[James Webb was an incredible step forward. Jan]
Here’s the video: https://www.youtube.com/watch?v=0pNDlWX4R5o&t=341s
Author: jlamprecht
Space: NASA prepping for September arrival of OSIRIS-REx asteroid sample
[What will be even more amazing is when they return the many samples of soil and rock from Mars that the lander is busy gathering. That will take several years. But they'll have to launch it from the surface of Mars. That will be an amazing first. That will be difficult. Jan]
Practice makes perfect, and there are no do-overs once teams recover the sample from asteroid Bennu.
OSIRIS-REx’s asteroid sample is coming home.
OSIRIS-REx, NASA’s first asteroid sample return mission, took a bite out of the space rock Bennu in October 2020 and is on course to return that sample to Earth just over seven years to the day after it launched.
As the probe — whose name is short for "Origins Spectral Interpretation Resource Identification Security-Regolith Explorer" — flies its return trajectory through space, teams on Earth are preparing for the sample’s Sept. 24 landing in the Utah desert.
If all goes as planned, OSIRIS-REx’s sample return capsule will separate from the primary vehicle and enter Earth’s atmosphere at 10:41 a.m. EDT (1441 GMT) on Sept. 24. Built to withstand the heat and turbulence that comes with punching through the atmosphere, the capsule is expected to parachute down to a relatively soft landing at approximately 10:54 a.m. EDT (1454 GMT).
"Once the sample capsule touches down, our team will be racing against the clock to recover it and get it to the safety of a temporary clean room," Mike Moreau, deputy project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said in an agency press release(opens in new tab).
Scientists are interested in samples from Bennu and asteroids like it because of their potential to hold clues to planetary formation processes and even, potentially, molecular evidence for the precursors to life. Meteorite samples found on Earth are useful for this type of research, but only to a point. Asteroid material collected in space is free of any Earthly contamination and contains particles smaller than those that survive on space rocks that zoom through our planet’s atmosphere.
To protect the incoming Bennu material from any terrestrial micro-invaders, NASA teams are taking extensive measures and making sure they are prepared well ahead of time. Over the next six months, NASA and Lockheed Martin crews will practice step-by-step procedures for recovering and transporting the OSIRIS-REx sample from a 37-mile by 9-mile (59 by 15 kilometers) landing area inside a Department of Defense property in the Utah desert to NASA’s Johnson Space Center (JSC) in Houston.
Upon landing, the return capsule will be transported to a mobile clean room, where technicians will then unpack the vessel’s heat shield and protective exterior to reveal the sealed container of recovered Bennu material. Ground samples will also be taken from OSRIS-REx’s touchdown location, to test against any contamination risk during landing. Once brought to JSC, a careful unpacking procedure will be observed, which is also being rehearsed leading up to OSIRIS-REx’s arrival.
"These accomplishments are the direct result of the extensive training and rehearsals that we performed every step of the way. We are bringing that level of discipline and dedication to this final phase of the flight operations," said OSIRIS-REx principal investigator Dante Lauretta.
Once unpacked, a fourth of the recovered material will be designated for the OSIRIS-REx researchers. The rest, NASA says, will be reserved for "other scientists to study, now and in future generations."
Science: Is NASA Done Sending Traditional Rovers to Mars?
In February 2021, NASA landed a $2.7 billion rover on Mars that has been roaming the Red Planet ever since. The space agency got what it paid for, as the largely autonomous Perseverance rover has been dutifully collecting rock core samples from Mars and storing them for the first sample return mission from another planet.
Perseverance was the fifth rover of its kind to be sent to Mars, but in terms of NASA’s future robotic exploration of Mars, the space agency is leaning towards launching a series of lower-cost, sustainable missions once every two years, as opposed to developing hugely expensive rovers for the Red Planet.
During a meeting at the National Academies’ Space Studies Board on Thursday, NASA’s Director of the Mars Exploration Program Eric Ianson unveiled the space agency’s long-term strategy for exploring Mars, titled “Exploring Mars Together” that highlighted what’s next after the sample return mission, SpaceNews reported.
“We wanted to look two decades into the future as far as what are the things that we can do to create equally dramatic and profound science [as Mars Sample Return],” Ianson is quoted as saying. “What we’re proposing to do here is to do it at lower cost and a higher cadence of missions.” He projected that those low-cost missions would be between $100 million to $300 million each.
Should the proposed draft strategy be accepted as doctrine, it can be said that NASA will end the era of high-end Mars rovers with a bang; it does not get more complex than Mars Sample Return. The mission is a joint effort between NASA and the European Space Agency, and it includes an orbiter, lander, two helicopters, and a rocket. Working together, this fleet will retrieve rock samples that have been stowed away by the Perseverance rover on Mars.
Moving forward, however, the space agency wants to keep it simple. “Historically we’ve had peaks and valleys in the Mars program,” said Ianson during the meeting, according to SpaceNews. “When we talk about sustainability, it’s something that can be constant throughout. We want to try and maintain missions on a regular cadence.”
That is until NASA tries to land humans on Mars for the first time. The space agency is focused on its Moon to Mars objectives, a proposed idea to use the Moon as a testbed to eventually land humans on Mars, including the use of NASA’s Space Launch System rocket for deep space exploration. With the prospect of landing humans on Mars, NASA no longer seems interested in developing increasingly complex robots for the Red Planet. Which actually makes sense.
NASA’s rover missions usually came one right after the other. The Curiosity rover, Perseverance’s predecessor, landed on Mars in August 2012 and NASA began developing its Mars 2020 rover mission the following year. But now, the agency’s “Future” tab on its Mars Exploration website includes a section for the Mars Sample Return mission and another section for “Humans on Mars,” indicating that another signature Mars rover mission is currently not in the books.
This could very well be the end of a legendary era for NASA’s Mars exploration program. The robotic Martian explorers have provided some major insights on the history of Mars and the potential for the discovery of ancient microbial life on another planet, plus a few iconic selfies during their journey. I guess a human selfie on Mars could be pretty cool too, but those humans will have some big, robotic shoes to fill.
Source: https://gizmodo.com/nasa-expensive-rovers-mars-perseverance-curiosity-1850288783
How Mars lost its magnetic field — and then its oceans
The surface of Mars is barren and dry, with what little water there is tied up in icecaps or perhaps existing below the surface. But look closely at the surface, and you will see what looks like shorelines or canyons where massive floods once took place.
