Hubble Space Telescope Spots Oldest and Farthest Star Known

Its light twinkled some 900 million years after the Big Bang, astronomers say.

Star light, star bright, how far you look tonight.

Astronomers announced on Wednesday the discovery of the farthest and oldest star ever seen, a dot of light that shined 12.9 billion years ago, or just 900 million years after the Big Bang that gave birth to the universe.

That means the light from the star traveled 12.9 billion light-years to reach Earth.

The finding was part of efforts using the Hubble Space Telescope to search for some of the universe’s farthest and earliest galaxies. By a lucky coincidence, the astronomers were able to discern a single star system within one of those galaxies.

“It was an unexpected surprise to find something so small,” said Brian Welch, a graduate student at Johns Hopkins University in Baltimore who is an author of a paper published Wednesday in the journal Nature that describes the discovery.

Usually, objects that far away are much too dim to be seen. But Einstein’s theory of general relativity, which describes how gravity bends space, offers a handy workaround. A massive galaxy cluster fairly close to us can act as a lens to amplify light from much more distant stars and galaxies behind it.

A survey using the Hubble Space Telescope has been examining 41 galaxy clusters. “When you look at a bunch of really massive galaxy clusters, there’s a good chance that you can find some really highly magnified objects behind them,” Mr. Welch said.

Learn More About the James Webb Space Telescope

After traveling nearly one million miles, the James Webb Space Telescope arrived at its destination. It will spend years observing the cosmos.

•  In Orbit: Now that the telescope has reached its final destination, it will allow scientists on Earth to study ancient galaxies and more.
•  Humanity’s Achievement: “We all share the quest,” our science reporter writes of the observatory’s mission and its significance.
•  The Journey’s Beginning: When the Webb lifted off, it was the culmination of decades of stalled development. Revisit the excitement of the launch.
•  First Glimpses: Two months after the launch, NASA released a series of images recorded by the spacecraft that will help the telescope’s mirrors prepare for scientific research.

The galaxy cluster typically magnifies the brightness of the object behind it by up to a factor of 10, Mr. Welch said.

The light is not magnified evenly, however. Ripples in space-time can create bright spots, much like ripples on the surface of a swimming pool create patterns of bright spots at the bottom of the pool. In examining one of the magnified distant galaxies, the astronomers found that a point of light lined up with one of the ripples, and its shine was magnified by a thousandfold or more.

“The galaxy is sort of stretched out into this long crescent-shaped arc,” Mr. Welch said. “And then the star is just one component of that.”

A wider view of the image that contained Earendel, which was spotted in part because the star was magnified by an effect called gravitational lensing.NASA, ESA, Brian Welch, Dan Coe and Alyssa Pagan

Because the universe is expanding, more distant objects are moving away faster. That shifts the frequency of light toward longer wavelengths. The star spotted by Mr. Welch and his colleagues possesses what astronomers call a red shift of 6.2, far higher than the previous record-holder for most distant single star. That star, reported in 2018, had a red shift of 1.5, corresponding to when the universe was about four billion years old.

The researchers nicknamed the new star Earendel — Old English for “morning star.” If it is a single star, the astronomers estimate that it is a big one — some 50 times the mass of our sun. It could also be a system of two or more stars.

The alignment of Earendel and the galaxy cluster will persist for years, so Earendel will be one of the targets during the first year of observations by the newly launched James Webb Space Telescope, which has a larger mirror than Hubble and gathers light at the longer infrared wavelengths.

The Webb observations will be able to measure the brightness across a spectrum of wavelengths. That will help astronomers determine the star’s temperature. “We really need that spectrum to say with sort of absolute certainty that this is a star as opposed to some other sort of object,” Mr. Welch said.

Mr. Welch said subsequent, more detailed observations by Webb could identify the composition of Earendel. The Big Bang produced only the lightest elements, like hydrogen and helium. The earliest stars are thus expected to contain lower concentrations of heavier elements, which are created by fusion reactions within stars and in the explosions of dying stars. The current hypothesis is that with fewer of the heavier elements, more of the early stars should have been big and bright.

“It looks like it’s pretty hot and pretty massive,” Steven Finkelstein, an astronomer at the University of Texas at Austin who was not involved with the research, said of Earendel.

