Lightning strikes will more than double in Arctic as climate warms.

 

In 2019, the National Weather Service in Alaska reported spotting the first-known lightning strikes within 300 miles of the North Pole. Lightning strikes are almost unheard of above the Arctic Circle, but scientists led by researchers at the University of California, Irvine have published new research in the journal Nature Climate Change detailing how Arctic lightning strikes stand to increase by about 100 percent over northern lands by the end of the century as the climate continues warming. 

"We projected how lightning in high-latitude boreal forests and Arctic tundra regions will change across North America and Eurasia," said Yang Chen, a research scientist in the UCI Department of Earth System Science who led the new work. "The size of the lightning response surprised us because expected changes at mid-latitudes are much smaller."
The finding offers a glimpse into the changes that're in store for the Arctic as the planet continues warming; it suggests Arctic weather reports during summertime will be closer to those seen today far to the south, where lightning storms are more common.
James Randerson, a professor in UCI's Department of Earth System Science who co-authored the study, was part of a NASA-led field campaign that studied wildfire occurrence in Alaska during 2015, which was a extreme year for wildfires in the state. "2015 was an exceptional fire year because of a record number of fire starts," Randerson said. "One thing that got us thinking was that lightning was responsible for the record-breaking number of fires."
This led Chen to look at over-twenty-year-old NASA satellite data on lighting strikes in northern regions, and construct a relationship between the flash rate and climatic factors. By using future climate projections from multiple models used by the United Nations, the team estimated a significant increase in lightning strikes as a result of increases in atmospheric convection and more intense thunderstorms.
A lightning strike bump could open a Pandora's box of related troubles. Fires, Randerson explained, burn away short grasses, mosses, and shrubs that are important components of Arctic tundra ecosystems. Such plants cover much of the landscape, and one thing they do is keep the seeds of trees from taking root in the soil. After a fire burns away low-lying plants, however, seeds from trees can more easily grow on bare soil, allowing forests stands to expand north. Evergreen forests will replace what's typically a snow-covered landscape; snow's white hue reflects sunlight back out into space, but darker forests absorb solar energy, helping warm the region even further.
And there's more trouble: more fires mean more permafrost—perennially frozen soil that defines much of the Arctic landscape—will melt as the fires strip away protective insulative layers of moss and dead organic matter that keep soils cool. Permafrost stores a lot of organic carbon that, if melted out of the ice, will convert to greenhouse gases carbon dioxide and methane, which, when released, will drive even more warming.
The lighting finding comes of the heels of another study that, led by Randerson, published in the Journal of Geophysical Research on Monday, April 5 describes how amplified Arctic warming and the melting of the Greenland ice sheet will scramble food webs in the surrounding oceans.
Now, Chen and Randerson say, scientists need to start paying more attention to the frequency of Arctic lightning strikes so they can gauge how the story unfolds in the coming decades.
"This phenomenon is very sporadic, and it's very difficult to measure accurately over long time periods," said Randerson. "It's so rare to have lightning above the Arctic Circle." Their results, he hopes, will galvanize calls for new satellite missions that can monitor Arctic and boreal latitudes for lightning strikes and the fires they might ignite.
Back in 2019, the National Weather Service in Alaska released a special announcement about the North Pole lightning strikes. Such announcements, however, may struggle to make headlines by the end of the century.

Nasa drops Mars helicopter Ingenuity onto surface.

 

Nasa’s Perseverance rover has dropped Ingenuity, the helicopter that will conduct the first controlled flight on another planet, onto the surface of Mars.
The helicopter fell four inches from the belly of Perseverance onto Mars.
It means that the helicopter is now looking after itself: heating and powering itself, which includes gathering solar energy from panels attached to its body. Temperatures through the night can drop as low as -54 degrees celsius, and an on-board heater aims to ensure that its battery and other components are protected from any damage.
At some point after 11 April, and when preparations are over, Ingenuity will take off for the first ever powered flight on any other planet. It could do so as many as five times over the following month, Nasa said – before
its test period is over and it will shut down to lie on the surface forever.

While the four inches from the bottom of the rover to the surface of Mars might seem small, they were among the most critical parts of the mission. They were the end of a process that began with Ingenuity turning around so that it was lying flat to drop onto the surface, and it was key that Ingenuity made it through safely to ensure it could take off.

Nasa also noted that those four inches came at the end of a 293 million mile journey that took the helicopter and its rover from Earth to Mars.

The space agency has not said exactly when the helicopter will take off, only that it will happen “no earlier than” 11 April. Before that happens, Nasa will hae to ensure that its battery is recharging properly, its motors and sensors are working as expected, and unlocking the rotor blades that will carry it.

The first flight will see the helicopter take off, hover a few feet above the ground for half a minute, and then land back down again.

That will be a major test of the technology that has been developed to ensure that Ingenuity can fly safely despite the very thin atmosphere on Mars. It will also represent the first time any object has conducted a power flight on another planet.

If that test is successful, the team will continue to fly further and higher over the 30-day mission period.

Nasa says that Ingenuity’s testing is intended primarily as a technology demonstration, and a proof of the work done to ensure it can fly. It will not conduct any research as it does so.

Perseverance will be at a safe distance throughout that testing, continuing its scientific work.

Scientists detect world's coldest cloud hovering over Pacific Ocean.

 

Storms near Nauru on Dec. 29, 20118 captured in infrared by an orbiting satellite. The cold parts of the clouds are in purple and the warm Pacific Ocean is in orange. (Image credit: National Centre for Earth Observation)
A severe thunderstorm cloud that formed over the Pacific Ocean in 2018 reached the coldest temperatures ever recorded, according to a new study.
The very top of the storm cloud reached a bone-chilling minus 167.8 degrees Fahrenheit (minus 111 degrees Celsius), colder than any storm cloud measured before. Thunderstorms and tropical cyclones, a circular low-pressure storm, can reach very high altitudes — up to 11 miles (18 kilometers) from the ground  — where the air is much cooler, according to a statement from the U.K.'s National Center for Earth Observation.
But this new temperature is on another level. The top of the storm cloud was about  86 F (30 C) colder than typical storm clouds, according to the statement. The beast of a storm loomed about 249 miles (400 km) south of Nauru in the Southwest Pacific on Dec. 29, 2018, and its clouds' temperature was picked up by an infrared sensor aboard the U.S.'s NOAA-20 satellite orbiting the planet.

Storms typically spread out into an anvil-like shape when they reach the top of the troposphere, the lowest layer of Earth's atmosphere. But if a storm has a lot of energy, it will shoot into the next layer, the stratosphere. This phenomenon, known as an "overshooting top," pushes storm clouds to very high altitudes, where it's bitterly cold.

Overshooting tops are "reasonably common," lead author Simon Proud, a research fellow at the National Centre for Earth Observation and at Oxford University. Typically, an overshooting top cools by about 12.6 F (7 C) for every kilometer it rises in the stratosphere, he said.

But this storm was particularly extreme. "This storm achieved an unprecedented temperature that pushes the limits of what current satellite sensors are capable of measuring," Proud said in the statement. "We found that these really cold temperatures seem to be becoming more common."

