NASA's Hubble Space Telescope has confirmed the largest icy comet nucleus ever seen by scientists. NPR reports: The nucleus of comet C/2014 UN271 (Bernardinelli-Bernstein) is about 80 miles in diameter, which is larger than the state of Rhode Island, NASA says. The comet's nucleus is about 50 times larger than that of most comets, and its mass is estimated to be a gigantic 500 trillion tons.

Comet C/2014 UN271 was discovered by astronomers Pedro Bernardinelli and Gary Bernstein using archival images from the Cerro Tololo Inter-American Observatory in Chile. The comet has been observed since 2010, when it was 3 billion miles away from the sun, and has been studied since then. NASA says there was a challenge in measuring the comet's nucleus because it was too far away for the Hubble telescope to determine its size. Instead, scientists had to make a computer model that was adjusted to fit the images of the comet's bright light that they got from the telescope's data.

Despite traveling at 22,000 mph, the massive comet is still coming from the edge of the solar system. But NASA assures us that it will never get closer than 1 billion miles away from the sun -- and even then, that won't be until 2031. The previous record-holder for largest comet nucleus was discovered in 2002. Comet C/2002 VQ94 was approximately 60 miles across.

NASA has signed up to test SpinLaunch's extraordinary whirl 'n' hurl space launch technology, which accelerates a launch vehicle to hypersonic speeds using an electric centrifuge instead of a rocket, hurling it skyward like a space discus. New Atlas reports: The idea behind SpinLaunch is as staggering as the company's name is appropriate. The idea of winding up and throwing satellites most of the way into orbit just boggles the mind. But in initial testing, this company's kinetic launch system, which looks externally a lot like a turbocharger, has shown promise as an environmentally-friendly, and potentially cost-effective replacement for first-stage rocket launches. [T]he company says it'll be appropriate for smaller launch vehicles weighing up to about 440 lb (200 kg), carrying ultra-ruggedized satellites capable of dealing with the forces involved. The SpinLaunch system will do the first part, flinging them high into the air, where a second-stage rocket can take over and give them the final push into orbit.

And the advantages are pretty compelling. SpinLaunch says that eliminating the first-stage rocket from the launch vehicle will cut out some 70 percent of the fuel and structures needed by a traditional launch vehicle, and that it can get appropriate loads into orbit using a quarter of the fuel, and at a tenth of the price. NASA is one of many parties interested in this possibility, and it's now signed a Space Act agreement with SpinLaunch to develop and integrate a NASA payload for this kinetic launch system, which will be flung skyward from Spaceport America, New Mexico, in a test flight later this year.

This, like all SpinLaunch "regular" test flights to date, will be a slower sub-orbital launch with a speed closer to 1,000 mph (1,600 km/h, Mach 1.3) than 5,000 mph. The payload will be designed to take a range of measurements, which will be analyzed by both groups. All non-proprietary information learned from this test will be published, and SpinLaunch says it's working towards its first orbital launch in 2025. A render posted late last year by SpinLaunch shows how their system works.

An anonymous reader quotes a report from Ars Technica: Putin said Russia is working on a "next-generation transport ship," as well as a nuclear-powered space tug. And, according to Russian media reports, Putin added, "We will resume the lunar program." The next-generation ship presumably refers to the "Orel," or Eagle, spacecraft that would be capable of launching cosmonauts into low Earth orbit as well as to the Moon. The problem with this is that Orel, under various guises and names, has been in development for nearly two decades and is likely years away from flying -- if it ever does. And the nuclear-powered space tug is a concept that is years or more likely decades-to-never away from launching.

That leaves the lunar program Putin mentioned. He is referring to a series of three robotic missions planned for launch to the Moon, Luna 25, Luna 26, and Luna 27. These missions, too, have been in the planning stages for a long, long time. Luna 25 was originally scheduled to launch on a Soyuz rocket a decade ago, and its current launch date is now August 2022. There is reason to be skeptical about all of the above happening, because even before the war in Ukraine, Putin significantly slashed Roscosmos' budget. Now, more resources than ever will likely be devoted to the war effort. Hours after Putin made his announcements, the European Space Agency (ESA) Council agreed to discontinue cooperative activities with Russia on the three Luna missions. "The Russian aggression against Ukraine and the resulting sanctions put in place represent a fundamental change of circumstances and make it impossible for ESA to implement the planned lunar cooperation," the space agency said in a statement.