Yet just this one star would not be enough to prove the case of bigger stars in the early universe. “But it certainly supports that,” Dr. Finkelstein said. “If you start to build up a large number, and many of them look to be pretty massive, then the evidence would get stronger and stronger that more massive stars are the norm in the distant universe.”

The Webb telescope should also be able to find other distant magnified stars like Earendel, although how many are fortuitously lined up with a gravitational lens remains to be seen. It might even be able to spot some of the stars at a red shift between 10 and 20, corresponding to a period between 100 million and 500 million years after the Big Bang.

“Which is right in that window when we think the first stars are forming,” Dr. Finkelstein said.

#Space | https://sciencespies.com/space/hubble-space-telescope-spots-oldest-and-farthest-star-known/

A new place for consciousness in our understanding of the universe

To make sense of mysteries like quantum mechanics and the passage of time, theorists are trying to reformulate physics to include subjective experience as a physical constituent of the world

Physics



30 March 2022

By Thomas Lewton

Pablo Hurtado de Mendoza

A WALK in the woods. Every shade of green. A fleck of rain. The sensations and thoughts bound in every moment of experience feel central to our existence. But physics, which aims to describe the universe and everything in it, says nothing about your inner world. Our descriptions of the wavelengths of light as they reflect off leaves capture something – but not what it is like to be deep in the woods.

It can seem as if there is an insurmountable gap between our subjective experience of the world and our attempts to objectively describe it. And yet our brains are made of matter – so, you might think, the states of mind they generate must be explicable in terms of states of matter. The question is: how? And if we can’t explain consciousness in physical terms, how do we find a place for it in an all-embracing view of the universe?

“There is no question in science more difficult and confusing,” says Lee Smolin, a theoretical physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.

It is also one that he and others are addressing with renewed vigour, convinced that we will never make sense of the universe’s mysteries – things like how reality emerges from the fog of the quantum world and what the passage of time truly signifies – unless we reimagine the relationship between matter and mind.

Their ideas amount to an audacious attempt to describe the universe from the inside out, rather than the other way around, and they might just force us to abandon long-cherished assumptions about what everything is ultimately made of.

Modern physics …

#Physics | https://sciencespies.com/physics/a-new-place-for-consciousness-in-our-understanding-of-the-universe/

U.S. and Russian Astronauts Land on Earth Together Amid War in Ukraine

Mark Vande Hei and two Russian counterparts returned from the International Space Station, where cooperation between NASA and Russia’s space agency continues despite the invasion of Ukraine.

Mark Vande Hei, a NASA astronaut, returned to Earth on Wednesday with two Russian counterparts, landing in Kazakhstan after he spent 355 days in space.

Mr. Vande Hei and his Russian crewmates, Anton Shkaplerov and Pyotr Dubrov, flew home together in a Russian spacecraft, guided by Russian flight controllers. At the landing site, Mr. Vande Hei was met by a contingent of NASA and Russian personnel, a close collaboration between the two space agencies that has continued despite Russia’s deadly invasion of Ukraine and the tensions it has caused between Moscow and the West.

Touchdown on the grassy plain occurred at 5:28 p.m. local time, or 7:28 a.m. Eastern time. Within minutes, three helicopters landed nearby.

The three men emerged in a world where cooperation between Russia and the United States to preserve the future of the International Space Station can no longer be taken for granted.

The space station was meant to be a marvel of peaceful post-Cold War amity between Moscow and Washington, drawing Russia into the community of international collaboration and preventing Russian rocket engineers from selling expertise to countries like North Korea seeking to build better missiles.

In an interview on NASA Television last week, Mr. Vande Hei referred indirectly to the war in Ukraine while discussing the legacy of cooperation in orbit.

“This is a very challenging time for international relations,” Mr. Vande Hei said. “My hope is that in our attempt to further and find peace throughout the world, that these type of connections that we have can be maintained and serve as a path forward.”

But in the past month, Russia has faced withering sanctions, condemnation and growing isolation from Western nations. President Biden harshly condemned President Vladimir V. Putin for the invasion.

NASA has tried to stay above the fray for the past month with minimal statements saying that operations on the space station are unaffected. But the ongoing military conflict could test its ability to continue working with Roscosmos, the state corporation that runs Russia’s space activities.

The Soyuz capsule landed upright, but as often happens, winds dragged the parachute and pulled the capsule over on its side. Within half an hour, recovery teams helped all three astronauts out of the Soyuz.