Billions of years ago, the atmosphere of Mars may have been denser and the air slightly warmer. By looking at deltas present on Mars, similar to river deltas on Earth, some have suggested that oceans used to partially cover the planet. (See Strange Map #1043.) Others have looked at the composition of Mars meteorites, which can show how the chemistry of Mars today compares to what the planet looked like billions of years ago. Both lines of evidence suggest that about four billion years ago, Mars’ northern hemisphere was covered with a massive ocean.
Today, this ocean is just a memory. Recent research led by the University of Tokyo and published in Nature Communications explains one reason why: Billions of years ago, Mars lost its magnetic field. Without the protection that a magnetic field offered, the atmosphere was stripped, and eventually, the oceans evaporated as water vapor in the atmosphere was lost to space.
Magnetic fields and oceans
The solar system is a harsh place. Our life-giving Sun can also take life away. The Sun produces enormous amounts of radiation that — were it not for the protective effect of our magnetic field — would fry our planet. Without the magnetic field, the solar wind would strip our atmosphere, and the oceans would evaporate and be lost to space. In other words, Earth would end up like Mars.
The Earth is the only one of the rocky planets in our solar system to have a strong magnetic field. Its presence is likely one of the major reasons why Mars and Earth are so vastly different. But billions of years ago, Mars too had a strong magnetic field. So, what happened?
How Mars lost its magnetic field and oceans
To investigate, a team led by Shunpei Yokoo of the University of Tokyo simulated the core of Mars in a lab here on Earth. The team made a material using a mixture of iron, sulfur, and hydrogen, which are believed to be present in the core of Mars.
Sulfur is probably in the core, since Mars meteorites (which sample the crust and mantle) do not contain many elements typically found alongside sulfur. Hydrogen may be plentiful in the core since Mars is close to the “snow line” in our solar system, where water ice was abundant during planet formation. “We can reasonably assume that it [the core] is Fe-S-H liquid but needs to be verified by further marsquake (Martian earthquake) observations,” Yokoo told Big Think. “The ongoing NASA’s InSight mission might tell us more in the near future.”
The team then placed this iron, sulfur, and hydrogen mix between two diamonds and heated it with a laser, simulating the high temperatures and pressures present within the core of a rocky planet. The material separated into two distinct liquids — one with iron and sulfur, the other with iron and hydrogen. Because the liquid containing hydrogen was less dense, it rose to the top. And as the liquids separated, convective currents formed.
This is similar to what would have happened in the early history of Mars. The iron-sulfur-hydrogen liquid would form convective currents as the sulfur separates from the hydrogen. These currents would have formed a protective magnetic field around the planet. But such currents are short-lived. As soon as the two liquids fully separated, the currents would stop, and the magnetic field would vanish. Eventually, the atmosphere would be stripped and the oceans would disappear.
Similar physics in the Earth’s core
This separation of iron-sulfur and iron-hydrogen liquids is also seen within the Earth, but with a key difference: temperature.
“The temperature of the Earth’s core (~6,740 F°) is much higher than that of Mars’ core,” Yokoo told Big Think. At these high temperatures, the iron-sulfur and iron-hydrogen liquids mix together. However, we do see stratification higher in the core, where the temperatures are lower. “This is the reason why the Earth’s core is stratified only at its top, while Mars’ core is entirely stratified,” Yokoo said. “It should take a very long time (like one billion years) for the Earth’s core to be fully stratified.”
We’ve got time, in other words.
These results, however, have implications in the search for habitable exoplanets. Routinely, a key metric to determine if an extrasolar planet can host life is for liquid water to be able to exist on the surface, in a location that is neither too cold nor too hot. But perhaps, a strong magnetic field should be another key metric to determine if the planet can hold onto its water. And it may very well be that magnetic fields as strong as the Earth’s are relatively rare in the Universe.
 |
Virus-free. www.avast.com |
Astronomer’s delight: Earth-sized planet around nearby star is astronomy dream come true – likely to be the focus of future interstellar voyages
Proxima Centauri, the star closest to the Sun, has an Earth-sized planet orbiting it at the right distance for liquid water to exist. The discovery, reported today in Nature1, fulfils a longstanding dream of science-fiction writers — a potentially habitable world that is close enough for humans to send their first interstellar spacecraft.
“The search for life starts now,” says Guillem Anglada-Escudé, an astronomer at Queen Mary University of London and leader of the team that made the discovery.
Humanity’s first chance to explore this nearby world may come from the recently announced Breakthrough Starshot initiative, which plans to build fleets of tiny laser-propelled interstellar probes in the coming decades. Travelling at 20% of the speed of light, they would take about 20 years to cover the 1.3 parsecs from Earth to Proxima Centauri.
How a science-fiction story about our nearest neighbour became a reality
Proxima’s planet is at least 1.3 times the mass of Earth. The planet orbits its red-dwarf star — much smaller and dimmer than the Sun — every 11.2 days. “If you tried to pick the type of planet you’d most want around the type of star you’d most want, it would be this,” says David Kipping, an astronomer at Columbia University in New York City. “It’s thrilling.”
Earlier studies had hinted at the existence of a planet around Proxima. Starting in 2000, a spectrograph at the European Southern Observatory (ESO) in Chile looked for shifts in starlight caused by the gravitational tug of an orbiting planet. The resulting measurements suggested that something was happening to the star every 11.2 days. But astronomers could not rule out whether the signal was caused by an orbiting planet or another type of activity, such as stellar flares.
Star and planet align
In January 2016, Anglada-Escudé and his colleagues launched a campaign to nail down the suspected Proxima planet. ESO granted their request to observe using a second planet-hunting instrument, on a different telescope, for 20 minutes almost every night between 19 January and 31 March. “As soon as we had 10 nights it was obvious,” Anglada-Escudé says.
The team dubbed the work the ‘pale red dot’ campaign, after the famous ‘pale blue dot’ photograph taken of Earth by the Voyager 1 spacecraft in 1990. Because Proxima is a red-dwarf star, the planet would appear reddish or orangeish, perhaps bathed in light similar to the warm evening tints of Earth.
Although the planet orbits at a distance that would permit liquid water, other factors might render it unlivable. It might be tidally locked — meaning that the same hemisphere always faces the star, which scorches one side of the planet while the other remains cool. The active star might occasionally zap the planet with destructive X-ray flares. And it’s unclear whether the planet has a protective, life-friendly atmosphere.