Instead, the council said it would now work with NASA and its commercial partners.

A SpaceX Crew Dragon safely delivered four private astronauts to the International Space Station this past Saturday. Gizmodo reports: SpaceX capsule Endeavor reached the ISS at 8:20 a.m. EDT on Saturday, April 9, following a nearly 21-hour journey. The crew of the Ax-1 mission -- Michael Lopez-Alegria, Larry Connor, Eytan Stibbe, and Mark Pathy -- launched atop a Falcon 9 rocket on Thursday from Kennedy Space Center in Florida. The ISS is currently orbiting at a height of 260 miles (418 km) above Earth. The docking would've happened 45 minutes earlier, had it not been for a problem having to do with ISS crew members not being able to receive video from the Crew Dragon's center line camera. Ground controllers remedied the problem by routing video from a SpaceX ground station, according to NASA.

The four crew members will stay on the orbital outpost for eight days, where they will perform some 25 experiments having to do with science, education, and commercial activities. Axiom Space is aiming to build the world's first fully commercial space station, the construction of which is slated to begin at the ISS in late 2024. The Ax-1 mission represents an important milestone in the ongoing commercialization of low Earth orbit. [...] Axiom said the first day was mostly about preparing equipment for what will be a very busy week. The team has just 100 hours to complete their respective tasks.

NBC News looks at the "thriving ecosystem" of space businesses "dramatically expanding access to the cosmos and fueling what is projected to grow into a trillion-dollar commercial space industry."

"Yet alongside the numerous benefits to society, increasing access to space and supporting an economy in orbit comes with its share of challenges, including how to balance a growing industry with the safe and sustainable use of outer space...." Speckled among the operational satellites in low-Earth orbit are thousands of tons of space debris, ranging from tiny flecks of paint to spent rocket parts to huge defunct spacecraft that have languished in orbital graveyards for decades. Adding more satellites to the mix not only increases the chances of a catastrophic on-orbit collision, but also pushes humanity closer to a perilous tipping point, beyond which certain parts of low-Earth orbit may become too cluttered and risky to operate in safely. "We're really on borrowed time before we have another big collision," said Charity Weeden, vice president of global space policy and government relations at Astroscale U.S., a private company that specializes in satellite servicing and orbital debris removal. "There are thousands of close calls every day in orbit...."

But placing all the blame on these megaconstellations is oversimplifying the problem, said Darren McKnight, a senior technical fellow at LeoLabs, a California-based aerospace company that operates networks of ground-based radars and tracking systems to monitor objects in low-Earth orbit and map their movements. For one, operational satellites make up only a small fraction of the total number of objects in low-Earth orbit that pose collision risks, he said. And unlike defunct spacecraft that have languished in orbit for decades, most newer satellites can be maneuvered out of harm's way, if necessary. It has also become standard practice for satellite operators to have an end-of-life plan to cut down on the accumulation of space junk. These strategies include purposefully commanding a spacecraft to "deorbit," or burn up harmlessly in Earth's atmosphere, or strand it in a higher, "graveyard" orbit away from the most congested sections around the planet.

Still, the risks are serious. And the amount of debris in space is expected to grow as launches continue. McKnight said "bad neighborhoods" have already emerged — areas in low-Earth orbit where big clouds of debris pose very real threats." There are certain places in Earth orbit where we are destined to have a major event within the next five to 10 years," he said. "We're looking at a 10 to 15 percent probability of a collision, which sounds unlikely, but by leaving these objects in orbit since the mid-'80s, we're rolling the dice a lot"

These risks were amplified by a series of recent anti-satellite missile tests — one conducted by China in 2007, one by India in 2019 and one carried out by Russia last year — and a separate accidental collision between two satellites in 2009. Each event is estimated to have produced thousands of pieces of debris larger than the size of a golf ball, and even smaller, harder-to-track objects, according to the Secure World Foundation, a nongovernmental organization that focuses on space policy...

Part of the problem is that while launches are subject to domestic regulations in individual countries, there is no international body to oversee what happens in orbit. Policies have yet to catch up with the industry's growth, and it's unclear if any binding global agreements can be achieved anytime soon.