Mr. Vande Hei was greeted by NASA flight doctors, public affairs officials and representatives from the astronaut’s office and the space station management. Gary Jordan, a NASA spokesman, said that there should be no deviation from the typical process for receiving American astronauts returning on Russia’s Soyuz spacecraft.

The astronauts first sat outside, drinking tea during initial medical tests. Mr. Vande Hei put on a protective mask but took off a pair of sunglasses, commenting that it was a beautiful day. As he and the two Russian crew were carried into an inflatable tent for more medical checks, Mr. Vande Hei spoke with someone on a satellite phone.

Following their stay in the tents the astronauts will take off on a two-hour helicopter flight to an airport, where Mr. Vande Hei and his NASA colleagues will get on a Gulfstream jet and head back to the United States. About 24 hours after landing in Kazakhstan, Mr. Vande Hei will be back in Houston.

While NASA and Roscomos worked together Wednesday to bring their crew members back from orbit, their cooperation was preceded in recent weeks by tense outbursts by Dmitry Rogozin, who leads the Russian space program. He shared a video that suggested the Russians might leave Mr. Vande Hei behind.

NASA officials have carefully sidestepped what Mr. Rogozin has said and insisted that nothing has changed.

“For the safety of our astronauts, the working relationship between NASA and our international partners continues,” Bill Nelson, the NASA administrator, said during his State of NASA speech on Monday. “And that includes the professional relationship between the cosmonauts and our astronauts.”

While NASA remains mum, Scott Kelly, a retired astronaut who held the record for consecutive days in space by an American until Mr. Vande Hei passed it recently, feuded publicly this month with Mr. Rogozin. He stopped at NASA’s request.

At the same time, Russian and European cooperation has all but collapsed since the Russian invasion of Ukraine. The European Space Agency postponed a rover mission to Mars because it relied on a Russian rocket. And a British satellite internet company, OneWeb, canceled a series of launches that used Russia’s Soyuz rockets, shifting some of them to SpaceX rockets. Russia also said it would cease cooperative science experiments with Germany conducted on the Russian part of the space station. A German astronaut, Matthias Maurer, is currently a member of the crew.

Orbital construction of the International Space Station began in 1998 with the launch of the module Zarya. Financed by NASA and built by Russia, it is actually part of the NASA-led half of the space station reflecting American foreign policy at the time, which sought to sustain Russia’s space program during the economic tumult after the collapse of the Soviet Union. Russian and American astronauts permanently moved into the fledging space station on Nov. 2, 2000, and the outpost has been crewed andmanaged by the United States and Russia ever since, with assistance from European, Japanese and other international partners.

#News | https://sciencespies.com/news/u-s-and-russian-astronauts-land-on-earth-together-amid-war-in-ukraine/

The Discovery of Shackleton’s Wreck Is as Disquieting as It Is Amazing

The world today is smaller and less mysterious than when Endurance sank. At the same time, we know too much about the past to be nostalgic.

Sometimes history speaks in rhyme. On March 5, 1922, the polar explorer Ernest Shackleton was buried in a hillside cemetery on the island of South Georgia, in the frigid far southern reaches of the Atlantic. Recently, a team of marine archaeologists announced that it had located the long-sought wreck of his famous ship, Endurance, a three-masted schooner barque that sank off Antarctica more than a century ago. The ship was found on March 5, 2022 — exactly 100 years after Shackleton was laid to rest.

Four days after the discovery, the Falklands Maritime Heritage Trust, which organized the search for Endurance, released a video showing the ship at rest on the ocean floor, nearly two miles below the surface of the Weddell Sea. The images are mesmerizing. A submersible camera circles the wreck, revealing portholes and hatches, a splintered mast, splayed ropes, an anchor chain and, on the deck, the ship’s wheel, which appears almost totally intact. Endurance has become part of the deep-sea ecosystem, encrusted with sponges, sea stars and other organisms. Nevertheless, the boat is remarkably well preserved — a fact attributable, experts speculate, to the absence from cold Antarctic waters of wood-eating creatures like parasitic worms. The most striking shot in the video shows a ghostly white anemone, suctioned to the ship’s transom, above still-glinting lettering that spells the name “ENDURANCE.”