Proxima itself belongs to the triple-star system Alpha Centauri. In 2012, a Nature paper reported that an Earth-mass planet orbited another member of that stellar trio, Alpha Centauri B2. That result has now mostly been dismissed3,4, but exoplanet specialists say the Proxima claim is more likely to hold up.
“People call me Mr Sceptical, and I think this result is more robust,” says Artie Hatzes, an astronomer at the Thuringian State Observatory in Tautenburg, Germany.
False alarm
This time, the combination of new observations and older measurements dating back to 2000 increases confidence in the finding, Anglada-Escudé’s team argues. “It’s stayed there robustly in phase and amplitude over a very long time,” says team member Michael Endl, an astronomer at the University of Texas at Austin. “That’s a telltale sign of a planet.” The data even contain hints that a second planet may exist, orbiting Proxima somewhere between every 100 and 400 days.
The researchers now hope to learn whether the Proxima planet’s pass across the face of its star can be seen from Earth. The chances are low, but such a ‘transit’ could reveal details of the planet, such as whether it has an atmosphere. A team led by Kipping has been independently looking for transits around Proxima, and is frantically crunching its data in search of any signal.
The discovery of the Proxima planet comes at a time of growing scientific interest in small planets around dwarf stars, says Steinn Sigurdsson, an astrophysicist at Pennsylvania State University in University Park. NASA’s Kepler space telescope has shown that rocky planets are common around such stars, which themselves are the most common type of star in the Galaxy. “This is a total vindication of that strategy,” he says.
One day, the Proxima planet might be seen as the birth of a new stage in planetary research. “It gives us the target and focus to build the next generation of telescopes and one day maybe even get to visit,” says Kipping. “It’s exactly what we need to take exoplanetary science to the next level.”
Science: Five Fascinating Ice Age Finds Discovered in Yukon Permafrost
From a pristinely preserved wolf pup to ancient camels, remains found in northern Canada’s frozen earth have provided remarkable glimpses into the Ice Age
Rachael Lallensack
Assistant Editor, Science and Innovation
February 7, 2022
Frozen ground preserved the body of this seven-week-old wolf pup, which lived during the Ice Age. Government of Yukon
In Canada’s Yukon territory, towering pine and spruce forests drape over rolling hills and the Yukon River and its winding tributaries cut valleys into the landscape. Winters in this northwest corner of Canada are harsh, but the warm summer months are illuminated by sunshine until midnight.
Even further north, however, rests the treeless alpine tundra where frigid temperatures permanently keep the ground frozen. The icy soil is called permafrost. For the most part, only moss, lichen and shallow-rooted shrubs can grow in the tundra.
Though moose outnumber people by almost twofold, the Yukon has a bustling mining industry and 14 First Nations groups have thrived on the land for thousands of years. They are descended from the last waves of ancient people who journeyed over the Bering Land Bridge from what is now Siberia at least 15,000 years ago—before the crossing flooded at the end of the last glacial period.
Commonly known as the last Ice Age, the last glacial period began about 100,000 years ago. During this time, most of North America was covered in glaciers, but conditions in what’s now the Yukon were too dry for glaciers to form. Because most of the world’s water was locked up in ice, sea level is estimated to have been as much as 500 feet lower than it is today. This revealed the floor of the Bering Sea, creating a passage between Alaska and Siberia known as Beringia.
Ancient animals made the journey tens of thousands of years before humans, and the Yukon became a vibrant home for giant creatures known as megafauna. Wooly mammoths migrated to North America from Europe and Asia, and generations of Ice Age horses originating in North America may have crossed the land bridge more than once. Giant ancestors of camels, sloths, lions, hyenas and many others populated the landscape. When these animals died, their bodies likely decomposed, and anything that wasn’t scavenged became part of the frozen ground.
Permafrost’s cool touch perfectly preserves nearly anything within it, including DNA. Ancient genes can be easily extracted from bones and soft tissue, and scientists have even found intact genetic material in soil samples.
Today, scientists know how these animals lived and died because their bones and bodies are so well-preserved in permafrost. First Nations people have deep historic knowledge of Ice Age animals as well as their fossils. Likewise, since the Klondike Gold Rush at the turn of the 20th century, miners have uncovered many gargantuan bones—Ice Age relics that continue to be found en masse at mines and river banks today. As climate change advances, permafrost is also thawing rapidly and releasing its contents—a gold rush of sorts for paleontologists.
Here are five fascinating finds that paint a picture of the Yukon’s past.
Zhùr, a mummified wolf pup who lived some 57,000 years ago, was found by a miner in Canada’s sparsely populated Yukon territory, where permafrost has preserved remarkable paleontological finds for millennia. Government of Yukon
What makes this find remarkable: "She’s the most complete wolf mummy that’s ever been found. She’s basically 100% intact—all that’s missing are her eyes,” study coauthor Julie Meachen, a paleontologist at Des Moines University in Iowa, said in a press release.
What scientists have learned: In 2016, a gold miner blasting a hydraulic water cannon at frozen mud discovered an object paleontologists recognized as a treasure. He’d unearthed a near-perfectly preserved female gray wolf pup that died 57,000 years ago. The Ice Age animal was found on the ancestral land of the Tr’ondëk Hwëch’in people, who named her Zhùr, which means wolf in Hän.
X-rays of her bones and teeth showed she was just under seven weeks old when she died, according to a study published in Current Biology. Scientists ruled out starvation or predator attack as causes of death because she was so pristinely preserved. Instead, they concluded that a den collapse likely killed Zhùr.
Further analysis shows her diet was fish-heavy, which suggests she may have hunted with her mother along rivers as modern wolves do today. Genetic data suggests Zhùr had distant relatives in Eurasia and Alaska. However, wolves living in the Yukon today have a different genetic signature, which means Zhùr’s population was eventually wiped out and replaced by another.
While burrowing animals from this era like arctic ground squirrels and black-footed ferrets have also been found in similar condition, “Mummified remains of ancient animals in North America are incredibly rare,” says Zazula in a statement. “Studying this complete wolf pup allows us to reconstruct how this wolf lived during the Ice Age in ways that would not be possible by looking at fossil bones alone.”
Zhùr is on display at the Yukon Beringia Interpretive Center in Whitehorse.