"It's like we're building the plane as we're flying it," said Josef Koller, a systems director for the Center for Space Policy and Strategy at The Aerospace Corp.
The article also points out that companies like Astroscale are currently "developing technologies to actively remove objects from orbit."

"Weather predictions here on Earth are more accurate than they've ever been," writes ScienceAlert.

"Trying to predict the behavior of our wild and wacky Sun is a little more tricky." Case in point: according to official predictions, the current cycle of solar activity should be mild. But the gap between the prediction and what's actually happening is pretty significant — and it's getting wider. Sunspot counts, used as a measure for solar activity, are way higher than the predicted values calculated by the NOAA, NASA, and the International Space Environmental Service.

In fact, sunspot counts have been consistently higher than predicted levels since September 2020. This could mean that, in contrast to predictions, the Sun is in the swing of an unusually strong activity cycle.... [T]he number of sunspots for the last 18 months has been consistently higher than predictions. At time of writing, the Sun has 61 sunspots, and we're still over three years from solar maximum.
Here's what makes that even more significant. In 2020 a team of scientists (led by solar physicist Scott McIntosh of the U.S. National Center for Atmospheric Research) predicted that, based on long-term solar cycle trends, this solar cycle was likely to be stronger — and perhaps one of the strongest ever recorded.

They'd also said in 2020 that scientists "lacked a fundamental understanding" of the mechanism behind sun spot cycles, and argued that if this sun cycle proves them correct, "we will have evidence that our framework for understanding the Sun's internal magnetic machine is on the right path."

Thanks to long-time Slashdot reader schwit1 for sharing this article

The New York Times reports: Pristine slivers of the impactor that killed the dinosaurs have been discovered, said scientists studying a North Dakota site that is a time capsule of that calamitous day 66 million years ago... "If you're able to actually identify it, and we're on the road to doing that, then you can actually say, 'Amazing, we know what it was,'" Robert DePalma, a paleontologist spearheading the excavation of the site, said Wednesday during a talk at the NASA Goddard Space Flight Center in Greenbelt....

A New Yorker article in 2019 described the site in southwestern North Dakota, named Tanis, as a wonderland of fossils buried in the aftermath of the impact some 2,000 miles away. Many paleontologists were intrigued but uncertain about the scope of DePalma's claims; a research paper published that year by DePalma and his collaborators mostly described the geological setting of the site, which once lay along the banks of a river. When the object hit Earth, carving a crater about 100 miles wide and nearly 20 miles deep, molten rock splashed into the air and cooled into spherules of glass, one of the distinct calling cards of meteor impacts. In the 2019 paper, DePalma and his colleagues described how spherules raining down from the sky clogged the gills of paddlefish and sturgeon, suffocating them.

Usually the outsides of impact spherules have been mineralogically transformed by millions of years of chemical reactions with water. But at Tanis, some of them landed in tree resin, which provided a protective enclosure of amber, keeping them almost as pristine as the day they formed.... Finding amber-encased spherules, he said, was the equivalent of sending someone back in time to the day of the impact, "collecting a sample, bottling it up and preserving it for scientists right now...."

DePalma said there also appear to be some bubbles within some of the spherules. Because the spherules do not look to be cracked, it's possible that they could hold bits of air from 66 million years ago.
In 1998, UCLA geochemist Frank Kyte claimed he'd found a fragment of that meteor in a core sample drilled off Hawaii, the article points out, "but other scientists were skeptical that any bits of the meteor could have survived."

But now DePalma tells the Times that this North Dakota discovery "actually falls in line with what Frank Kyte was telling us years ago."

Nissan is working with NASA on a new type of battery for electric vehicles that promises to charge more quickly and be lighter yet safe, the Japanese automaker said Friday. CBS News reports: The all-solid-state battery will replace the lithium-ion battery now in use for a 2028 product launch and a pilot plant launch in 2024, according to Nissan. The battery would be stable enough to be used in pacemakers, Nissan said. When finished, it will be about half the size of the current battery and fully charge in 15 minutes instead of a few hours.