The ship’s story is one of the most illustrious in the annals of exploration. Late in 1914, Shackleton and a crew of 27 sailed south to the Weddell Sea. It was there, early in 1915, that Endurance became trapped in pack ice. The ship drifted amid the floes for more than 10 months before the shifting ice began to crush its hull and the sea finally swallowed it. Shackleton had intended to make the first land crossing of the Antarctic continent; instead, he gained renown for, yes, endurance, braving months stranded on the ice, stormy open-boat voyages and treks across glaciers to ensure that his marooned men would make it home alive. Today, the expedition stands as a parable of astounding courage and the poignancy of dreams not quite realized. The headstone placed at Shackleton’s grave site bears a quotation it attributes to Robert Browning: “I hold that a man should strive to the uttermost for his life’s set prize.”

As sea levels rise, the poles may, in effect, journey to us, swamping our shores.

The discovery of the long-lost ship is a reminder of Shackleton’s deeds. It’s also a lesson in how technology is transforming our encounters with the past. The Endurance video is well-nigh Spielbergian, almost too wondrous, too exquisitely “art directed,” to be believed. Watching it, I couldn’t help imagining what sights we might have beheld had a videographer been present at the opening of King Tutankhamen’s tomb, or if a drone camera were on hand when the jungle cover was stripped back to reveal the citadels of Machu Picchu. We live in a world where real-life “Indiana Jones” scenes may, at any moment, pop up on our social media feeds. But our relationship to these ruins and remnants has changed. These days, a sunken ship inspires not just awe but melancholy, moral unease, even dread.

The Hunt for the Wreck of the Endurance

Battling sea ice and freezing temperatures, a team of explorers and researchers found Ernest Shackleton’s ship that sank in the Antarctic in 1915.

• Historic Moment: The discovery was announced on March 9. The wreck was located at the bottom of the Weddell Sea using undersea drones.
• The Expedition: Endurance22 began its search in February. Researchers studying Antarctic ice and global warming were part of the team.
• Lush Garden: Following the discovery, marine biologists have been scanning footage of the wreck. It could help determine which species live on it, and if any are new.
• From the Archives: Read the cablegram reporting the loss of the ship that Shackleton sent out after making it to safety in the Falkland Islands.

The world today is smaller and less mysterious than in Shackleton’s time. Earth’s remotest realms have given up their secrets. To know the lay of the land in distant places once required literal boots on the ground — in Shackleton’s case, boots with nails punched through the soles, makeshift crampons for clambering over icy peaks. Now, thanks to our conquest of the most distant frontier, outer space, all-seeing satellites provide detailed maps of Antarctica’s ice-sheet moraines, available at the tap of a touch-screen. Journeys once undertaken only by the intrepid — to the depths of the Amazon or the heights of the Himalayas — are on the adventure-tourism circuit. What would Shackleton make of “Journey to Antarctica: The White Continent,” a cruise-ship vacation that offers encounters with icebergs and Emperor penguins amid “the luxury of comfort — a quality of shipboard life and a philosophy of wellness designed to relax and rejuvenate body, mind and spirit”?

Yet we know too much to romanticize the swashbuckling past. The history of exploration, after all, is inseparable from exploitation, the relentless drive of empires and private enterprise to claim territory and expropriate raw materials. The story is ongoing: As natural resources dwindle, global powers are racing to mine new frontiers of the jungles, the oceans, the Arctic north. Antarctica, the world’s last true wilderness, is protected by a treaty, signed by 42 countries, that imposed a ban on resource extraction from the continent, except for scientific research purposes. But nations are jockeying for access to Antarctic fishing, mining and oil reserves — including, most aggressively, China, which has expanded its presence on Antarctica during the pandemic and seems to be preparing for a potential expiration of the mining ban in 2048.

These days, a sunken ship inspires not just awe but melancholy, moral unease, even dread.

Even if the treaty remains in place, all is not well at the bottom of the planet. When Shackleton and his men voyaged to Antarctica, they entered a frozen world. Pictures of Endurance, taken by the expedition’s photographer, Frank Hurley, show the great ship iced into place, high and dry on the ocean’s wintry wastes. The images are iconic; they are also documents of a landship that is vanishing quickly. The Great White South is thawing out. Once, the ice that covered the Weddell Sea made underwater exploration impractical, but in recent months the thickness of that ice has been at some of the lowest levels ever recorded. The discovery of Endurance was aided by climate change.