Western Camel Bones
Scientific name: Camelops hesternus
Western camels’ Latin name, Camelops hesternus, translates to “yesterday’s camels” in Latin Yukon Beringia Interpretive Centre
What makes this find remarkable: The bones rearranged the Camelidae family tree by providing concrete evidence that the animals were closely related to modern camels instead of llamas, according to a 2015 study published in Molecular Biology and Evolution.
What scientists have learned: The camel family, Camelidae, actually originated in North America more than 40 million years ago. Their lineage eventually split into camels and llamas. Ancestors of the dromedary and Bactrian varieties familiar today migrated across the Bering Land Bridge, while predecessors of llamas and alpacas moved to South America.
Meanwhile, now-extinct western camels (Camelops hesternus, which translates to “yesterday’s camels” in Latin) stayed in North America until the end of the Ice Age. While most of them ventured south, even as far as Honduras, some made their way north to Alaska and the Yukon.
Camelops bones
Camelops hesternus bones found in the Yukon photographed from different angles. Heintzman et. al, Molecular Biology and Evolution, 2015
For many decades, scientists hypothesized Arctic-dwelling camels were more closely related to llamas and alpacas native to South America because C. hesternus bones resembled a “giant llama” or “llamas on steroids,” says paleontologist Grant Zazula, who works for the Yukon territory.
In 2008, gold miners in Hunker Creek, which is about 60 miles away from the Alaskan border, collected a pile of Ice Age-era bones that date back 75,000–125,000 years. A few peculiar specimens turned out to be several leg bones belonging to an extinct camel species whose remains are rarely found that far North. The bones were so well-preserved in the cold conditions that researchers were later able to extract DNA.
The genetic data showed Ice Age western camels split off from modern-day camels around ten million years ago. Ancestors of today’s camels migrated across Beringia about seven million years ago. The Arctic’s western camels likely traveled north from their typical range during a warmer period about 100,000 years ago before going extinct about 10,000 years ago.
Arctic Hyena Teeth
Scientific name: Chasmaporthetes
Ancient hyena likely found their way into North America via Beringia, the land bridge that existed between Russia and Alaska during various periods known as glaciations, when much of the world’s water was contained in glaciers instead of in the ocean. Julius T. Csotonyi
What makes this find remarkable: "[There have] been over 50,000 bones of ice-age animals found in the Old Crow area in the past, and we only have two bones or two teeth of this hyena," Zazula told the CBC in 2019. "So it’s a very rare animal. It was almost like a needle in a haystack."
What scientists have learned: When most people think of hyenas, they likely picture the stout and scrappy scavengers living in African savannas or arid parts of India. The ancestors of the cackling creatures likely resembled today’s hyenas but had tall, powerful legs for running fast. Chasmaporthetes actually evolved in what is now Europe or Asia more than 5 million years ago, and their remains have been unearthed all over the world, including in Mongolia, Kansas, Mexico—and now, the Yukon.
A fossilized pair of teeth stored in the Canadian Museum of Nature in Ottawa were suspected to be evidence of hyenas living in the ancient Arctic, but a formal analysis wasn’t completed until 2019.
When evolutionary biologist Jack Tseng, who specializes in prehistoric carnivores, finally got to study the teeth in person, he knew “within five minutes” that the molar and premolar indeed belonged to Chasmaporthetes.
Scientists first found the fossilized teeth that now reside at the museum in the 1970s near Old Crow. Charlie Thomas, an elder of the Gwich’in First Nations community, was part of the group to discover them.
Chasmaporthetes tooth
Recent research determined that this tooth, originally discovered in 1977, belonged to the ancient hyena Chasmaporthetes. Grant Zazula / Government of Yukon
Because they were found in a riverbed and not in their original resting place, the teeth are difficult to date. However, based on geology of the basin, researchers estimate the teeth belonged to a hyena that prowled between 850,000 and 1.4 million years ago.
Like today’s hyenas, the ancient arctic beast had a mouthful of chompers perfectly suited for crushing the bones of its prey, which were probably ancient caribou, young bison or maybe even baby mammoths. As for why they went extinct, researchers suspect other Ice Age predators, like the short-faced bear or extinct bone-cracking dog, may have outcompeted Chasmaporthetes for food.
Giant Beaver Skull
Scientific name: Castoroides ohioensis
Longer than most humans—save professional basketball and volleyball players—the giant beaver was one of the largest rodents recorded. Canadian Museum of Nature
What makes this find remarkable: “I think any time anyone sees our giant beaver skull, they’re like, ‘Wow, it must have been a sabre-tooth cat and eating people,’” Zazula told Yukon News in 2019.
“No, just pond weeds. It’s almost like, kind of anti-climatic, you know? You have this animal that’s seven feet tall that just eats little pond weeds and you want it to be more dramatic than that, but it’s not.”
What scientists have learned: With a pair of six-inch incisors jutting from its head, the Ice Age giant beaver looked like a fierce predator—but in reality, one of natural history’s largest rodents enjoyed diving for aquatic plants.
At 6 feet long and 220 pounds, Castoroides ohioensis was about the size of a modern black bear. The tail on this massive rodent resembled that of a muskrat more than today’s paddle-tailed Castor canadensis.
A complete Castoroides ohioensis upper incisor from Old Crow, Yukon Territory, Canada
This complete Castoroides ohioensis upper incisor was found in Old Crow. Scientific Reports/Photos by Tessa Plint
But giant beavers weren’t exactly tree-gnawing, dam-building ecosystem engineers like beavers in the Arctic are now. In a 2019 Scientific Reports study, researchers analyzed the chemical signatures in several fossilized bones and teeth found in the Yukon and Ohio estimated to date back between 10,000 and 50,000 years. These tests showed the prehistoric creature preferred aquatic plants.
“Basically, the isotopic signature of the food you eat becomes incorporated into your tissues,” study author Tessa Plint of Heriot-Watt University explained in a 2019 statement. “Because the isotopic ratios remain stable even after the death of the organism, we can look at the isotopic signature of fossil material and extract information about what that animal was eating, even if that animal lived and died tens of thousands of years ago.”
Researchers study the diets of extinct Ice Age megafauna to understand climate change today. These animals thrived in wetter climates and died out 10,000 years ago when it became warmer and drier. They may have been outcompeted by smaller beavers, which also lived during the Ice Age and survived to gnaw on wood today
“It provides a really cool analogue about what’s happening today in the North, because we see animals moving north, north, north all the time now because of warming conditions,” Zazula said to Yukon News.