The collaboration with the U.S. space program, as well as the University of California San Diego, involves the testing of various materials, Corporate Vice President Kazuhiro Doi told reporters. "Both NASA and Nissan need the same kind of battery," he said. Nissan and NASA are using what's called the "original material informatics platform," a computerized database, to test various combinations to see what works best among hundreds of thousands of materials, Doi said. The goal is to avoid the use of expensive materials like rare metals needed for lithium-ion batteries.

Loren Grush writes via The Verge: Tomorrow morning, SpaceX is set to launch yet another crew of four to the International Space Station from Florida -- but unlike most of the company's passenger flights, this new crop of flyers won't include any current NASA astronauts. All four members of the crew are civilians, flying with a commercial aerospace company called Axiom Space. Their flight will mark the first time a completely private crew has visited the ISS. It's a new type of human spaceflight mission and one that comes with a hefty price tag for its participants. Three of the four flyers have each paid a reported $55 million for their seats on SpaceX's crew capsule, called the Crew Dragon. The trio of novice spacefarers includes Canadian investor Mark Pathy, American real estate investor Larry Connor, and former Israeli Air Force pilot Eytan Stibbe. The commander of the trip is a spaceflight veteran: Michael Lopez-Alegria, a former NASA astronaut who has flown four missions to space and now serves as a vice president of Axiom.

Their mission, called Ax-1, is the latest in an emerging trend of completely private astronaut flights to orbit. [...] Axiom -- which strives to create a fleet of commercial space stations -- has arranged for three additional private crew missions to the ISS, just like Ax-1, to gear up for the creation of its first station. The company's goal is to "make space more accessible to everyone." "This really does represent the first step where a bunch of individuals who want to do something meaningful in low Earth orbit -- that aren't members of a government -- are able to take this opportunity," Mike Suffredini, Axiom's CEO and the former program manager of the ISS at NASA, said during a press conference. Though, until costs come down, such individuals will need a fat wallet.

An anonymous reader quotes a report from Motherboard: An object from another star system crashed into Earth in 2014, the United States Space Command (USSC) confirmed in a newly-released memo. The meteor ignited in a fireball in the skies near Papua New Guinea, the memo states, and scientists believe it possibly sprinkled interstellar debris into the South Pacific Ocean. The confirmation backs up the breakthrough discovery of the first interstellar meteor -- and, retroactively, the first known interstellar object of any kind to reach our solar system -- which was initially flagged by a pair of Harvard University researchers in a study posted on the preprint server arXiv in 2019.

Amir Siraj, a student pursuing astrophysics at Harvard who led the research, said the study has been awaiting peer review and publication for years, but has been hamstrung by the odd circumstances that arose from the sheer novelty of the find and roadblocks put up by the involvement of information classified by the U.S. government. The discovery of the meteor, which measured just a few feet wide, follows recent detections of two other interstellar objects in our solar system, known as 'Oumuamua and Comet Borisov, that were much larger and did not come into close contact with Earth.

"I get a kick out of just thinking about the fact that we have interstellar material that was delivered to Earth, and we know where it is," said Siraj, who is Director of Interstellar Object Studies at Harvard's Galileo Project, in a call. "One thing that I'm going to be checking -- and I'm already talking to people about -- is whether it is possible to search the ocean floor off the coast of Papua New Guinea and see if we can get any fragments." Siraj acknowledged that the odds of such a find are low, because any remnants of the exploded fireball probably landed in tiny amounts across a disparate region of the ocean, making it tricky to track them down. "It would be a big undertaking, but we're going to look at it in extreme depth because the possibility of getting the first piece of interstellar material is exciting enough to check this very thoroughly and talk to all the world experts on ocean expeditions to recover meteorites," he noted. "Siraj called the multi-year process a 'whole saga' as they navigated a bureaucratic labyrinth that wound its way though Los Alamos National Laboratory, NASA, and other governmental arms, before ultimately landing at the desk of Joel Mozer, Chief Scientist of Space Operations Command at the U.S. Space Force service component of USSC," adds Motherboard.

Mozer confirmed that the object indicated "an interstellar trajectory," which was first brought to Siraj's attention last week via a tweet from a NASA scientist. He's now "renewing the effort to get the original discovery published so that the scientific community can follow-up with more targeted research into the implications of the find," the report says.