Other old things are emerging from under ice as the planet heats. Researchers are discovering vestiges of lost worlds, preserved by the now-impermanent permafrost, from tools and weapons of early human societies to the corpses of mammoths and wolves that once roamed the Siberian steppe. Scientists worry that ancient pathogens may be unleashed along with them — that our next pandemic might be a disease that felled our ancient ancestors. Graver still is the vast quantity of carbon, trapped in undecayed plant matter for thousands of years, that is released into the atmosphere as permafrost thaws, creating a feedback loop: temperatures rise, soil melts, gases disperse, temperatures rise further.

In Shackleton’s time, the hardiest adventurers — those strivers to the uttermost — made journeys to the poles. Now, as glaciers dissolve and sea levels rise, the poles may, in effect, journey to us, swamping our shores. When we watch the video of Endurance, we are seeing an artifact of the past, but is it also a portent of the future on our ailing planet? To keep this ship afloat may take a heroic effort.

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​Source photographs: ​Frank Hurley/Scott Polar Research Institute, University of Cambridge/Getty Images; Falklands Maritime Heritage Trust; New York Public Library.

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#Environment | https://sciencespies.com/environment/the-discovery-of-shackletons-wreck-is-as-disquieting-as-it-is-amazing/

Tree cover helps gray foxes coexist with coyotes in the country

As coyotes have spread outside their native range into the eastern United States, they've been known to harass and kill North Carolina's two native species of fox. A new study finds that preserving tree cover may be essential in helping the gray fox survive with coyotes in rural areas, probably because of the fox's unusual ability to climb trees.

In the study, researchers used camera traps to find out where gray foxes coexist with coyotes in suburban, rural or wild areas of North Carolina. Surprisingly, they found gray foxes can coexist with coyotes in suburban forest fragments. However, in rural zones, they avoid areas where coyotes live that lack adequate tree cover.

"Coyotes are well known to persecute smaller foxes," said study co-author Roland Kays, research associate professor at North Carolina State University and director of the NC Museum of Natural Sciences Biodiversity & Earth Observation Lab. "They go out of their way, more than you see in other interactions between species, to really bully, chase and kill the smaller foxes. There is some reason for concern if this species is going to survive. How is that going to happen in an urban environment where you also have people?"

Coyotes have spread across North America from their native range in parts of the western United States, taking advantage of the fact that larger predators -- such as cougars and wolves -- aren't found in most of the eastern U.S. anymore.

"The general trend has been a decline in all carnivores, but there are some exceptions, and the coyote is one of the big exceptions," Kays said.

Researchers wanted to know how coyotes might impact where native species like the gray fox are now found -- especially since urbanization could affect how the two species interact by fragmenting their habitats and disrupting food sources.

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"Foxes are fairly common in urban areas, perhaps in part because coyote numbers are relatively low," said the study's lead author Arielle Parsons, postdoctoral research associate at NC State. "In the Midwest and western United States, there are indications of 'apparent decline' in fox populations concurrent with coyote population increases. We don't know if it's a true decline yet, but there's evidence it is."

The researchers used wildlife photos taken by volunteers to figure out where foxes and coyotes coexist. The photos came from 915 motion-sensitive cameras that volunteers placed in yards, forest fragments and open areas in suburbs, dense suburbs, rural and wild areas. Researchers used the photos to develop a model of whether the two species are likely to be found together, and at what times.

From 347 pictures of coyotes and 943 pictures of gray foxes, they found that the two species are most likely to be found together in areas of high housing density and low forest cover -- i.e, the suburbs. Coyotes were generally less likely to live in high density housing areas than the gray fox.

"These two species were more likely to use the same sites in suburban areas, especially small forested wood lots," Parsons said. "We expected them to use these wood lots at different times to avoid each other, but actually we found that they use these suburban forest fragments at the same time."

The researchers hypothesized that they could coexist in the suburbs because coyotes are just moving through, not establishing territories, and there are still relatively few of them.

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"If they're just moving through, they may not be as prone to direct competition, or bullying of the gray foxes, or their movements are hard for the gray foxes to predict," Parsons said. "We also think gray foxes might not have a good way to avoid coyotes consistently in suburbs, since habitat is scarce, or avoidance isn't necessary given abundant suburban resources."

In rural areas, the two species were less likely to be seen together. However, gray foxes were more likely to inhabit a site as tree cover increased.