”…[This migration] happened 100,000 years ago as well,” he continued. “These animals saw these environments moving northward and they followed the environment and ended up in a place where they probably shouldn’t be, like the Yukon, because they’re animals that evolved in more southern conditions.”
Scimitar Cat Bone
Scientific name: Homotherium latidens
What makes this find remarkable: Because relatively few scimitar cat fossils have been found, scientists theorized that only a smaller population of these fanged felines existed, per CBC. This humerus made them reassess.
What scientists have learned: In 2011, a bone was found in permafrost on a Dominion Creek mining site near Dawson City. It belonged to a scimitar cat (Homotherium latidens)—not to be confused with a saber-toothed cat (Smilodon). Scimitar cats have shorter, dagger-shaped canines with serrated edges, unlike their famed relatives, whose teeth typically measured a frightening seven inches long.
However, since the bone was so well-preserved in icy permafrost, researchers at the University of Copenhagen were able to sequence its entire genome. They found that the specimen’s parents were only distantly related, which means the population was large enough to be genetically diverse—more than modern cat species like African lions and lynx, according to a comparative analysis.
A scientific diagram of the scimitar cat, several traits and genes associated with each
In this diagram, researchers match 18 genes with a hypothesized link to a specific behavior, physical trait or adaptation. About a dozen more genes not shown were analyzed and associated with cell function and immunity. It is Figure 2 in the 2020 study. Barnett et. al, Current Biology, 2020
Because so much is known about modern human and animal genetics, researchers can identify certain physical details associated with specific genes and then infer how the ancient creature may have behaved, said study author Thomas Gilbert, an evolutionary genomicist at the University of Copenhagen, in a statement.
“Their genetic makeup hints towards scimitar-toothed cats being highly skilled hunters. They likely had very good daytime vision and displayed complex social behaviors,” said Michael Westbury, an evolutionary genomicist at the University of Copenhagen, in a 2020 statement.
“They had genetic adaptations for strong bones and cardiovascular and respiratory systems, meaning they were well suited for endurance running,” he continued. “Based on this, we think they hunted in a pack until their prey reached exhaustion with an endurance-based hunting-style during the daylight hours.”
Because the bone could not be dated using conventional radio-carbon dating, which can only be used to deduce object ages within a certain range, it’s estimated to be more than 47,500 years old. It likely went extinct around 10,000 years ago when other Ice Age animals, including its preferred prey, also died out. "So you have like the woolly mammoth, woolly rhinos, large North American horses, they all went extinct at the same time," Westbury told CBC.
“This was an extremely successful family of cats. They were present on five continents and roamed the Earth for millions of years before going extinct,” says Ross Barnett of the University of Copenhagen in a 2020 statement. “The current geological period is the first time in 40 million years that Earth has lacked saber-tooth predators. We just missed them.”
Science: Experiments with regrowing Frogs’ Limbs: Humans might be able to regrow limbs one day
Frogs can’t naturally regrow their legs, but a drug cocktail did the trick.
Scientists have regrown frogs’ amputated legs after giving them a "cocktail" of drugs encased in a silicon stump.
African clawed frogs (Xenopus laevis) are like humans in that they can’t naturally regrow lost limbs. In the new study, researchers successfully coaxed the frogs to grow replacement limbs in 18 months following a treatment that lasted just 24 hours. While there’s a massive difference between frogs and humans, the finding raises the possibility that in the future, humans could also regrow limbs.
"It’s exciting to see that the drugs we selected were helping to create an almost complete limb," first author Nirosha Murugan, a research affiliate at Tufts University in Massachusetts, said in a statement. "The fact that it required only a brief exposure to the drugs to set in motion a months-long regeneration process suggests that frogs and perhaps other animals may have dormant regenerative capabilities that can be triggered into action."
Animals have natural abilities to regenerate themselves. For example, human bodies close open wounds and can even use stem cells to regrow parts of the liver. Some animals, such as salamanders, can regrow whole limbs and other missing parts. The mechanisms behind limb regeneration are not fully understood, but neither humans nor adult frogs are capable of regrowing legs and arms, perhaps because those limbs are so complex.
Both humans and frogs cover an open amputation wound in scar tissue to stop further blood loss and infection. Humans have developed prosthetic replacement limbs but scientists have been unable to recover or reverse the loss of a major limb like an arm or leg.
The latest research used multiple drugs to regenerate lost limb tissue. The team surgically amputated frogs’ legs and then applied a silicone cap they called a "BioDome" to each frog’s wound. The cap released a cocktail of five drugs, including growth hormones, that perfomed different roles, such as encouraging nerves and muscles to grow. One of the drugs also prevented the frogs’ bodies from producing collagen, which normally causes wounds to scar over.
"Using the BioDome cap in the first 24 hours helps mimic an amniotic-like environment, which, along with the right drugs, allows the rebuilding process to proceed without the interference of scar tissue," co-author David Kaplan, a professor of engineering at Tufts University, said in the statement.
Embryos and fetuses develop in an amniotic sac during pregnancy. The team was able to trigger some of the same molecular pathways in the frogs that are used when an embryo is growing and taking shape.
The new legs looked similar to normal legs with similar bone structure, except for the toes, which lacked underlying bones. The frogs were able to use their new leg to swim like a regular leg.
The findings were published Jan. 26 in the journal Science Advances.
Science: Massive Hidden water reserves discovered on Mars
A joint European Union and Russian mission has discovered “significant amounts of water” lying just below the surface of Mars – and scientists say it could be “easily exploitable” by future explorers.
Hidden water reserves discovered on Mars
Valles Marineris, seen at an angle of 45 degrees in near-true colour and with four times vertical exaggeration © ESA
The largest canyon in our Solar System, Valles Marineris sits just south of Mars’ equator and is some 10 times longer and five times deeper than Earth’s Grand Canyon. It’s also hiding a body of water the size of the Netherlands, the European Space Agency (ESA) announced on Wednesday.
The water was detected by the ExoMars Trace Gas Orbiter, a joint project of the ESA and the Russian space agency, Roscosmos. The satellite detected a large amount of hydrogen less than a meter below the canyon’s surface, and, as hydrogen molecules bind into water molecules, the discovery indicates the soil in that location is rich in moisture, which probably exists as ice.
