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Researchers discover fossils of tiny mammals that frolicked among dinosaurs

The little tree-climber, Agilodocodon scansorius


Excerpt from 
sciencerecorder.com



Two new fossil discoveries push the timeline back on the appearance of burrowing and tree-climbing mammals. Fossils of the shrew-sized creatures found in China date to the age of the dinosaurs and show that mammals of that period were already highly specialized, well-performing animals. One of the rodent-like animals was likely a long-clawed tree-dweller, while the other was shovel-pawed tunnel-digger.

 
The little tree-climber, Agilodocodon scansorius, is the earliest arboreal mammal ever discovered. A report published this week in Science Magazine highlights its traits suited for its habitat, including long claws, spade-like front teeth for gnawing into bark, and flexible elbows and ankles. It is believed to have weighed up to 40 grams, a bit less than a typical hotdog without condiments, and lived about 165 million years ago in what is Mongolia today.

“When we got into the study of Agilodocodon, we realized that the outline for the horny sheath of the claws is preserved,” Zhe-Xi Luo, professor of organismal biology and anatomy at the University of Chicago, said in an interview. “Those soft tissues are not preserved in the vast majority of mammals. It has a very long, curved narrow claw — one feature to show that it is a good climber.” 


Image: Artist's rendition Docofossor brachydactylus
Docofossor brachydactylus


In a report published in the same issue of Science, the other mammal, called Docofossor brachydactylus, is described to have stood no more than 9 centimeters tall and weighed only 17 grams, about the size of a juvenile mouse. Docfossor is the earliest underground-dwelling mammal ever found and shares similarities with the African golden mole, having short, wide digits suitable for digging. The little digger is estimated to have lived some 160 million years ago in what is today Ganggou Fossil Site in China’s Hebei province.

Both fossils are of creatures that belong to the order Docodonta. The discoveries are the first to provide full skeletons of this order, which had previously been characterized by evidence from fossils of teeth, jaws, and bits of skull.

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Planck telescope puts new datestamp on first stars


Polarisation of the sky
Planck has mapped the delicate polarisation of the CMB across the entire sky



Excerpt from bbc.com

Scientists working on Europe's Planck satellite say the first stars lit up the Universe later than previously thought.

The team has made the most precise map of the "oldest light" in the cosmos.

Earlier observations of this radiation had suggested the first generation of stars were bursting into life by about 420 million years after the Big Bang.

Planck's data indicates this great ignition was well established by some 560 million years after it all began.

"This difference of 140 million years might not seem that significant in the context of the 13.8-billion-year history of the cosmos, but proportionately it's actually a very big change in our understanding of how certain key events progressed at the earliest epochs," said Prof George Efstathiou, one of the leaders of the Planck Science Collaboration.

Subtle signal

The assessment is based on studies of the "afterglow" of the Big Bang, the ancient light called the Cosmic Microwave Background (CMB), which still washes over the Earth today.
Prof George Efstathiou: "We don't need more complicated explanations"

The European Space Agency's (Esa) Planck satellite mapped this "fossil" between 2009 and 2013.

It contains a wealth of information about early conditions in the Universe, and can even be used to work out its age, shape and do an inventory of its contents.

Scientists can also probe it for very subtle "distortions" that tell them about any interactions the CMB has had on its way to us.

Forging elements

One of these would have been imprinted when the infant cosmos underwent a major environmental change known as re-ionisation.

Prof Richard McMahon: "The two sides of the bridge now join"
It is when the cooling neutral hydrogen gas that dominated the Universe in the aftermath of the Big Bang was then re-energised by the ignition of the first stars.

These hot giants would have burnt brilliant but brief lives, producing the very first heavy elements. But they would also have "fried" the neutral gas around them - ripping electrons off the hydrogen protons.

And it is the passage of the CMB through this maze of electrons and protons that would have resulted in it picking up a subtle polarisation.

ImpressionImpression: The first stars would have been unwieldy behemoths that burnt brief but brilliant lives


The Planck team has now analysed this polarisation in fine detail and determined it to have been generated at 560 million years after the Big Bang.

The American satellite WMAP, which operated in the 2000s, made the previous best estimate for the peak of re-ionisation at 420 million years. 