"Gray foxes are very good at climbing trees; they have sharp claws," Kays said. "They're one of the only dog relatives that can climb trees. Coyotes can't. It could be that climbing trees helps them deal with coyotes."

Researchers also saw a slight shift in the gray foxes' timing, with the gray foxes more likely to be nocturnal around coyotes.

Overall, researchers said findings for rural areas suggest gray foxes could be at risk in areas with few houses and little tree cover.

"In rural areas, where we're seeing gray foxes spatially and temporally avoid the coyotes, that's where we could see some impact on the gray fox population," Parsons said. "It could mean the coyote is outcompeting, bullying or even killing gray foxes there. A strong competitive relationship may result in gray foxes not being able to access high quality areas, forcing them to establish themselves elsewhere where resources may not be as abundant. That could be a mechanism behind a decline."

They found an important benchmark of tree cover is important for gray foxes in rural areas: Tree cover in more than 50% of a 1-kilometer radius resulted in gray foxes being more likely to occupy a site.

"Enhancing and preserving tree cover as much as we can is going to be beneficial for gray foxes," Parsons said.

Researchers said another takeaway is that humans can impact how species are able to adapt and coexist.

"There are things we can do to change the ways wildlife species are able to adapt to human-dominated environments," Parsons said. "Reducing habitat fragmentation and preserving forest and green spaces can help enhance the ability for these species to coexist."

The relationship is evolving over time, they added, and could change. Researchers are continuing to study the populations of the two species over the long term.

#Nature | https://sciencespies.com/nature/tree-cover-helps-gray-foxes-coexist-with-coyotes-in-the-country/

Ice Volcanoes Reshape Pluto and Hint at a Hidden Ocean

Signs of cryovolcanic activity on the dwarf planet in the recent geological past must be driven by an underground body of water, a study suggests.

In July 2015, NASA’s New Horizons spacecraft gave humanity its only close-up of Pluto. The spacecraft found that the dwarf planet, far from being a featureless and frigid orb, was an ostentatious world with epic impact craters, methane ice and nitrogen snow.

Two of its mountains, Wright Mons and Piccard Mons, were suspected of being volcanoes. But instead of spewing molten rock, they would be built of, and capable of erupting, ice in a process known as cryovolcanism.

After years of close examination of data from New Horizons, scientists think they have spotted evidence of recently erupted ice lava, a sign that Pluto is home to cryovolcanoes that were active in the immediate geologic past.

“We tried to find some other way to explain it, but we just really couldn’t,” said Kelsi Singer, a senior research scientist at the Southwest Research Institute in Boulder, Colo., and an author of the study, published Tuesday in the journal Nature Communications.

If the team is correct, the implications are significant. Any erupting volcano requires a molten fuel source. If these ice lava deposits are young, then the underworld just below this spot on Pluto’s icy shell was, at least to some degree, hot and liquid very recently. And such a finding gives credence to the hypothesis that present-day Pluto is an ocean world, however improbable that may seem for a tiny, icy orb so far from the sun.

In the past four decades, possible cryovolcanic features have been spotted throughout the solar system, from the dwarf planet Ceres in the asteroid belt out as far as Neptune’s wintry moon Triton.

An icy lava eruption has never been witnessed, but seeing one on a world like Pluto would be nothing short of surreal: The icy lava may slowly extrude from a dome’s vent or fissure as a gelid, mucilaginous mass — something comparable to Silly Putty but made of one or multiple frozen chemical compounds — and largely retain its chunky shape in a low-gravity, exceedingly cold environment.

The discovery of Wright Mons and Piccard Mons on Pluto, two icy mountains with central pits that looked like eruptive openings, suggested it too was a member of the cryovolcanic club. But whether these ice volcanoes were genuinely what they looked like, and whether they were still active, proved difficult to determine.

Is Pluto a Planet? What’s a Planet, Anyway?

More than 15 years after Pluto was demoted to dwarf planet, the debate, even among scientists, continues.

After their forensic examination of New Horizons’s flyby images, Dr. Singer and her colleagues suspect that Wright Mons and Piccard Mons are not two big cryovolcanoes. Instead, they are probably colonies of smaller volcanic domes, which are usually made when very gloopy lava slowly erupts and forms squat piles. It appears that many such domes grew in the same area and got squashed together, making two mountainous masses.

But is this cryovolcanic colony still alive?