In the last three years, scientists have logged the same number of extremely cold temperatures in clouds as they did in the 13 years before that, he added. "This is important, as thunderstorms with colder clouds tend to be more extreme, and more hazardous to people on the ground due to hail, lightning and wind."

This particular storm may have been energized by a combination of very warm water in the region and eastward-moving wind, according to the BBC. However, it's not clear why these colder temperatures in storm clouds are becoming more common. 

"We now need to understand if this increase is due to our changing climate or whether it is due to a 'perfect storm' of weather conditions producing outbreaks of extreme thunderstorms in the last few years," Proud said.

Mysterious Interstellar Visitor May Be the Most Pristine Comet Ever Found.

New observations with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) indicate that the rogue comet 2I/Borisov, which is only the second and most recently detected interstellar visitor to our Solar System, is one of the most pristine ever observed. Astronomers suspect that the comet most likely never passed close to a star, making it an undisturbed relic of the cloud of gas and dust it formed from.

2I/Borisov was discovered by amateur astronomer Gennady Borisov in August 2019 and was confirmed to have come from beyond the Solar System a few weeks later. “2I/Borisov could represent the first truly pristine comet ever observed,” says Stefano Bagnulo of the Armagh Observatory and Planetarium, Northern Ireland, UK, who led the new study published today in Nature Communications. The team believes that the comet had never passed close to any star before it flew by the Sun in 2019.

New observations with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) indicate that the rogue comet 2I/Borisov, which is only the second and most recently detected interstellar visitor to our Solar System, is one of the most pristine ever observed. This video summarizes new findings on this mysterious alien visitor. Credit: ESO

Bagnulo and his colleagues used the FORS2 instrument on ESO’s VLT, located in northern Chile, to study 2I/Borisov in detail using a technique called polarimetry.^[1] Since this technique is regularly used to study comets and other small bodies of our Solar System, this allowed the team to compare the interstellar visitor with our local comets.

The team found that 2I/Borisov has polarimetric properties distinct from those of Solar System comets, with the exception of Hale–Bopp. Comet Hale–Bopp received much public interest in the late 1990s as a result of being easily visible to the naked eye, and also because it was one of the most pristine comets astronomers had ever seen. Prior to its most recent passage, Hale–Bopp is thought to have passed by our Sun only once and had therefore barely been affected by solar wind and radiation. This means it was pristine, having a composition very similar to that of the cloud of gas and dust it — and the rest of the Solar System — formed from some 4.5 billion years ago.

This image was taken with the FORS2 instrument on ESO’s Very Large Telescope in late 2019, when comet 2I/Borisov passed near the Sun. Since the comet was traveling at breakneck speed, around 175,000 kilometers per hour, the background stars appeared as streaks of light as the telescope followed the comet’s trajectory. The colors in these streaks give the image some disco flair and are the result of combining observations in different wavelength bands, highlighted by the various colors in this composite image. Credit: ESO/O. Hainaut

By analyzing the polarisation together with the color of the comet to gather clues on its composition, the team concluded that 2I/Borisov is in fact even more pristine than Hale–Bopp. This means it carries untarnished signatures of the cloud of gas and dust it formed from.

“The fact that the two comets are remarkably similar suggests that the environment in which 2I/Borisov originated is not so different in composition from the environment in the early Solar System,” says Alberto Cellino, a co-author of the study, from the Astrophysical Observatory of Torino, National Institute for Astrophysics (INAF), Italy.

Olivier Hainaut, an astronomer at ESO in Germany who studies comets and other near-Earth objects but was not involved in this new study, agrees. “The main result — that 2I/Borisov is not like any other comet except Hale–Bopp — is very strong,” he says, adding that “it is very plausible they formed in very similar conditions.”

“The arrival of 2I/Borisov from interstellar space represented the first opportunity to study the composition of a comet from another planetary system and check if the material that comes from this comet is somehow different from our native variety,” explains Ludmilla Kolokolova, of the University of Maryland in the US, who was involved in the Nature Communications research.
Bagnulo hopes astronomers will have another, even better, opportunity to study a rogue comet in detail before the end of the decade. “ESA is planning to launch Comet Interceptor in 2029, which will have the capability of reaching another visiting interstellar object, if one on a suitable trajectory is discovered,” he says, referring to an upcoming mission by the European Space Agency.

Even without a space mission, astronomers can use Earth’s many telescopes to gain insight into the different properties of rogue comets like 2I/Borisov. “Imagine how lucky we were that a comet from a system light-years away simply took a trip to our doorstep by chance,” says Bin Yang, an astronomer at ESO in Chile, who also took advantage of 2I/Borisov’s passage through our Solar System to study this mysterious comet. Her team’s results are published in Nature Astronomy.

Yang and her team used data from the Atacama Large Millimeter/submillimeter Array (ALMA), in which ESO is a partner, as well as from ESO’s VLT, to study 2I/Borisov’s dust grains to gather clues about the comet’s birth and conditions in its home system.

They discovered that 2I/Borisov’s coma — an envelope of dust surrounding the main body of the comet — contains compact pebbles, grains about one millimeter in size or larger. In addition, they found that the relative amounts of carbon monoxide and water in the comet changed drastically as it neared the Sun. The team, which also includes Olivier Hainaut, says this indicates that the comet is made up of materials that formed in different places in its planetary system.
The observations by Yang and her team suggest that matter in 2I/Borisov’s planetary home was mixed from near its star to further out, perhaps because of the existence of giant planets, whose strong gravity stirs material in the system. Astronomers believe that a similar process occurred early in the life of our Solar System.
While 2I/Borisov was the first rogue comet to pass by the Sun, it was not the first interstellar visitor. The first interstellar object to have been observed passing by our Solar System was ʻOumuamua, another object studied with ESO’s VLT back in 2017. Originally classified as a comet, ʻOumuamua was later reclassified as an asteroid as it lacked a coma.

1. Polarimetry is a technique to measure the polarisation of light. Light becomes polarized, for example, when it goes through certain filters, like the lenses of polarized sunglasses or cometary material. By studying the properties of sunlight polarized by a comet’s dust, researchers can gain insights into the physics and chemistry of comets..

Why One Side of Earth Is Rapidly Getting Colder Than the Other

 In a new study, scientists from the University of Oslo say one side of Earth’s interior is losing heat much faster than the other side—and the culprit is practically as old as time.

The research, published in Geophysical Research Letters, uses computer models of the last 400 million years to calculate how “insulated” each hemisphere was by continental mass, which is a key quality that holds heat inside instead of releasing it. The pattern goes all the way back to Pangaea.
Earth has a red hot liquid interior that warms the entire planet from inside. It spins, too, generating both gravity and Earth’s magnetic field. This holds our protective atmosphere close to Earth’s surface.
Over the extremely long term, this interior will continue to cool until Earth is more like Mars. The surprise in the new study is how unevenly the heat is dissipating, but the reason makes intuitive sense: Parts of Earth have been insulated by more landmass, creating something of a Thermos layer that traps heat.