The problem with that number was that it sat at odds with Hubble Space Telescope observations of the early Universe.

Hubble could not find stars and galaxies in sufficient numbers to deliver the scale of environmental change at the time when WMAP suggested it was occurring.

Planck's new timing "effectively solves the conflict," commented Prof Richard McMahon from Cambridge University, UK.

"We had two groups of astronomers who were basically working on different sides of the problem. The Planck people came at it from the Big Bang side, while those of us who work on galaxies came at it from the 'now side'. 

"It's like a bridge being built over a river. The two sides do now join where previously we had a gap," he told BBC News.

That gap had prompted scientists to invoke complicated scenarios to initiate re-ionisation, including the possibility that there might have been an even earlier population of giant stars or energetic black holes. Such solutions are no longer needed.

No-one knows the exact timing of the very first individual stars. All Planck does is tell us when large numbers of these stars had gathered into galaxies of sufficient strength to alter the cosmic environment. 

By definition, this puts the ignition of the "founding stars" well before 560 million years after the Big Bang. Quite how far back in time, though, is uncertain. Perhaps, it was as early as 200 million years. It will be the job of the next generation of observatories like Hubble's successor, the James Webb Space Telescope, to try to find the answer.

JWSTBeing built now: The James Webb telescope will conduct a survey of the first galaxies and their stars
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The history of the Universe

Graphic of the history of time
  • Planck's CMB studies indicate the Big Bang was 13.8bn years ago
  • The CMB itself can be thought of as the 'afterglow' of the Big Bang
  • It spreads across the cosmos some 380,000 years after the Big Bang
  • This is when the conditions cool to make neutral hydrogen atoms
  • The period before the first stars is often called the 'Dark Ages'
  • When the first stars ignite, they 'fry' the neutral gas around them
  • These giants also forge the first heavy elements in big explosions
  • 'First Light', or 'Cosmic Renaissance', is a key epoch in history
line

The new Planck result is contained in a raft of new papers just posted on the Esa website. 

These papers accompany the latest data release from the satellite that can now be used by the wider scientific community, not just collaboration members.
Dr Andrew Jaffe: "The simplest models for inflation are ruled out"
Two years ago, the data dump largely concerned interpretations of the CMB based on its temperature profile. It is the CMB's polarisation features that take centre-stage this time.
It was hoped that Planck might find direct evidence in the CMB's polarisation for inflation - the super-rapid expansion of space thought to have occurred just fractions of a second after the Big Bang. This has not been possible. But all the Planck data - temperature and polarisation information - is consistent with that theory, and the precision measurements mean new, tighter constraints have been put on the likely scale of the inflation signal, which other experiments continue to chase.
What is clear from the Planck investigation is that the simplest models for how the super-rapid expansion might have worked are probably no longer tenable, suggesting some exotic physics will eventually be needed to explain it.
"We're now being pushed into a parameter space we didn't expect to be in," said collaboration scientist Dr Andrew Jaffe from Imperial College, UK. "That's OK. We like interesting physics; that's why we're physicists, so there's no problem with that. It's just we had this naïve expectation that the simplest answer would be right, and sometimes it just isn't."

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Archaeologists Uncovering Legendary Lost City of Poseidon

A view of the excavations at Helike. Drekis, Wikimedia CommonsExcerpt from popular-archaeology.com A team of scholars and students will return to explore and investigate the site now thought to be the remains of the lost city of Helike, the lege...

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The Mystery of the Blonde-haired Tarim Mummies of China



Excerpt from 
historicmysteries.com
By Shelly Barclay

The Tarim Mummies or the Mummies of Xinjiang are mysterious mummies that were discovered in the foothills of the Tian Shan Mountains in China. What is so mysterious about them is that some of them date back to roughly 4,000 years ago, a time when it was thought that there were no westerners in that area. However, there must have been, because the Tarim mummies are Caucasian. Not only that, but they wear similar garments and share similar burial practices of some European countries.



The first of the Tarim mummies was discovered by Wang Binghua in 1978. Wang had been searching for ancient settlements along in the northeast of Xinjiang when a local man directed him to Quizilchoqa. It was there that Wang uncovered the first mysterious Tarim mummy. Over time, these mummies were discovered in four different sites in the Tarim Basin area.  More than one hundred of them have been uncovered so far.