The team noticed that much of the region is coated in irregular, undulating patches mostly made of water-ice. This terrain looks nothing like contorted deposits elsewhere on Pluto formed by erosion. That leaves one likely explanation: It was made by water-ice lava flows. And as their deposits lack craters, the flows erupted close to the geologic present.

Icy eruptions may be alien to this planet, but some geologic fundamentals are probably familiar: Just as Earth’s active volcanoes sit atop reservoirs of partially molten rock, Pluto’s volcanic domes may sit atop partially liquid reservoirs of water-ice. But in the dwarf planet’s case, these reservoirs may feed off one big ocean.

Earlier studies have suggested Pluto has a subsurface ocean, although explaining its existence is difficult.

A world this small would have lost the heat from its formation long ago, and it does not contain enough radioactive, heat-releasing elements in its rocky core, so any liquid below its icy outer shell should be frozen. Various heat-trapping hypotheses are also currently impossible to prove.

It’s not fanciful to imagine frozen worlds containing oceans. Europa, a moon of Jupiter, and Enceladus, which orbits Saturn, both have incontrovertible internal oceans. But the gravitational interactions with their planets and nearby moons thought to be heating them are not applicable to Pluto.

And yet Pluto’s youthful cryovolcanic terrain bolsters the case for its own subterranean seas, while adding evidence to two theories: that ocean worlds are commonplace in the cosmos, and that scientists cannot always explain how their existences are possible.

Ultimately the data from New Horizons and other spacecraft are continually teaching researchers the same lesson. “We needed to have a better imagination,” said Jani Radebaugh, a planetary scientist at Brigham Young University not involved with the study.

#News | https://sciencespies.com/news/ice-volcanoes-reshape-pluto-and-hint-at-a-hidden-ocean/

Nature-based carbon removal can help protect us from a warming planet

A new study finds that temporary nature-based carbon removal can lower global peak warming levels but only if complemented by ambitious fossil fuel emission reductions.

Nature-based climate solutions aim to preserve and enhance carbon storage in terrestrial or aquatic ecosystems and could be a potential contributor to Canada's climate change mitigation strategy. "However, the risk is that carbon stored in ecosystems could be lost back to the atmosphere as a result of wildfires, insect outbreaks, deforestation or other human activities," says Kirsten Zickfeld, a distinguished professor of climate science in Simon Fraser University's Department of Geography who is on the research team.

The researchers used a global climate model to simulate temperature change through two scenarios ranging from weak to ambitious greenhouse gas emissions reductions. In the relatively weak emissions reduction scenario, carbon emissions continue through 2100. In the ambitious scenario carbon emissions reach net-zero by 2050.

In order to meet the Paris Agreement's climate goals, the world will need to reach net-zero CO2 emissions around or before mid-century, according to the United Nations' Intergovernmental Panel on Climate Change.

In both scenarios, it is assumed that carbon storage through nature-based climate solutions is temporary as forests are vulnerable to both natural and human disturbances. Therefore, nature-based climate solutions are anticipated to withdraw carbon from the atmosphere over the next 30 years then slowly release the carbon during the second half of the century.

The team found that in a scenario with carbon emissions decreasing rapidly to net-zero, temporary nature-based carbon storage can decrease the level of peak warming. However, in a scenario with continued carbon emissions temporary nature-based carbon storage would serve only to delay the temperature increase.

"Our study shows that nature-based carbon storage, even if temporary, can have tangible climate benefits, but only if implemented alongside a rapid transition to zero fossil-fuel emissions," says Zickfeld.

The findings are published in Communications Earth & Environment.

Zickfeld is also the lead author of the recent United Nations' Intergovernmental Panel on Climate Change (IPCC) Working Group I contribution to the Sixth Assessment Report released in summer 2021, and the IPCC's 2018 special report on the global warming of 1.5 degrees.

The researchers also note that investing in protecting and restoring nature offers social and environmental benefits for local and Indigenous communities beyond storing carbon to mitigate climate change. They add that biodiversity, water and air quality are inherently valuable and that efforts to enhance these can also help to build community resilience to climate change.

Story Source:

Materials provided by Simon Fraser University. Original written by Melissa Shaw. Note: Content may be edited for style and length.

#Nature | https://sciencespies.com/nature/nature-based-carbon-removal-can-help-protect-us-from-a-warming-planet/