This contrasts with how Earth loses most of its heat: “Earth’s thermal evolution is largely controlled by the rate of heat loss through the oceanic lithosphere,” the study authors write. Why is this the site of the greatest loss? For that, we need a quick-and-dirty run-through of continental drift. 

Earth’s mantle is like a convection oven that powers a treadmill. Every day, seafloor surface moves a tiny bit; new seafloor is born from the magma that erupts at the continental divide, while old seafloor is smashed and melted beneath existing continental landmass.

To study how Earth’s interior heat behaves, the scientists built a model that divides Earth into African and Pacific hemispheres, then divides Earth’s entire surface into a grid by half degrees latitude and longitude.

The scientists combined several previous models for things like seafloor age and continental positions during the last 400 million years. Then, the team crunched the numbers for how much heat each grid cell contains over its long life. This paved the way to calculate the rate of cooling overall, where the researchers found the Pacific side has cooled much faster.

 Accumulated mantle heat loss (oceanic + continental) over the past 400 Myrs. Regions above the Pacific and African large low shear velocity provinces are shown using blue and orange lines. Dashed, light-colored meridians indicate the separation of the Pacificand African hemispheres.

The seafloor is far thinner than the bulky landmass, and temperature from within Earth is “quenched” by the enormous volume of cold water that’s above it. Think of the gigantic Pacific Ocean compared with the opposite-side landmasses of Africa, Europe, and Asia—it makes sense that heat dissipates more quickly from the biggest seafloor in the world.

Previous research on this seafloor effect only went back 230 million years, meaning the new model, which goes back 400 million years, almost doubles the timeframe being studied.

There’s a surprising contradiction in the findings. The Pacific hemisphere has cooled about 50 Kelvin more than the African hemisphere, but the “consistently higher plate velocities of the Pacific hemisphere during the past 400 [million years]” suggest the Pacific was much hotter at a certain moment in time.

Was it covered by landmass at some point in the far distant past, keeping more heat inside? There are other possible explanations, but either way, the Pacific’s high tectonic activity today points to a heat disparity. The meltier the mantle, the more the plates can slide and slam together.

Student Astronomer Uses Ingenious Method to Find Galactic Missing Matter.

 

Distant galaxies used as ‘locator pins’ to detect ‘invisible’ gas cloud.

Half of the universe’s matter is ‘missing,’ but PhD student Yuanming Wang has developed an ingenious method to help track it down.

Astronomers have for the first time used distant galaxies as ‘scintillating pins’ to locate and identify a piece of the Milky Way’s missing matter.

For decades, scientists have been puzzled as to why they couldn’t account for all the matter in the universe as predicted by theory. While most of the universe’s mass is thought to be mysterious dark matter and dark energy, 5 percent is ‘normal matter’ that makes up stars, planets, asteroids, peanut butter, and butterflies. This is known as baryonic matter.

However, direct measurement has only accounted for about half the expected baryonic matter.

Yuanming Wang, a doctoral candidate in the School of Physics at the University of Sydney, has developed an ingenious method to help track down the missing matter. She has applied her technique to pinpoint a hitherto undetected stream of cold gas in the Milky Way about 10 light years from Earth. The cloud is about a trillion kilometers long and 10 billion kilometers wide but only weighing about the mass of our Moon.

The results, published in the Monthly Notices of the Royal Astronomical Society, offer a promising way for scientists to track down the Milky Way’s missing matter.

“We suspect that much of the ‘missing’ baryonic matter is in the form of cold gas clouds either in galaxies or between galaxies,” said Ms Wang, who is pursuing her PhD at the Sydney Institute for Astronomy.

“This gas is undetectable using conventional methods, as it emits no visible light of its own and is just too cold for detection via radio astronomy,” she said.

What the astronomers did is look for radio sources in the distant background to see how they ‘shimmered’.

“We found five twinkling radio sources on a giant line in the sky. Our analysis shows their light must have passed through the same cold clump of gas,” Ms Wang said.

Just as visible light is distorted as it passes through our atmosphere to give stars their twinkle, when radio waves pass through matter, it also affects their brightness. It was this ‘scintillation’ that Ms. Wang and her colleagues detected.

Dr. Artem Tuntsov, a co-author from Manly Astrophysics, said: “We aren’t quite sure what the strange cloud is, but one possibility is that it could be a hydrogen ‘snow cloud’ disrupted by a nearby star to form a long, thin clump of gas.”

Hydrogen freezes at about minus 260 degrees and theorists have proposed that some of the universe’s missing baryonic matter could be locked up in these hydrogen ‘snow clouds’. They are almost impossible to detect directly.

“However, we have now developed a method to identify such clumps of ‘invisible’ cold gas using background galaxies as pins,” Ms. Wang said.

Ms. Wang’s supervisor, Professor Tara Murphy, said: “This is a brilliant result for a young astronomer. We hope the methods trailblazed by Yuanming will allow us to detect more missing matter.”

The data to find the gas cloud was taken using the CSIRO’s Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope in Western Australia.

Dr. Keith Bannister, Principal Research Engineer at CSIRO, said: “It is ASKAP’s wide field of view, seeing tens of thousands of galaxies in a single observation that allowed us to measure the shape of the gas cloud.”

Professor Murphy said: “This is the first time that multiple ‘scintillators’ have been detected behind the same cloud of cold gas. In the next few years, we should be able to use similar methods with ASKAP to detect a large number of such gas structures in our galaxy.”

Ms. Wang’s discovery adds to a growing suite of tools for astronomers in their hunt for the universe’s missing baryonic matter.  By the late Jean-Pierre Macquart from Curtin University who used CSIRO’s ASKAP telescope to estimate a portion of matter in the intergalactic medium using fast radio bursts as ‘cosmic weigh stations.’

Earth has been habitable for billions of years – what are the chances?

 

We know the Earth has the potential to change climate rapidly, so we definitely know it can change over geological timescales. What are the chances it has remained able to support life.

It took evolution 3 or 4 billion years to produce Homo sapiens. If the climate had completely failed just once in that time then evolution would have come to a crashing halt and we would not be here now. So to understand how we came to exist on planet Earth, we’ll need to know how Earth managed to stay fit for life for billions of years.

This is not a trivial problem. Current global warming shows us that the climate can change considerably over the course of even a few centuries. Over geological timescales, it is even easier to change climate. Calculations show that there is the potential for Earth’s climate to deteriorate to temperatures below freezing or above boiling in just a few million years.

We also know that the Sun has become 30 per cent more luminous since life first evolved. In theory, this should have caused the oceans to boil away by now, given that they were not generally frozen on the early Earth – this is known as the “faint young Sun paradox”. Yet, somehow, this habitability puzzle was solved.

Scientists have come up with two main theories. The first is that the Earth could possess something like a thermostat – a feedback mechanism (or mechanisms) that prevents the climate ever wandering to fatal temperatures.