The Tarim mummies are unusually well preserved. This is interesting because the people who buried them did not practice mummification. The sites where these mummies have been found, lie on the edges of the Taklamakan Desert. When these ancient people buried their dead, the hot climate and rocky soil helped to keep the deceased’s body preserved, though it should have decomposed hundreds of years ago. Some of these corpses rival the Ancient Egyptian mummies in their extraordinary preserved state.
Another very strange thing about the Tarim mummies is the attire in which they were buried. If the fact that some of them had blond hair and blue eyes hadn’t given away the fact that they were westerners that had settled in what is now Xinjiang, the clothing they wore when they were buried would have. 


One of the mummies, the Yingpan Man, was six feet six inches tall and wore a red tunic with gold embroidery. He also wore a gold foil burial mask. This burial clothing is far more indicative of western influence than of Eastern. Other Tarim mummies have also been found wearing decidedly western clothing. One of the oddest bits of clothing found any of these mummies are the flat-brimmed pointy “witch hats” that were discovered on the “Witches of Subeshi.”

Researchers have been able to decipher a number of things about the people who buried these mummies since their discovery. This is largely due to the work of Dr. Victor Mair, the man who brought the Tarim mummies into the public eye. It is known that the ancient people rode horses, used chariots and had at least some medical knowledge. One of the Tarim mummies was found with evidence of a surgical wound on its neck, which had been sutured at some point.

Since the discovery of the caucasian-featured Tarim mummies in Xinjiang, scientists have been trying to uncover links between the ancient people who buried these mummies and modern citizens of the area. Thus far, several links have been discovered and hypothesized, but it is difficult to make them public or credible because of political unrest in the area. Nonetheless, there are many people who are certain that the Tarim mummies represent the first Caucasians to settle in the area. If this is fact, then it will mean that western man settled in the area roughly one thousand years before scientists had previously thought they did.

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New internet neutrality: FCC chairman proposes strong new rules

Excerpt from mercurynews.comThe federal government's top communications regulator on Wednesday called for strong new rules to bar Internet and wireless providers from blocking, slowing or discriminating against consumers' access to particular websi...

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Dinosaurs were NOT wiped out by a global firestorm: Asteroid impact was not hot enough to ignite nearby plants, study claims

Excerpt from dailymail.co.ukBy Jonathan O'Callaghan UK researchers studied the asteroid impact 66 million years agoThey found the heat near the impact site in Mexico was not intense enough to ignite plant materialA heat pulse lasted less than a minute...

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Taiwan Conference Report / Solar System Situation Update

Taiwan conference was a huge success. Because Taiwan is one of the main centers of the positive Dragon forces, it could grow a very strong Lightworker and Lightwarrior community. The conference took place very close to the location where Taiwanese Drag...

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The Weirdest, Coolest Stuff We’ve Learned About Rosetta’s Comet So Far


Various features on a smooth part of the comet's surface in the region named Imhotep.


Excerpt from wired.com

The Rosetta spacecraft has been studying comet 67P/Churyumov-Gerasimenko up close since August, collecting data of unprecedented detail and taking pictures of a starkly beautiful comet-scape. While the Philae lander has enjoyed much of the spotlight—partly thanks to its now-famous triple landing—Rosetta has been making plenty of its own discoveries.  

One of the biggest came last month, when scientists found that the chemical signature of the comet’s water is nothing like that on Earth, contradicting the theory that crashing comets supplied our planet with water. Comet 67P belongs to the Jupiter family of comets, and the findings also imply that these kinds of comets were formed at a wider range of distances from the sun than previously thought, says Michael A’Hearn, a planetary scientist at the University of Maryland, College Park, and member of the Rosetta science team.  