Breaking news: I’ve spotted hidden #water – either ice or water-rich minerals ? – in #Mars’ Grand Canyon! ❄️??The reservoir is large, not too deep below ground, & could be easily exploitable for future explorers ?Read on: https://t.co/lIAEuz2tNW#ExploreFarther#ExoMarspic.twitter.com/j1jwSCJebq
— ExoMars orbiter (@ESA_TGO) December 15, 2021
“We found a central part of Valles Marineris to be packed full of water – far more water than we expected,” Alexey Malakhov of the Space Research Institute of the Russian Academy of Sciences wrote. “This is very much like Earth’s permafrost regions, where water ice permanently persists under dry soil because of the constant low temperatures.”
The ESA press release noted that water ice usually evaporates in this region of Mars due to the temperature and pressure conditions near the planet’s equator. The fact that this Netherlands-sized body of water hasn’t suggests either a previously unknown mix of atmospheric conditions or that the water is somehow being replenished.
The discovery isn’t the first sign of water on Mars. Ice caps cover its polar regions, and previous ESA missions have found potential water stores several kilometers beneath its surface. However, the latest find reveals water the ESA says is much more “exploitable,” and makes “Valles Marineris an even more promising target for future human exploration missions to the planet.”
The Trace Gas Orbiter launched in 2016 and began orbiting Mars two years later. The project was originally planned as a collaboration between the ESA and NASA, but the Europeans partnered with Roscosmos in 2012, after US President Barack Obama slashed NASA’s budget. The orbiter will be joined in 2022 by a European rover and a Russian surface platform, as the hunt for past life on the Red Planet continues.
Science: Physicists create new state of matter from quantum soup of magnetically weird particles
Scientists have spotted a long hypothesized, never-seen-before state of matter in the laboratory for the first time.
By firing lasers at an ultracold lattice of rubidium atoms, scientists have prodded the atoms into a messy soup of quantum uncertainty known as a quantum spin liquid.
The atoms in this quantum magnetic soup quickly became connected, linking up their states across the entire material in a process called quantum entanglement. This means that any change to one atom causes immediate changes in all of the others in the material; this breakthrough could pave the way for the development of even better quantum computers, the researchers said in a paper describing their findings Dec. 3 in the journal Science.
Related: 12 stunning quantum physics experiments
"It is a very special moment in the field," senior author Mikhail Lukin, a professor of physics at Harvard University and the co-director of the Harvard Quantum Initiative, said in a statement. "You can really touch, poke, and prod at this exotic state and manipulate it to understand its properties. It’s a new state of matter that people have never been able to observe."
First theorized in 1973 by the physicist Philip Anderson, quantum spin liquids emerge when materials are cajoled into disobeying the usual rules that govern their magnetic behaviour.
Electrons have a property called spin, a type of quantum angular momentum, that can point either up or down. In normal magnets (like the ones people put on the fridge), the spins of neighboring electrons orient themselves until they all point in the same direction, generating a magnetic field. In non-magnetic materials, the spins of two neighboring electrons can flip to oppose each other. But in either case, the tiny magnetic poles form a regular pattern.
In quantum spin liquids, however, the electrons refuse to choose. Instead of sitting next to each other, the electrons are arranged into a triangular lattice, so that any given electron has two immediate neighbors. Two electrons can align their spins, but a third will always be the odd one out, destroying the delicate balance and creating a constantly switching jumble of agitated electrons.
This jumbled state is what the researchers call a "frustrated" magnet. As the spin states no longer know which way to point, the electrons and their atoms are instead thrown into a weird combination of quantum states called a quantum superposition. The ever-fluctuating spins now exist simultaneously as both spin up and spin down, and the constant switching causes atoms all the way across the material to entangle with each other in a complex quantum state.
The researchers couldn’t directly study the ideal quantum spin liquid, so they created a near perfect facsimile in another experimental system. They chilled an array of 219 trapped rubidium atoms — which can be used to minutely design and simulate various quantum processes — to temperatures of roughly 10 microkelvins (close to absolute zero or minus – 273.15 degrees Celsius° Celsius).
Occasionally one of the electrons in an atom is in a much higher energy level than the others, putting the atom in what is known as a Rydberg state. Much like with spin states, the spooky rules of quantum mechanics ensure that an atom does not want to be in a Rydberg state if its neighbor is. By firing lasers at certain atoms within the array, the researchers mimicked the three-way tug-of-war seen in a traditional quantum spin liquid.
Following the creation of their quantum Rydberg soup, the researchers conducted tests on the array and confirmed that its atoms had become entangled across the entire material. They had created a quantum spin liquid.
—The 18 biggest unsolved mysteries in physics
—The world’s most beautiful equations
—The 9 most massive numbers in existence
The scientists then turned their attention to a proof of concept test for its potential application: designing the qubits, or quantum bits, of a quantum computer. While ordinary computers use bits, or 0s and 1s to form the basis of all calculations, quantum computers use qubits, which can exist in more than one state at once. Qubits, however, are incredibly fragile; any interaction with the outside world can easily destroy the information they carry.
But the special nature of the quantum spin liquid’s material-wide entanglement, however, could allow for far more robust information storage. That’s because instead of encoding quantum information into just one qubit, it could allow for information to be contained in the shape — or the topology — that the entangled spin states make throughout the material itself; creating a "topological qubit." By encoding information in the shape formed by multiple parts rather than one part alone, the topological qubit is much less likely to lose all of its information.
The researchers’ proof of concept created only a tiny topological qubit, just a few tens of atoms long, but in the future, they hope to create much larger, more practical ones.
"Learning how to create and use such topological qubits would represent a major step toward the realization of reliable quantum computers," co-author Giulia Semeghini, a quantum physicist at Harvard University, said in the statement. "We show the very first steps on how to create this topological qubit, but we still need to demonstrate how you can actually encode it and manipulate it. There’s now a lot more to explore."
INSANELY AWESOME SCIENCE: Mars Helicopter Just Keeps on Going – The Robot that won’t quit
The original mission of the Mars Helicopter (named Ingenuity) was to successfully complete a single 30-second long flight on Mars. That happened back in April. After several more successful flights, Ingenuity’s 30-day mission came to an end, but the helicopter was doing so well that NASA decided to keep it flying. Several months later, JPL promised that Ingenuity would “complete flight operations no later than the end of August,” but as of late November, the little helicopter has completed 17 flights with no sign of slowing down.