The second is that, out of a large number of planets, perhaps some just make it through by luck, and Earth is one of those. This second scenario is made more plausible by the discoveries in recent decades of many planets outside our solar system – so-called exoplanets. Astronomical observations of distant stars tell us that many have planets orbiting them, and that some are of a size and density and orbital distance such that temperatures suitable for life are theoretically possible. It has been estimated that there are at least 2 billion such candidate planets in our galaxy alone.

Scientists would love to travel to these exoplanets to investigate whether any of them have matched Earth’s billion years of climate stability. But even the nearest exoplanets, those orbiting the star Proxima Centauri, are more than four light-years away. Observational or experimental evidence is hard to come by.

Instead, I explored the same question through modelling. Using a computer program designed to simulate climate evolution on planets in general (not just Earth), I first generated 100,000 planets, each with a randomly different set of climate feedbacks. Climate feedbacks are processes that can amplify or diminish climate change – think for instance of sea ice melting in the Arctic, which replaces sunlight-reflecting ice with sunlight-absorbing open sea, which in turn causes more warming and more melting.

In order to investigate how likely each of these diverse planets was to stay habitable over enormous (geological) timescales, I simulated each 100 times. Each time the planet started from a different initial temperature and was exposed to a randomly different set of climate events. These events represent climate-altering factors such as supervolcano eruptions (like Mount Pinatubo but much much larger) and asteroid impacts (like the one that killed the dinosaurs). On each of the 100 runs, the planet’s temperature was tracked until it became too hot or too cold or else had survived for 3 billion years, at which point it was deemed to have been a possible crucible for intelligent life.

The simulation results give a definite answer to this habitability problem, at least in terms of the importance of feedbacks and luck. It was very rare (in fact, just one time out of 100,000) for a planet to have such strong stabilising feedbacks that it stayed habitable all 100 times, irrespective of the random climate events. In fact, most planets that stayed habitable at least once, did so fewer than 10 times out of 100. On nearly every occasion in the simulation when a planet remained habitable for 3 billion years, it was partly down to luck. At the same time, luck by itself was shown to be insufficient. Planets that were specially designed to have no feedbacks at all, never stayed habitable; random walks, buffeted around by climate events, never lasted the course.

This overall result, that outcomes depend partly on feedbacks and partly on luck, is robust. All sorts of changes to the modelling did not affect it. By implication, Earth must therefore possess some climate-stabilising feedbacks, but at the same time good fortune must also have been involved in it staying habitable. If, for instance, an asteroid or solar flare had been slightly larger than it was, or had occurred at a slightly different (more critical) time, we would probably not be here on Earth today. It gives a different perspective on why we are able to look back on Earth’s remarkable, enormously extended, history of life evolving and diversifying and becoming ever more complex to the point that it gave rise to us.

Scientists spot 6 alien worlds orbiting a star in strange harmony.

 

The planets around a star called TOI-178 know how to keep a beat  so smoothly, in fact, that scientists were able to discover new alien worlds by deciphering the system's music.

Astronomers poring through data from NASA's Transiting Exoplanet Survey Satellite (TESS) discovered three planets around a star dubbed TOI-178 (TOI stands for TESS Object of Interest). And when scientists looked at these observations more closely, they realized that the worlds seemed to be keeping time against each other. So they recruited some more instruments — and discovered the system hosts at least six planets, five of which tick off orbits in rhythm with the others. And unlike those of other synchronized systems, the planets are an unusually mixed bag.

"It is the first time we observe something like this," Kate Isaak, project scientist for the European Space Agency's Characterizing Exoplanet Satellite (CHEOPS), one of those additional instruments, said in a statement released by the University of Bern in Switzerland. "In the few systems we know with such a harmony, the density of planets steadily decreases as we move away from the star. In the TOI-178 system, a dense, terrestrial planet like Earth appears to be right next to a very fluffy planet with half the density of Neptune, followed by one very similar to Neptune."

Inspired by the mysterious TESS data showing three planets in an odd rhythm, the scientists behind the new research recruited additional instruments culminating in a dozen days of observing time with the CHEOPS telescope.

From those observations, the TOI-178 system appeared to include five planets, which orbited the star every 2, 3, 6, 10 and 20 days. But to the scientists, there appeared to be a gap in that sequence: They thought there should be another planet in the system, this one orbiting every 15 days.

Back to CHEOPS the researchers went, although they nearly missed their chance at studying the system in detail. Just as CHEOPS was due to take crucial observations of TOI-178, the satellite had to hustle away from a potential collision with a piece of space junk.

Despite the close call, all went smoothly in the end.

"To our great relief, this maneuver was done very efficiently and the satellite could resume observations just in time to capture the mysterious planet passing by," Nathan Hara, an astrophysicist at the University of Geneva and co-author on the new research, said in the statement. "A few days later, the data clearly indicated the presence of the additional planet and thus confirmed that there were indeed six planets in the TOI-178 system."

The innermost of those, it turns out, marches to a different beat, but the outer five orbit in harmony with each other. For every complete orbit of the outermost world, the next in completes three-quarters of an orbit, the middle world in the sequence makes two loops, then a planet that makes three orbits, and then a planet that makes six orbits; along the way, the planets occasionally line up, which caused the strange rhythm in the original TESS data.

Not only could the researchers spot the additional planets and sort out the complicated chain of orbits, but the scientists could also study the planets themselves, finding that these worlds range from 1.1 to 3 times the size of Earth, but with a range of densities, making them a curious mix of rocky super-Earths and gassy mini-Neptunes.

The scientists suspect that there may be more planets following the same chain of orbital alignments, although spotting these worlds would require longer periods of observation. Fortunately, because the star itself is so bright, the system is relatively easy to study; in particular, the researchers look forward to the data that NASA's James Webb Space Telescope and the European Extremely Large Telescope might be able to gather about the system once each begin work.

Neptune’s bumpy could reveal our solar system’s missing planets.

 

The modern solar system spins serenely, the planets locked in seemingly eternal circles around the sun. But it wasn’t always so. This tranquility appears to have emerged only after a gladiatorial period of planetary clashes—one in which titans ricocheted off each other, perhaps ejecting at least one rival sibling from the cosmic arena altogether.

Researchers have spent years scouring the solar system for clues of how that comparatively chaotic epoch might have played out. In a modest cluster of far-off rocks, David Nesvorny, a planetary scientist at the Southwest Research Institute, has found a figurative blood spatter suggestive of one particular conflict: a tussle between Neptune and an unknown planet that saw Neptune emerge victorious. His analysis, which appeared in late December in a not-yet-peer reviewed publication, adds further support to the notion that the solar system was once home to more than its current cadre of worlds.

To get this cohort of distant objects to pop out when you run the simulations, says Nathan Kaib, a planetary scientist at the University of Oklahoma who was not involved in the research, it seems like “you really need a planet to scatter [Neptune] off of.” That means, in theory, at least one extra planet may have been whizzing around the sun in eons past, knocking Neptune for a loop.

One way researchers can learn about events that took place more than four and a half billion years ago is by studying a current collection of ice balls known as the Kuiper Belt. Starting near Neptune’s orbit and extending outward from there, these frozen objects have been doing their own thing for eons, blind to most planetary drama.

