach – Could end human civilization

AN ASTEROID capable of ending human civilization if it hits will approach our planet in April, NASA’s asteroid trackers have confirmed.

The asteroid is being watched by NASA’s automated tracking systems at the Center for Near Earth Object Studies in California, US. The asteroid has been officially called 52768 (1998 OR2) and is estimated measure up 2.5 miles (4.1km) across.

An object this big could potentially spell the end of the human race if it strikes the planet.

NASA estimates the rock is heading our way at speeds of about 8.7km per second or 19,461mph (31,320kmh).At this rate, the asteroid will close-in on Earth on April 29.

When this happens, NASA said the asteroid will make a “close approach” to our planet.

According to the Planetary Society, an asteroid bigger than 0.6 miles (1km) across is big enough to threaten global destruction.PROMOTED STORY

Asteroid warning: Monster space rock hitting Earth

Asteroid warning: NASA is tracking the movement of a 4.1km space rock (Image: GETTY)

Asteroid warning: Large space rock over Earth

Asteroid warning: NASA said the space rock will make a close approach in April (Image: GETTY)

Astronomers estimate such objects have a one in 50,000 chance of hitting Earth every 100 years.

The Planetary Society lists the following impacts: “A crater of 10km or more: global devastation and possible collapse of civilisation.”

Dr Bruce Betts from the international group of astronomers said: “Small asteroids – few metres – hit frequently and burn up in the atmosphere and do little damage.

“Chelyabinsk size asteroids – about 20m that hit in 2013 – create shock waves that shatter windows and cause injuries.

“Tunguska sized – about 40m that hit Siberia in 1908 – could completely destroy a city or create a tsunami.

“Larger asteroids that hit on average less often could cause regional destruction.

“Even larger asteroids that hit even less frequently could cause a global catastrophe.”

The destructive potential of space rocks this big was also outlined in a 2018 report published by the US National Science and Technology Council.

Even larger asteroids that hit even less frequently could cause a global catastrophe

Dr Bruce Betts, The Planetary Society

The National Near-Earth Object Preparedness Strategy reads: “Objects close to and larger than one kilometre can cause damage on a global scale.

“They can trigger earthquakes, tsunamis, and other secondary effects that extend far beyond the immediate impact area.”

For comparison, the asteroid that is believed to have killed the dinosaurs measured about six miles (10km) across.

Asteroid facts: Differences between space rocks

Asteroid facts: The differences between asteroids, comets and meteors (Image: EXPRESS/GETTY)

Asteroid warning: Space rock hitting Earth

Asteroid warning: The asteroid could end civilisation if it hits (Image: GETTY)

NASA estimates Asteroid 1998 OR2 measures somewhere between 0.9 miles and 2.54 miles (1.5km and 4.1km) in diameter.

The space rock was spotted flying around the Sun in 1987 and NASA confirmed it’s orbit on June 30, 1987.

Astronomers have classed the rock as a “potentially hazardous” NEO or near-Earth object.

But just how close does NASA expect the asteroid to come to Earth next month?

At its closest, the space rock will approach our planet from about 0.04205 astronomical units.

One astronomical unit is the average distance from our planet to the Sun – about 93 million miles (149.6 million km).

Asteroid OR2 will drastically cut this down to just 3.9 million miles (6.29 million km) on April 29.

In other words, the space rock is expected to miss us by about 16.36 times the distance from Earth to the Moon.

Dr Betts said: “There are a few asteroids that currently are known to have a low probability of hitting Earth in tens to hundreds of years.

“For example, one of the highest probabilities currently is an approximately 37m diameter asteroid called 2000 SG344 that has a 1 in 1100 chance of impact in 2071.

“But these always are based on asteroid observations that have uncertainties in them.”

Scientists claim they’ve discovered first extraterrestrial protein in meteorite that fell to Earth 30 years ago

Scientists say they have discovered the first known protein that originated in space, located in a meteorite that fell to Earth 30 years ago.

The meteorite, known as Acfer 086, hit Algeria 30 years ago and contains the protein hemolithin. Inside the hemolithin are iron and lithium, two building blocks for life, the researchers said in the study located on the arXiv repository.

“Analysis of the complete spectrum of isotopes associated with each molecular fragment shows 2H enhancements above terrestrial averaging 25,700 parts per thousand (sigma = 3,500, n=15), confirming extra-terrestrial origin and hence the existence of this molecule within the asteroid parent body of the CV3 meteorite class,” the study’s abstract states. “The molecule is tipped by an iron-oxygen-iron grouping that in other terrestrial contexts has been proposed to be capable of absorbing photons and splitting water into hydroxyl and hydrogen moieties.”

Acfer 086 was discovered in 1990 and has a mass of 173 grams, according to The Meteorological Society.

In an interview with ScienceAlert, astronomer and chemist Chenoa Tremblay said it’s believed that proteins are “likely to exist in space,” but this would be the first evidence of such.

“So we’re pretty sure that proteins are likely to exist in space,” Tremblay, who was not involved in the study, told ScienceAlert. “But if we can actually start finding evidence of their existence, and what some of the structures and the common structures might be, I think that’s really interesting and exciting.”