NASA has kept the helicopter operational, in part, because it’s transitioned from a pure technology demonstration to an operations demonstration. In fact, Ingenuity has turned out to be quite useful to both the science team as well as the roboticists who operate the Perseverance rover. While NASA never planned to have Ingenuity make occasional scouting flights, its having that capability seems to have paid off. To understand just how much of a difference the helicopter is making to Perseverance’s mission, we talked to one of the Mars rover drivers at JPL, Olivier Toupet.
Toupet has been at JPL for nine years, and he’s the supervisor of JPL’s Robotic Aerial Mobility group (which includes key members of the Mars Helicopter team). He’s also the deputy lead of the rover planner team for Perseverance, meaning that he’s one of the folks who tells the rover where to go and how to get there. In his role as a Perseverance rover driver, Toupet specializes in strategic route planning, which means listening to where the scientists want the rover to go and thinking about how to best reach all of those targets while considering things like safety and longer term goals. “We design routes to visit the targets that scientists are interested in, or we tell them that it’s too dangerous,” Toupet tells us.
“Initially there was a lot of pushback, even from the science team, because they thought it was going to be a distraction. But in the end, we’re all very happy with the helicopter, including the science team.”
—Olivier Toupet, NASA JPL
Toupet was also one of the rover drivers on the Mars Exploration Rovers (MER) and Mars Science Laboratory (MSL) programs, and over the years, he and his team have developed a solid intuition about how to drive Mars rovers over different types of terrain—how to do it efficiently, but also minimizing the chances that the rover could get damaged or stuck. Obviously, the stakes are very high, so the rover team takes no chances, and sometimes having even a single picture from Ingenuity of a potential route can completely change things, says Toupet.
IEEE Spectrum: How much of a difference has it made for you to have Ingenuity scouting for Perseverance on Mars?
Olivier Toupet: My team designs the routes for the rover to drive, and typically we have orbital imagery [from Hi-RISE], which is as you can imagine very low resolution, and then we have imagery from the rover on the surface, but it can only see a few hundred meters. With the orbital imagery, we can’t see rocks that are smaller than typically about a meter. But a rock that is taller than 35 centimeters is an obstacle for the rover—it can’t put its wheel over a rock that size. So it’s been really helpful to have that helicopter imagery to refine our strategic route and plan to avoid challenging terrain well before the rover can see it."
Animated gif cycling between blurry orbital imagery, less blurry rover imagery, and high resolution helicopter images This animation shows the different kinds of imagery that the rover planners are able to use for route planning, including imagery from the rover’s own cameras, images taken from orbit, and helicopter images.NASA/JPL
What about planning for day-to-day rover operations?
We do look at the helicopter images when planning our daily drives, but we can’t fully trust the 3D mesh obtained from pairs of overlapping images because we don’t know the exact distance the helicopter flew in between each one. We use the images in a qualitative way, but we can’t tell where obstacles are with the precision that we’d need for drive planning—we can’t entrust the life of the rover to those images.
You and your team must be highly skilled at understanding Martian terrain from the relatively low-resolution orbital images, since JPL has been planning for rovers on Mars based entirely on orbital images for decades now. With that in mind, how actually useful is high-resolution imagery like the helicopter provides?
I was actually a rover planner on Opportunity, Curiosity, and now Perseverance, so I’ve been doing this for a long time! But it’s a fair question. You are correct that we’re very experienced with interpreting orbital imagery, but there are still some cases where higher resolution imagery can be very important. With Curiosity, there’s a place called Logan Pass, where of course we had relied on orbital imagery for our strategic route planning.
Panoramic image of the Mars surface showing a sandy depression with hills and mountains in the background View southeastward towards Logan Pass from Curiosity’s Mast Camera, taken in May of 2015.NASA/JPL-Caltech/MSSS
We thought there was a shortcut to get there that we could squeeze through. We drove all the way there to the start of a slope that we were going to have to drive on with a large field of sand dunes beneath it. We’d thought that the slope was likely to be compacted sand, which would have been fine, but what we couldn’t see on the orbital imagery was that the slope was actually a thin layer of sand on top of pebbles, and when the rover tried driving on it, it began to slip substantially down towards the sand trap. We tried to get across the slope a couple of times, but we ended up deciding that it wasn’t safe at all, so we had to take a pretty substantial detour because that strategic route wasn’t feasible.
Curiosity’s path shown as a white line which goes into a dead end and out again Orbital imagery of Curiosity’s route showing attempt to traverse Logan Pass, followed by detour through Marias Pass.NASA
So overall, it’s true that typically orbital imagery is good enough, especially on terrain that’s pretty benign. But there are times where having higher resolution imagery ahead of time is very valuable for route planning.
What about for Perseverance? Are there any examples of specific ways in which detailed imagery from Ingenuity caused you to change your mind about a route?
We landed right next to an area called Séítah, which is actually very hard to drive through because it’s full of large sand dunes. And getting stuck in sand is the nightmare of every rover planner, because it could be mission-ending. Right after landing, the scientists were saying, “let’s cross over Séítah and get to the delta!” I said, that’s not going to happen, we have to drive around it.
Orbital image showing Perseverance’s route as a white line traveling around an area of hills and sand dunes View of Perseverance’s route around Séítah and current position of the rover and helicopter on the south side of Séítah.NASA
While we were driving around, the helicopter just flew right over to the west side of Séítah on Flight 9. That was really interesting, because it gave us excellent images and we realized that while there were some places we wouldn’t want to drive in, there were other places that actually looked traversable.
Image of the sandy, rocky surface of Mars, with the shadow of the Mars helicopter in flight at the bottom Image taken by Ingenuity showing bedrock poking through sand, suggesting that some areas might be traversable by the Perseverance rover.NASA/JPL-Caltech
And so it was really helpful to have that helicopter imagery over Séítah to refine our strategic route. Thanks to the helicopter, we ended up modifying our route—we were initially going to drive over a kind of hill, but the helicopter flew right above that hill, and I was able to see that the hill looked much more challenging than I thought from the orbital imagery. In the end, we decided to drive around it.