The exception is the nearby Neptune, whose orbit has synched up with the orbits of many Kuiper Belt Objects (KBOs), including Pluto. This synchronization arises through subtle gravitational nudges from Neptune, which would have stopped those KBOs from forming in the first place. But since Pluto and its companions exist, researchers realized in the 80s and 90s, Neptune must have started out perhaps 10 to 20 percent closer to the sun and then slid outward later on (after Pluto and friends had already formed in peace).

But how did it relocate? One early idea was that it spiraled out smoothly as a result of regularly bumping into small objects, but a number of observations hinted at a more dramatic rearrangement: sometime in the solar system’s first millions of years, a number of near hits may have slingshotted planets into new positions on elliptical paths. Planetary scientists refer to this calamitous period euphemistically as an “instability.”

To get a better idea of what happened to Neptune during the instability, Nesvorny focused on one particular group of dozens of KBOs discovered over the last decade or so. Their orbits pass through the outskirts of the Kuiper Belt, but what really makes them special is how their paths tip roughly ten degrees out of the solar system’s flat disk—an indication that something pushed them out. “If you have certain orbit, it’s hard to tilt it differently,” Nesvorny says.

That something, according to new simulations from Nesvorny, is most likely a Neptune that slipped outward on an orbit with a just-so shape—one that falls somewhere between a perfect circle and a more severely squashed ellipse. Other scenarios just didn’t arrange this group of KBOs in the right place with the right slant.

To get Neptune moving in precisely that way would have taken a serious jolt, likely a close encounter with another planet of perhaps comparable mass. Previous studies, including work by Nesvorny, have suggested that the early solar system originally accommodated more giant planets than just Jupiter, Saturn, Uranus, and Neptune, a scenario that grows more likely if all the orbits went screwy for a while. “If you have an instability, you’re significantly more likely to lose planets than retain your original four,” Kaib says.

When Nesvorny runs hypothetical versions of the solar system in a simulation with a third ice giant (in addition to Uranus and Neptune), everything fits. If the mystery giant nearly collides with Neptune and Neptune’s orbit stretches as it moves out, giving the band of KBOs their distinctive 10 percent incline. The evidence is circumstantial, but suggestive.

“This is science,” he says. “You never know things for sure, but it’s compelling enough for me.”

Since Neptune survived the encounter, the additional ice giant was likely ejected from the solar system to wander the darkness of the Milky Way. However, if it didn’t receive quite enough of a kick to fly completely free of the sun’s gravity, it just might have come to rest perhaps 30 times farther from the sun than Neptune is today—exactly where some astronomers have predicted an unseen Planet Nine. The booted planet hangs around only around five percent of the time in simulations, Kaib says, but those are hardly unbeatable odds.

Better understanding the possible clashes between young planets, according to Nesvorny, is simply a matter of mapping the undisturbed outer reaches of the solar system in greater detail. This task will be a major goal for the upcoming Vera C. Rubin Observatory, which is expected to begin scientific operations in 2023.

“Because we have the Kuiper Belt,” he says, “it shouldn’t be that difficult to figure out what happened.

Astronauts were allowed to eat veggies grown in space.

 

If humans ever hope to colonize other planets or travel outside of our own solar system, we’re going to have to need a steady supply of food available for the brave travelers to consume. One way of ensuring that food is plentiful during such a mission would be to grow and harvest crops at the destination planet or, even better, onboard the spacecraft that is making the trip.

To that end, NASA has been slowly working to master the art of growing things in space. Most recently, astronauts aboard the International Space Station were tasked with growing radishes in the APH, or Advanced Planet Habitat. The process was delicate, with lots of preparation, but ultimately it all paid off in the form of healthy, perfectly edible radishes. And what do we do with edible radishes? We eat them.

After harvesting the radishes in early December, the radishes were compared with a control group of radishes that were grown under identical conditions back on Earth. The aim was to see if there was any real difference between growing the veggies on Earth as opposed to in the microgravity environment of space. If that was the only variable that was different, any changes in the end product could likely be attributed to the differences between the Earth environment and the lack of gravity on the ISS.

The good news is that the radishes were just as healthy as those grown on Earth. After being harvest, some were saved for a trip back to Earth where they will be studied and compared more closely with the control group, but that left several radishes that could be eaten by the crew.

Typically, astronauts eat prepared meals and food items that are sealed up in plastic and stored for months at a time. They heat up their food in a special “space oven” of sorts, and sometimes require rehydrating. So, things like fresh vegetables aren’t exactly on the menu when you’re an astronaut in space, and eating the radishes was quite a treat for the crew.

The team reported that it was “a most enjoyable experience” and that the radishes were just as good as anything grown fresh and harvested back on Earth. Another crop of radishes will be grown now that the first batch has been harvested, giving the scientists back on Earth and in space a larger sample size to study and spot any differences between Earth veggies and space veggies.

NASA space telescope will study Big Bang, origin of the universe.

 

NASA wants to peer back in time to the beginning of the universe. And with a new space telescope, scientists at the agency should be able to do just that.

The new telescope, scheduled for launch in either 2024 or 2025, "will map the entire sky to study the rapid expansion of the universe after the Big Bang, the composition of young planetary systems, and the history of galaxies," according to a statement from NASA.

It will provide a quantum leap from what we can see now, experts said. It's "like going from black-and-white images to color; it's like going from Kansas to Oz," said Allen Farrington, the telescope's project manager at NASA's Jet Propulsion Laboratory.

The telescope will survey the sky in optical light along with near-infrared light which, though not visible to the human eye, serves as a powerful tool for answering cosmic questions, NASA said. Astronomers will use the mission to gather data on more than 300 million galaxies, as well as more than 100 million stars in our own Milky Way.

The telescope, which will orbit the Earth once it's launched, is known as SPHEREx, an acronym for this mouthful: The Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer.

SPHEREx should be about the size of a subcompact car and, according NASA, will "map the entire sky four times, creating a massive database of stars, galaxies, nebulas (clouds of gas and dust in space) and many other celestial objects."

The $242 million telescope, which is scheduled to have a lifespan of about two years, will first look for evidence of something that may have happened less than a billionth of a billionth of a second after the Big Bang, which was 13 billion years ago. In that split second, "space itself may have rapidly expanded in a process scientists call inflation," NASA said.

Such ballooning would have influenced the distribution of matter in the cosmos, and evidence of that influence would still be around today, according to NASA. With SPHEREx, scientists will map the position of billions of galaxies across the universe relative to one another, looking for statistical patterns caused by inflation, NASA reported.

The patterns could help scientists understand the physics that drove that expansion.

Another goal of the telescope is to study the history of galaxy formation, starting with the first stars to ignite after the Big Bang and extending to present-day galaxies. 

Finally, scientists will use SPHEREx to look for water ice and frozen organic molecules – the building blocks of life on Earth – around newly forming stars in our galaxy.

"This amazing mission will be a treasure trove of unique data for astronomers,” Thomas Zurbuchen, associate administrator for NASA’s science mission directorate, said in a statement in 2019. 