Today, scientists have published the first big set of results from Rosetta in a slew of papers in the journal Science. The results include measurements and analyses of the comet’s shape, structure, surface, and the surrounding dust and gas particles. Here are just a few of the amazing things they’ve discovered about Rosetta’s comet so far: 

The surface is fantastically weird  

The comet has quite the textured landscape, covered with steep cliffs, boulders, weird bumps, cracks, pits, and smooth terrain. There are fractures of all sizes, including one that’s several yards wide and stretches for more than half a mile along the comet’s neck. Researchers don’t yet know what caused these cracks.  The pits have steep sides and flat bottoms, ranging in size from a few tens to hundreds of feet wide. Jets of dust shoot out from some of the pits, suggesting that the ejection of material formed these features.  Another strange feature is what scientists are calling goosebumps—weird bumpy patches found particularly on steep slopes.

While other features such as pits and fractures range in sizes, all of the goosebumps are about 10 feet wide. No one knows what kind of process would make the bumps, but whatever it is could have played an important part in the comet’s formation. It may be breezy  Rosetta spotted dune- and ripple-like patterns,wind tails behind rocks, and even moats surrounding rocks, suggesting that a light breeze may blow dust along the surface. Such a gentle wind would have to come from gases leaking from below.

Because of the extremely low gravity on the comet, it wouldn’t take a strong gust to blow things around. It may have formed from two separate pieces  Or not. The most distinct feature of comet 67P is its odd, two-lobed shape, which resembles a duck. Although scientists have seen this lobed structure in other comets before, namely Borrelly and Hartley 2, none are as pronounced as comet 67P’s. Borrelly and Hartley 2 look more like elongated potatoes while 67P has a clearly defined head and body. The strange shape suggests the comet was once two separate pieces called cometesimals—what are now the duck’s head and body—that stuck together. 

The other possibility is that erosion ate away the parts around the neck. Preliminary evidence points to the first hypothesis.

“Probably most of us on the OSIRIS team lean toward thinking it was two cometesimals,” A’Hearn said. (OSIRIS is one of Rosetta’s imaging instruments.) But the scientists won’t have conclusive evidence until they study the comet in more detail. For example, they now see layering along the neck—if erosion carved out the comet’s duck shape, they should find the same same layering pattern continuing onto the other side of the neck. 

Black, with a tinge of red  

Even Rosetta’s color pictures show a grayish comet, but if you were to see it in person, you would see a pitch-black chunk of dust and ice, as it reflects only six percent of incoming light. By comparison, the moon reflects 12 percent of incoming light and Earth reflects 31 percent. But comet 67P’s not completely black, as it has a hint of red. Water, water, nowhere?  The comet’s covered in opaque, organic compounds. Although comet 67P is undoubtedly icy, it hardly shows any water ice on its surface at all. 

Which isn’t too surprising, as comets Tempel 1 and Hartley 2 didn’t have much ice on their surfaces either, A’Hearn says. Rosetta has yet to see sunlight reach every side of the comet yet, so there may still be some icy patches hidden from view.  But, researchers do see the comet spraying water vapor into space, which means water ice likely lies just beneath the surface. The ice doesn’t have to be more than a centimeter deep to be invisible from the infrared instruments that detect the ice. Indeed, the data from Philae’s first bounce suggested that there’s a hard layer of ice beneath 4 to 8 inches of dust. 

This duck floats  

If you could find a big enough pond, that is. Like other known comets, the density of comet 67P is about half that of water ice. Initial measurements reveal that it’s also very porous—as much as 80 percent of it may be empty space. Rosetta has found depressions, which may have formed when the surface collapsed over particularly porous material underneath. 

Different from every angle

As the comet nears the sun, it heats up, and ices and other volatile chemicals sublimate, spraying gases into space. So far, the most prominent gases that have been ejected are water vapor, carbon dioxide, and carbon monoxide. They spew out in different amounts from different parts of the comet. In particular, a lot of the water has been observed gushing out from the neck.

The comet will continue to get more active as it reaches its closest approach to the sun in mid-August. It will burst with stronger jets of gas and dust, and maybe even blast off chunks of itself. If the comet is this interesting now, A’Hearn says, just wait until it gets to its nearest point to the sun, when it’s just 1.29 times farther from the sun than Earth is.

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Gullies suggest comet Vesta once had flowing water on its surface



This image of the giant asteroid Vesta was taken by NASA's Dawn spacecraft, as part of a rotation characterization sequence on July 24, 2011


Excerpt from natmonitor.com

NASA’s Dawn spacecraft is currently approaching the dwarf planet Ceres, the largest object in the asteroid belt that lies between Mars and Jupiter. However, from 2011 to 2013 Dawn collected extensive data on Vesta, the second largest object in the asteroid belt and one of the largest known comets in our solar system.