Aerial image of a hill on Mars showing a red line labeled "Initial Route" going over the hill and a green line labeled "Refined Route" going around the hill Image taken by Ingenuity of the hill Perseverance had planned to climb, which helped the rover planning team decide to drive around the hill instead.NASA/JPL-Caltech
If we hadn’t had the helicopter imagery, I think we would still have made it work and found the same route. But having the helicopter, we were able to plan the route ahead of time, and make a much better estimate of how long it would take, which helps the whole Perseverance rover team to plan more efficiently. That’s pretty valuable.
What has the reaction been to having the Mars Helicopter stick around as a scout?
The whole team, we all love it! We didn’t know we were going to love it—it’s really interesting, I think initially there was a lot of pushback, even from the science team, because they thought it was going to be a distraction. But in the end, we’re all very happy with the helicopter, including the science team. The more information we have the better—for the science team, for example, the helicopter can save us a lot of time by quickly investigating potentially interesting areas.
“We’ve found a way to do both rover and helicopter activities in parallel, in a way that’s very low impact and very high value.”
—Olivier Toupet, NASA JPL
For example, when we flew the helicopter over Séítah, over the area where the scientists wanted the rover to go, the pictures that the helicopter took enabled the scientists to decide whether it was even worth trying to drive the rover that far—it would have taken us two or three weeks to even get there. But the images from the helicopter led the scientists to say, “hey, yeah, this area is actually really interesting, and we see valuable rocks that we’d like to go and sample. And so it enabled us to make that decision early on rather than potentially wasting two to three weeks driving over there for nothing.
At one point, JPL said that even if everything with the helicopter was working great, flight operations would cease “no later than the end of August.” Obviously, the helicopter is still flying—how much of a surprise has that been?
Frankly, it’s been a big surprise, but we should have known better! Opportunity was supposed to be a 90-day mission, and it was still going 14 years later. Some of us suspected that the helicopter mission would continue to be extended, but the helicopter team played their cards pretty close to their chest. Obviously, they were very focused on accomplishing the tech demo, and that was always a top priority. So whenever we’d ask, “what happens next,” they’d tell us not to get distracted because a successful tech demo was why the helicopter was funded to go to Mars.
But I remember being in a meeting with someone from NASA HQ, who said something that is very true, which was that the tech demo is great, but the long-term goal is to show the potential of flying on Mars. I really hope that Ingenuity being such a success means that in the future there will be another helicopter mission to Mars. You can imagine a helicopter flying into Vallis Marineris, the largest canyon in the solar system. It would be amazing.
The official story was always that there were going to be five flights and that was probably going to be the end, and so I’m glad that we’re now at flight 17, and the helicopter has been extremely successful. I can’t wait to see all the things we’ll be able to do in the months to come, including when we reach the delta—there are many steep slopes, and lots of dunes, so having the helicopter there is going to be especially valuable.
Black and white image taken from orbit giving a 3D effect of an ancient river delta Oblique view of the Jezero crater delta looking west.NASA/MSSS/USGS
Do you think that part of the reason that the mission keeps getting extended is because NASA is realizing just how valuable having a helicopter scout can be for a rover like Perseverance?
Yes, I think maybe we didn’t initially realize just how useful the helicopter would be in supporting our scientific mission. I would also say that another reason the helicopter mission keeps getting extended is because it’s turned out to have a fairly minimal impact on the rover team, in the sense that the helicopter team has been pretty independent and they are only flying once every two to three weeks. We’ve found a way to do both rover and helicopter activities in parallel, in a way that’s very low impact and very high value.
It sounds like having a helicopter scout would make an especially big difference once Perseverance reaches the delta. Are you hoping Ingenuity will survive that long, and that it’ll be able to scout for the rover indefinitely?
I definitely hope so! Initially, there were some concerns about whether the helicopter’s electronics will be able to survive the winter [through March of next year]. There are still some questions about this, but things are looking promising. There are also communications challenges—so far, the helicopter has been staying pretty close to the rover, within about 300 meters. But once we’re done with this area to the southwest of Séítah, the rover will be driving very quickly back around Séítah to the foot of the delta. Specifically, we’ll be using multi-sol autonav, which is where we tell the rover to keep on driving itself autonomously as quickly as it can to its destination over multiple Martian days. Put the pedal to the metal! And so there is a little bit of concern whether the helicopter can keep up with us. It’s funny, I love the helicopter, but I also work on the autonav software, so I hope the rover goes fast.
Orbital image of Jezero crater with a dotted yellow line taking a winding kilometers-long route around craters to a location called Three Forks. Perseverance’s planned route from Séítah to Jezero’s river deltaNASA
But I think it’s going to be fine. The helicopter team is working on improved capabilities, including the capability to pop up in the sky and talk to the rover, and that could substantially improve the communications range, perhaps even to kilometers. So while they’re going to do their best to try and keep up with the rover, in parallel they’re working on improving the capability of the helicopter to stay in communications even from farther away. So I’m very hopeful that Ingenuity will be around for a long time!
As someone who’s been working on several generations of Mars rovers, what would you like to see from the next-generation Mars helicopter?
The big advantage of a helicopter is of course that it can fly, and the Mars Science Helicopter will be able to fly tens of kilometers in a single day. To give you a sense of perspective, we’re hoping that Perseverance will be able to drive a few hundred meters in a day. So the helicopter would have several orders of magnitude more range, which is amazing—you could imagine going not just to one site on Mars, but to multiple sites.
A rendering showing on right the Ingenuity Mars Helicopter, 0.5m across, next to the Mars Science Helicopter concept, which has six rotors and is six times the size. Mars Science Helicopter concept compared to Ingenuity.
But the big disadvantage of the helicopter, unfortunately, is the payload. A rover can carry a lot of science instruments, while the helicopter, because the air density is so low on Mars, has a much lower maximum payload, which restricts how much science you can do. That being said, you could imagine being able to swap instruments—what if you could carry just the instrument that was necessary for the specific site you’re visiting that day? Of course there are technical challenges with that, but yeah, personally I do think that the next mission should be a helicopter just by itself. It would be great to see that in the future.
And when we send another rover to Mars, should it have its own helicopter scout?
That’s a great question, and a controversial one, because the next mission to Mars is about sample return, and the European Space Agency is making the rover, not NASA. And so, I don’t know who gets to make such decisions, but I personally do think that a helicopter would be extremely valuable—not just as a scout, but potentially also as a backup, that could retrieve the samples if the rover had some issues. That would be great to have for sure.