“It will deliver an unprecedented galactic map containing ‘fingerprints’ from the first moments in the universe’s history," he said. "And we’ll have new clues to one of the greatest mysteries in science: What made the universe expand so quickly less than a nanosecond after the Big Bang?”

The SPHEREx team is slated to spend the next 29 months building the mission components before entering the next mission phase, when those components will be brought together, tested and launched.

Astronauts ring in new year from space with zero gravity 2021 ball drop.

 

The people of Earth rang in the year 2021 with fireworks and social distancing amid the global coronavirus pandemic last night. Even astronauts in space found a way to celebrate in their own unique way: a ball drop in zero gravity. 

In a video from the International Space Station on New Year's Eve (Dec. 31), five of the six astronauts living aboard the orbiting lab revealed what ringing in 2021 would look in in space. All they needed was a globe of the Earth.

"We wanted to take a moment to wish all of you a very happy New Year," NASA astronaut Kate Rubins said in the video, which NASA released on YouTube.

"One of the most famous New Year's Eve traditions is watching the ball drop in Times Square in New York City," NASA astronaut Victor Glover added, referring to the iconic celebration in which thousands of revelers pack New York City's Times Square to watch a glittering ball drop at midnight to mark the new year. 

This year, as New York City works to limit the spread of the ongoing coronavirus pandemic, officials blocked off Times Square to most revelers. 

"As many of us celebrate the new year from home, we brought this famous tradition to space to share with you," NASA astronaut Mike Hopkins said in the video. 

"Since we are in zero gravity, we have a special twist," added astronaut Soichi Noguchi of the Japan Aerospace Exploration Agency. 

That twist? In zero gravity, the ball can drop up.

"3, 2, 1, happy New Year!" the astronauts cheered in the video, which they did prerecord ahead of the actual new year. 

"We hope this inspires you to celebrate in your own way," NASA astronaut Shannon Walker added just ahead of that final count. 

Glover, Hopkins, Noguchi, Rubins and Walker are part of the International Space Station's seven-person Expedition 64 crew, with Russian cosmonauts Sergey Kud-Sverchkov and Sergey Ryzhikov of Roscosmos rounding out the team. Rubins, Kud-Sverchkov and Ryzhikov launched to the station in October on a Russian Soyuz rocket, while the rest of the crew launched to the station in November. They named the ship Resilience in part to honor humanity's battle against the coronavirus. 

Celebrating a New Year holiday in space is a bit trickier than it seems, but it is a vacation day for the station's crew. 

"The seven Expedition 64 crew members aboard the International Space Station will see the New Year 16 times today and take the day off on the first day of 2021," NASA officials said in a statement. 

The space station orbits the Earth once every 90 minutes or so, making 16 laps around the planet each day, hence the potential for 16 New Year celebrations. 

"The station orbits the Earth at 17,500 miles per hour (28,000 kilometers per hour) giving the crew the opportunity to see 16 sunrises and sunsets each day," NASA officials said. "The space residents set their clocks to GMT, or Greenwich Mean Time, and will start their new year at 12:00 a.m. GMT on Jan. 1, or five hours ahead of Eastern Standard Time.

Japan to build wooden satellites to cut space junk.

 

A major Japanese company and Kyoto University have joined forces to build what they hope will be the world's first satellites made out of wood.

Sumitomo Forestry said it has started research on tree growth and the use of wood materials in space.

The partnership will begin experimenting with different types of wood in extreme environments on Earth.

Space junk is becoming an increasing problem as more satellites are launched into the atmosphere.

Wooden satellites would burn up completely without releasing harmful substances into the atmosphere or raining debris on the ground when they plunge back to Earth. 

"We are very concerned with the fact that all the satellites which re-enter the Earth's atmosphere burn and create tiny alumina particles which will float in the upper atmosphere for many years," Takao Doi, a professor at Kyoto University and Japanese astronaut, Said.

"Eventually it will affect the environment of the Earth."

"The next stage will be developing the engineering model of the satellite, then we will manufacture the flight model," Professor Doi added.

As an astronaut he visited the International Space Station in March 2008.

During this mission, he became the first person to throw a boomerang in space that had been specifically designed for use in microgravity.

Sumitomo Forestry, part of the Sumitomo Group, which was founded more than 400 years ago, said it would work on developing wooden materials highly resistant to temperature changes and sunlight.

The wood it is using is an "R&D secret.

Space junk

Experts have warned of the increasing threat of space junk falling to Earth, as more spacecraft and satellites are launched.

Satellites are increasingly being used for communication, navigation and weather forecasting. Space experts and researchers have been investigating different options to remove and reduce the space junk.

Space junk travels at an incredibly fast speed of more than 22,300 mph, so can have cause considerable damage to any objects it hits.

In 2006 a tiny piece of space junk collided with the International Space Station, taking a chip out of the heavily reinforced window.

China says it's open to sharing moon rocks as Chang'e 5 samples head to the lab.

 

China has recovered the lunar samples collected by the daring Chang'e 5 mission and now work is underway to get the materials to the laboratory for science — and for sharing.

The Chang'e 5 reentry capsule landed in Inner Mongolia on Dec. 16, marking the end of the 23-day mission. The capsule, still containing the collected samples, was then airlifted to Beijing. 

The precious lunar materials were handed over for processing, analysis and storage at a specially designed facility belonging to the Chinese Academy of Sciences on Saturday, Dec. 19. The samples collected were found to weigh 3.81 lbs (1.731 kilograms) in total.

China's Chang'e 5 moon lander collected the material via a drill and a robotic arm, in the hard vacuum of the lunar surface. 

The plan was to drill a 6.6 ft (2 meters) deep hole to collect 1.1 lb (500 grams) of material, with the scoop grabbing 3.3 lbs (1.5 kg). “However while the lander started drilling there, the radar echograms showed that there were several layers of slates underneath the landing site. So we were unable to go further down when we reached about one meter deep, and we could face greater risk and overrun the time if we did not stop immediately,” Hu Hao, chief designer of the third phase of China's lunar exploration program, told CCTV.

This is expected to be the reason for the samples collected being less than the planned 4.4 lbs (2 kilograms).

Next, scientists have devised a special process to prevent the samples from being contaminated by particles on Earth. 

"We will unpack the samples in a vacuum environment, and transfer them to a nitrogen environment for storage and processing," Zhang Guangliang, chief designer of the ground application system of the Chinese Lunar Exploration Project, told Chinese media.

As the samples can easily be contaminated, CAS has designed a clean room which will minimize the pollution from Earth particles, said Zhang. He added that the utmost care would be taken to get the most of the invaluable material.

"We will use the equipment with highest accuracy and take the smallest portion of the lunar samples in research to realize the maximum research efficacy of the sample," he added.

Li Chunlai, deputy chief designer of the Chang'e-5 mission, said in a press conference on Dec. 17, a day after the landing, that the rocks were collected from a site in Oceanus Procellarum thought to be of great scientific value in areas including space weathering, volcanism, the regional geological background and evolution of the moon.