The data collected from Vesta is still being analyzed and will continue to be for years to come. As the data is examined interesting new information about the giant asteroid is coming to light. Vesta which is very cold and has no atmosphere has long thought to be dry. A new study published in the journal Earth and Planetary Science Letters casts doubt on that assumption.
While there are certainly no rivers and lakes on Vesta, photographs taken by Dawn show evidence of short lived flows of water mobilized material on the surface.

“Nobody expected to find evidence of water on Vesta. The surface is very cold and there is no atmosphere, so any water on the surface evaporates. However, Vesta is proving to be a very interesting and complex planetary body,” said Jennifer Scully, postgraduate researcher at the University of California, Los Angeles in a statement.

The research could change some basic assumptions in planetary science.

“These results, and many others from the Dawn mission, show that Vesta is home to many processes that were previously thought to be exclusive to planets. We look forward to uncovering even more insights and mysteries when Dawn studies Ceres,” said UCLA’s Christopher Russell, principal investigator for the Dawn mission.
The curved gullies on vesta are very different from what would be expected from dry material flows, say the researchers.

“We’re not suggesting that there was a river-like flow of water. We’re suggesting a process similar to debris flows, where a small amount of water mobilizes the sandy and rocky particles into a flow. These features on Vesta share many characteristics with those formed by debris flows on Earth and Mars,“ said Scully.

The leading theory so far is that Vesta has small patches of ice beneath the surface, possibly deposited by impacts from other comets. Later impacts could have heated the ice enough to thaw some of the water, releasing it into the crater.

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Tool making arose earlier among human ancestors


Coming to grips with tool-making evolution
A modern human hand grasps a fossil metacarpus from a hominin ancestor who may have been able to craft tools. A new study suggests the adaptations enabling a precise and forceful grip developed 500,000 years earlier than previously theorized. (Tracy L. Kivell, Matthew M. Skinner)
Excerpt from latimes.com
By Geoffrey Mohan 


Our ape-like ancestors may have stopped dragging their knuckles and started making tools a half million years earlier than previously thought, according to a new study.
The study, published online Thursday in the journal Science, suggests that the art of tool making may not be exclusive to the genus Homo, which led to modern Homo sapiens. At least one species in the dead-end genus Australopithecus appears to have enough of the hand characteristics that would have made tool crafting possible, the study found.

That would mean that the credit for tool use would now be shared between Homo habilis -- most often thought to be the progenitor of tool-making hominins -- and Australopithecus africanus, a species that wandered around southern Africa about 2-3 million years ago.
Since then, modern Homo sapiens has used a lot of his tool-making ability to type out arguments over which ancestor first flaked a stone into a sharp-edged tool. So it’s unlikely that one study will settle the matter...

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Extraterrestrial Neighbors? Study Says Blast Of Unknown Radio Waves Came From Outside Our Galaxy

Excerpt from  npr.org On a graph, they look like detonations. Scientists call them "fast radio bursts," or FRBs, mysterious and strong pulses of radio waves that seemingly emanate far from the Milky Way. The bursts are rare; they normall...

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New data that fundamental physics constants underlie life-enabling universe

Excerpt from spacedaily.com For nearly half a century, theoretical physicists have made a series of discoveries that certain constants in fundamental physics seem extraordinarily fine-tuned to allow for the emergence of a life-enabling universe.Thi...

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The Best Bet for Alien Life May Be in Planetary Systems Very Different From Ours




Excerpt from wired.com


In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.

But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.

At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.

But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.

M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.

“By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.

That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.

This illustration shows Kepler-186f, the first rocky planet found in a star's habitable zone. Its star is an M dwarf.
This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf. NASA Ames/SETI Institute/JPL-Caltech


M dwarfs have another thing going for them. They’re the most common star in the galaxy, comprising an estimated 75 percent of the Milky Way’s hundreds of billions of stars. If Dressing’s estimates are right, then our galaxy could be teeming with 100 billion Earth-sized planets in their stars’ habitable zones.

To be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.
Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.

And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.

But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.

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