Because the hemolithin in Acfer 086 has a similar structure to proteins on Earth and its ratio of hydrogen to isotope deterium is similar to that seen in the Oort cloud, it’s believed it could have formed nearly 4.6 billion years ago, in the proto-solar disk, the Daily Mail reports.

A study was published in October 2019 that suggested the second interstellar object ever discovered, Comet 2I/Borisov, could be carrying water on it from beyond the solar system, releasing water vapor on its journey.

A separate study published in 2018 suggested that cometlike objects could be “ferrying” microbial life across thousands of light-years.

SETI search of interstellar Comet Borisov finds no sign of alien ‘technosignatures’

NASA's Hubble Space Telescope captured this view of the interstellar object Comet 2I/Borisov on Oct. 12, 2019.

NASA’s Hubble Space Telescope captured this view of the interstellar object Comet 2I/Borisov on Oct. 12, 2019.(Image: © NASA/ESA/D. Jewitt (UCLA))

Our solar system’s second known interstellar visitor appears to be keeping quiet, just like the first.

The Breakthrough Listen SETI (search for extraterrestrial intelligence) project has scanned the interstellar Comet Borisov for “technosignatures” but come up empty so far, scientists announced today (Feb. 14). 

Breakthrough Listen also encountered radio silence during an earlier investigation of the mysterious ‘Oumuamua, the first confirmed interstellar object ever spotted in our solar system. The null results may be disappointing to alien enthusiasts out there, but they’re valuable all the same, project team members said.

“If interstellar travel is possible, which we don’t know, and if other civilizations are out there, which we don’t know, and if they are motivated to build an interstellar probe, then some fraction greater than zero of the objects that are out there are artificial interstellar devices,” Steve Croft, a research astronomer with Breakthrough Listen and the Berkeley SETI Research Center at the University of California, Berkeley, said in a statement.

“Just as we do with our measurements of transmitters on extrasolar planets, we want to put a limit on what that number is,” Croft added.

It’s also worth noting that SETI silence does not necessarily guarantee a natural origin for Borisov and ‘Oumuamua. It’s possible, for example, that they’re transmitting a type of signal that we’re not looking for, or that they’re defunct alien craft.

Indeed, a possible artificial origin has been invoked by some scientists — notably, Avi Loeb, the Harvard astronomy department chair — to explain ‘Oumuamua’s very weird combination of characteristics. Loeb has suggested that ‘Oumuamua, which looped around the sun in September 2017, might be a light-sailing alien spacecraft. (Comet Borisov made its closest approach to our star in December 2019.)

The Borisov news is part of a huge data dump by Breakthrough Listen, a $100 million life-hunting effort  established in 2016 by billionaire Yuri Milner. During a news conference today at the annual meeting of the American Association for the Advancement of Science in Seattle, project team members announced the release of nearly 2 petabytes of SETI data, much of which astronomers have not yet had a chance to study in detail. 

Breakthrough Listen team members said the newly released information represents the most comprehensive survey to date of radio emissions from the plane of our Milky Way galaxy and the region around its central supermassive black hole

“The galactic center is the subject of a very specific and concerted campaign with all of our facilities, because we are in unanimous agreement that that region is the most interesting part of the Milky Way galaxy,” Breakthrough Listen Principal Investigator Andrew Siemion, of the University of California, Berkeley, said in the same statement. 

“If an advanced civilization anywhere in the Milky Way wanted to put a beacon somewhere . . . the galactic center would be a good place to do it,” he added. “It is extraordinarily energetic, so one could imagine that if an advanced civilization wanted to harness a lot of energy, they might somehow use the supermassive black hole that is at the center of the Milky Way galaxy.”

And you have a chance to help turn up evidence of such advanced creatures, if any are there to be found: Breakthrough Listen is inviting the public to help analyze this trove of SETI data.

“Since Breakthrough Listen’s initial data release last year, we have doubled what is available to the public,” Matt Lebofsky, Breakthrough Listen lead system administrator, said in the same statement, referring to a petabyte-size data dump in June 2019. “It is our hope that these data sets will reveal something new and interesting, be it other intelligent life in the universe or an as-yet-undiscovered natural astronomical phenomenon.”

You can learn about how to participate here.

About half of the new data comes from the Parkes radio telescope in New South Wales, Australia, team members said. The rest was collected by the big radio dish at West Virginia’s Green Bank Observatory and the Automated Planet Finder, an optical telescope located at Lick Observatory in California. (SETI signals don’t necessarily have to be in the radio spectrum, after all; laser flashes could betray the presence of intelligent aliens as well.)

Also today, the SETI Institute in Mountain View, California, and the National Radio Astronomy Observatory (NRAO) announced an agreement to start installing technosignature-hunting gear on NRAO dishes. 

So, the search for E.T. continues to ramp up, which is just what Milner wants.

“For the whole of human history, we had a limited amount of data to search for life beyond Earth. So, all we could do was speculate,” Milner said in the same statement. “Now, as we are getting a lot of data, we can do real science and, with making this data available to the general public, so can anyone who wants to know the answer to this deep question.”