"We will conduct long-term and systematic research on lunar samples in the laboratory, including its structure, physical properties, chemical composition, isotopic composition, characteristics of the minerals and the geological evolution behind the samples. We hope to deepen our understanding of the origin and evolution of the moon," Li said.

Wu Yanhua, deputy director of the China National Space Administration, said in the same press conference that there would be three main uses of the samples: science, public outreach and sharing samples with other countries and scientists around the world. 

Part of the samples may also be used as diplomatic gifts according to precedents set by the United States and Russia, Wu added.

However, the elephant in the room was the matter of cooperation between China and the United States. Asked if the samples would be shared with NASA, Wu replied that the "Chinese government is ready to share the lunar samples including relevant data with all like-minded institutions from other countries," but the matter of cooperating with NASA depends on U.S. policy.

"It has been unfortunate however after a Congressional act adopted in 2011 U.S. space institutions have been blocked from cooperating with China, which is the Wolf Act. On the basis of equality, mutual benefit and win-win cooperation we are willing to conduct sincere and friendly cooperation with U.S. institutions," Wu stated. 

Wu also said that, in accordance with the Outer Space Treaty, outer space resources are the common asset of humanity. "We will act upon the relevant treaties," Wu said. 

Notably NASA has said it will buy lunar samples collected by commercial space companies. The move is part of the Artemis program which aims to send astronauts back to the moon in 2024.

The First Complete Observation of a 'Nanoflare' From Our Sun.

 

When Shah Bahauddin was deciding what to research for his PhD, he had no intention of becoming embroiled in one of the most vexing problems in astrophysics: why is the Sun's distant atmosphere so much hotter than it's roiling surface? 

His modest topic of choice was a tiny and brief loop of solar light, barely detectable considering the grand scheme of the Sun.

But size isn't everything. As it turns out, astronomers had been looking for a tiny eruption just like this one for more than half a century.

Flickering just below the Sun's super-hot corona, the explosion Bahauddin stumbled upon may very well be the first complete glimpse of a solar 'nanoflare' - from its sudden bright beginning to its inevitable sizzling demise. And we could just as easily have missed it.

If subtle and fleeting loops like this are a frequent affair, it could help explain how the Sun's corona came to be hundreds of times hotter than its visible surface - a mystery known as the coronal heating problem. 

"I thought maybe the loops made the surrounding atmosphere a bit hotter," admits Bahauddin. 

"I never thought that it would make so much energy that it might actually propel hot plasma to the corona and heat it up.

A billion times smaller than regular solar flares, nanoflares are incredibly difficult to spot and have only ever existed in theory, so the researchers are still reluctant to call the discovery by that official name. 

In theory, we have an idea of what a nanoflare should look like, but that's based on several assumptions. 

"Nobody actually knows because nobody has seen it before," Bahauddin says. "It's an educated guess, let's say."

Ever since astrophysicist Eugene Parker first proposed the idea of nanoflares in the 1970s, experts have been trying to figure out what these eruptions might look like in reality.

If they really do exist, they are nearly impossible to see, occurring millions of times a second without our instruments ever noticing. Although our technology is getting better.

In 2017, for instance, our best glimpse of a nanoflare came from the absence of a bigger one. An active region in the Sun, which hosted very few normal-sized flares, showed a curious level of heating. Something unseen clearly had to be contributing energy to the atmosphere. A nanoflare suited the case.

Technically, to be deemed a proper nanoflare, a blast of heat must be triggered by the Sun's tangled magnetic fields, which are produced by bubbles of churning plasma below.

When these fields reconnect, they are thought to cause an explosive process - equivalent to around 10 billion tonnes of TNT. This energises and accelerates surrounding particles, and if all that activity is strong enough to heat the Sun's corona, thousands of kilometres above, it's called a nanoflare.

Above: A close-up of one of the loop brightenings studied. Each inset frame zooms in further (from left to right), showing the putative nanoflare.

Analysing some of the finest images of the Sun's corona, taken from NASA's Interface Region Imaging Spectrograph, or IRIS satellite, the new discovery ticks both those boxes.

Not only was this tiny loop of light millions of degrees hotter than its surroundings, the way it erupted appeared curious. 

"You have to examine if the energy from a nanoflare can be dissipated in the corona," explains Bahauddin. 

"If the energy goes somewhere else, that doesn't solve the coronal heating problem." 

Looking at the data, it appeared that heavy elements, like silicon, became much hotter and more energetic than lighter elements like oxygen, which is exactly the opposite of what you'd expect.

Searching for a type of heat that could impact an oxygen atom differently to a silicon atom in just that way, researchers found only one match: a magnetic reconnection event.

Under these complex chaotic circumstances, heavier ions have an advantage, because they can plow through the crowds of lighter ions and steal all the energy, accruing great heat in the process.

But that was only a hypothesis, and it seemed like a long shot. The conditions needed to achieve this type of heating required just the right proportion of silicon to oxygen. Could that really exist?

"So we looked back at the measurements, and saw that the numbers exactly matched," explains Bahauddin.

To the team's astonishment, it appeared they had stumbled upon a real explanation for coronal heating. The next step was to see if it actually heated the corona. 

Analysing data from the region right above the bright loop, just before it flared, the team discovered their final clue.

"And there it was, just a 20-second delay," recalls Bahauddin. "We saw the brightening, and then we suddenly saw the corona got super-heated to multi-million degree temperatures."

Already, the team has found nine other loops on the surface of the Sun that also show a similar transfer of energy to the corona.

Whether this localised heating is enough to explain the higher temperatures found across the Sun's corona will depend on how many other loops astronomers can find. 

If their frequency and locations are often and widespread enough, these bursts of energy could at least partially answer the mystery surrounding coronal heating.

Yet in all likelihood, astronomers think there are probably multiple invisible mechanisms at play. It's probably not just one thing that is heating the Sun's atmosphere to such blistering temperatures, and many of the ideas we have now are not mutually exclusive.

Other theories include electromagnetic waves washing outwards from the Sun, heating particles and allowing them to 'surf' to the outer atmosphere.

Are there secret oceans hiding on the moons of Uranus?

 

The moons of Uranus could be sloshing with oceans hiding just below the surface. 

Icy worlds speckle our solar system — from Jupiter's moon Europa to Saturn's moon Enceladus, scientists have been investigating these alien worlds, discovering subsurface oceans hidden under their icy crusts. Now, researchers have turned their gaze to the moons orbiting Uranus, searching for secret oceans.

In a new study, presented at the Dec. 15 AGU's Fall Meeting 2020, researchers led by Benjamin Weiss, a planetary scientist at the Massachusetts Institute of Technology, have developed a method for future missions to confirm the existence of subsurface oceans on worlds like the moons of Uranus. With this work, the team also hopes to further our understanding and knowledge of potentially habitable worlds. 

"The big question here is, Where are habitable environments in the solar system?" Weiss said in a statement. Discovering subsurface oceans on Europa and Enceladus makes "a lot of us wonder whether there are many moons out there that, although they're small, may still be warm."

Uranus has 27 moons total, but the planet has five especially large moons — Titania, Oberon, Umbriel, Ariel and Miranda. When Voyager 2 swooped by the Uranus system back in 1986, it captured images that showed that these five big moons are made up of equal parts rock and ice and are heavily cratered. These images also showed physical signs of liquid water erupting through a world and freezing on its surface, called cryovolcanism. 

The phenomenon could be caused by a subsurface ocean similar to what we see on Enceladus, which expels plumes from its ocean out into space. 

To determine whether a future spacecraft could definitively discover a subsurface ocean on one of these worlds, the researchers in this work calculated how strong the magnetic field Uranus would induce on a moon's ocean. 

As a moon orbits a planet, that planet's magnetic field tugs at the moon, keeping it in its orbit. This tug from the magnetic field generates an electrical current that can create its own magnetic field, called an induced magnetic field. This induced field is thought to be created by a layer of some kind of electrically conductive fluid, like a subsurface ocean. 

"If there’s liquid water there and it’s a little bit salty like ocean water on the Earth," Weiss said about Uranus' moons, "then it can be conducting, meaning currents can flow in it." 

An induced magnetic field on one of these moons would look very different from Uranus' magnetic field to an instrument on a nearby spacecraft, making them observable from nearby.  

In 1998, scientists used this same technique to confirm Europa's subsurface ocean and the ocean inside another of Jupiter's moons, Callisto. Europa's induced magnetic field was about 220 nanoteslas strong; Callisto's was about 40.

Instead of sending a spacecraft, Weiss and his team used theoretical models of Uranus' magnetic field to calculate the possible induced magnetic fields of the planet's five biggest moons. Miranda's induced magnetic field was determined to be the strongest, at 300 nanoteslas. While this does not confirm the presence of oceans on the worlds, Miranda, as well as Ariel, Umbriel and Titania, likely have induced magnetic fields strong enough to be detectable with existing spacecraft technology, according to Weiss in the statement. 

Now, while subsurface oceans might exist on these moons, it's likely that they would be much farther beneath the worlds' surfaces than those on worlds orbiting Jupiter because Uranus' moons are colder so they'd likely have a thicker icy crust, David Stevenson, a planetary scientist at the California Institute of Technology, said in the same statement. 

NASA doesn't have any current plans to send a probe to Uranus, however, the agency is considering a Neptune-bound mission called Trident that could gather information about Uranus as well, according to the statement; NASA will decide that mission's fate next year. However, a probe sent to look for these oceans would have to get really close to at least one of the planet's moons and such a mission likely won't happen until at least 2042, according to Stevenson.

Tonight, Jupiter And Saturn Will Appear Closer Than They've Been in 800 Years.

Star-gazers are in for a treat this week, as Jupiter and Saturn are about to get closer to each other in Earth's night sky than they have been for nearly 800 years. Set up your telescope, hope for a clear night, and get ready.

The celestial synchronisation has been in the works since summer as Jupiter and Saturn have been moving closer together in the night sky, and between 16-25 December they'll be separated by only 1/5th the diameter of a full moon.

While the planets won't physically be close to each other at all, of course, they'll look like a single point of bright light to anyone looking up at the night sky.

"Alignments between these two planets are rather rare, occurring once every 20 years or so, but this conjunction is exceptionally rare because of how close the planets will appear to one another," says astronomer Patrick Hartigan from Rice University.

"You'd have to go all the way back to just before dawn on March 4, 1226, to see a closer alignment between these objects visible in the night sky.

To get the best viewing experience for this spectacular show, you're going to need to be somewhere near the equator – but if the skies are clear then the alignment should still be visible from just about anywhere on Earth.

The pair of planets will show up in the night sky for about an hour after sunset each evening, according to astronomers. If you're hoping to catch a glimpse yourself, you'll need to point your telescope towards the western sky.

"On the evening of closest approach on Dec 21 they will look like a double planet, separated by only 1/5th the diameter of the full Moon," says Hartigan. "For most telescope viewers, each planet and several of their largest moons will be visible in the same field of view that evening.

"The further north a viewer is, the less time they'll have to catch a glimpse of the conjunction before the planets sink below the horizon.

The planets will be bright enough in the sky to be visible in twilight, which might be the best time to try and take a look at them if you're in the US. Websites should help you work out where you should be looking from your vantage point.

While this kind of alignment hasn't occurred since the Middle Ages, it will happen again fairly soon, in March 2080. After that though, Jupiter and Saturn won't get as close in our night sky until 2400.

When we're dealing with these sorts of timescales, it always pays to keep up to date with what's happening around the Solar System – you don't want to miss something incredible.

Huge methane cache beneath Arctic could be unlocked by the moon.

The moon could be affecting how much methane is released from the Arctic Ocean seafloor, a new study finds. 

The tides, which are controlled by the moon, affect how much methane is released from seafloor sediments: Low tides mean less pressure and more methane released, while high tides create more pressure, and therefore less methane emission.

The research was conducted in the west-Svalbard region of the Arctic, with the findings.

"It is the first time that this observation has been made in the Arctic Ocean. It means that slight pressure changes can release significant amounts of methane. This is a game-changer and the highest impact of the study," study coauthor, Jochen Knies, a marine geologist at the Centre for Arctic Gas Hydrate, Environment and Climate (CAGE), said in a statement. 

Methane is a greenhouse gas, which contributes to global warming by trapping and holding heat in the atmosphere.  Huge methane reserves lurk beneath the seafloor and ocean warming is expected to unlock some of that trapped methane. So understanding how the tides impact these seafloor methane emissions is important for future climate predictions.

To find this tidal effect, the team measured the pressure and temperature inside the sediments and found that gas levels near the seafloor rise and fall with the tides.

Scientists spot water ice reservoir on Mars.

 

When humans get to Mars one day, they'll have some pressing needs. One of those is water. Water is heavy and hard to transport through space, so ideally they'll be able to find what they need to survive on Mars itself. 

A new study led by researchers at the Planetary Science Institute (PSI) points to a "large, previously unrecognized reservoir of water ice" in the Nereidum Montes region of Mars.Viscous Flow Features (VFFs), icy formations found on the red planet. 

VFFs have been compared with glacial formations on Earth and could be a potential source of water for astronauts.

"Our radar analysis shows that at least one of these features is about 500 meters thick and nearly 100 percent ice, with a debris covering at most ten meters thick," said PSI senior scientist Daniel Berman, lead author of the paper, in a statement on Monday.

These water ice deposits could represent "potentially the largest concentrations of any non-polar region in the southern hemisphere," according to PSI. The researchers used data from NASA's Mars Reconnaissance Orbiter to locate the VFFs, which date to within the last few million years of the planet's history.

The study ties in with other research on the history and current presence of water on Mars. NASA shared a "treasure map" of water ice deposits on Mars in 2019.

While it's tempting to pack a hair dryer and a straw and head for Nereidum Montes, it won't be that simple for future red planet explorers. "This region would be an interesting landing site due to the large amounts of ice, which could be used as a source for water," Berman said. "Unfortunately, it is very mountainous terrain and it would likely be very difficult to land there.