Slashdot reader alaskana98 writes: In what has become a stubborn sibling to the 'Face on Mars' phenomenon, the legend of the Dark Knight alien satellite has persisted for years and is the fascinating story of a seemingly mundane NASA photo tied together with reports of seemingly mysterious radio waves captured in the early days of radio, all combining to make the ultimate space conspiracy theory.

It goes something like this — an ancient alien space probe, dubbed the 'Dark Knight, has been long orbiting Earth and covertly monitoring its blissfully unaware inhabitants for mysterious purposes for roughly 10,000 years. Flash forward to the 1899, where technological pioneer Nikola Tesla, while experimenting with radio technology in his Colorado laboratory supposedly captured mysterious emanations from an unearthly object. Later in the 1920's, Norwegian engineer Jørgen Hals found that radio signals he transmitted were being echoed back to him a few seconds later, something called 'long delayed echoes' — still unexplained to this day. It has been proposed that these echoes were signals being relayed back to earth by something called a 'Bracewell Probe', a hypothetical automated spacecraft sent out with the goal of making contact with other intelligent species.

Flash forward to 1998, an unassuming photo from the STS-88 mission in 1998 to attach the U.S. module to the Russian portion of the ISS captured a tantalizing glimpse of an unnaturally geometric shape menacingly loitering toward the bottom of the frame. To true believers, this was evidence of an ancient probe keeping tabs on the earthly locals. Combined, these disparate events swirl together to create the stuff of dreams for the ardent conspiracy theorist and even the causal sci-fi buff. Ultimately, the object in the STS photo was most likely a thermal cover. The radio waves Tesla heard? Likely natural radio emisions of a natural or terestial source.

Space.com took a deep dive into this myth and explored how it — and the - dark knight myth has taken a hold on the imaginations of those who find themselves peering out into the inky blackness of the night and wonder to themselves "are we being watched from above"?

The Paramount+ streaming service already has five ongoing Star Trek series (including Discovery and Picard).

But they've just released a trailer for another one — and it's now derived directly from the original 1960s TV show, even including some of its original characters. The upcoming show's title?

Star Trek: Strange New Worlds.

Ars Technica reports: As we've reported previously, one of the highlights of Star Trek: Discovery's second season was the appearance of classic original series (TOS) characters Capt. Christopher Pike (Anson Mount), Number One (Rebecca Romijn), and Spock (Ethan Peck). All three reprise their roles for Strange New Worlds....

"If you want to seek out new life, go where the aliens are," Pike tells us. But that alien life might not be receptive to first contact, as Pike and the Enterprise find themselves under fire by aliens who consider their presence to be "blasphemy." And romance blooms for both Pike and Spock (separately, not with each other).

Star Trek: Strange New Worlds debuts on Paramount+ on May 5, 2022. The streaming platform has already greenlighted a second season, with Paul Wesley (Vampire Diaries ) joining the cast as future Enterprise Capt. James T. Kirk.
Ars Technica reports the cast as:

• Babs Olusanmokun playing Dr. M'Benga
• Celia Rose Gooding filling Nichelle Nichols' shoes as Cadet Nyota Uhura
• Jess Bush playing Nurse Christine Chapel
• Melissa Navai playing Lt. Erica Ortegas
• Bruce Orak playing an Aenar named Hemmer.
• Christina Chong playing La'An Noonien-Singh (a relation of the classic revenge-obsessed Star Trek villain Khan).

And on an unrelated note...

"For 50 years, interplanetary probes have returned thousands of striking images of the surface of Mars, but never a single sound." So says the largest fundamental science agency in Europe, the French National Centre for Scientific Research (France's state research organisation).

Then they made a surprising discovery, reports CBS News: Researchers studying recordings made by microphones on NASA's Perseverance rover found that sound travels much slower on Mars than it does on Earth... In addition, the researchers realized that there are two speeds of sound on Mars — one for high-pitched sounds and one for low-pitched sounds. This would "make it difficult for two people standing only five meters apart to have a conversation," according to a press release on the findings.

The unique sound environment is due to the incredibly low atmospheric surface pressure. Mars' pressure is 170 times lower than Earth's pressure. For example, if a high-pitched sound travels 213 feet on Earth, it will travel just 26 feet on Mars.

While sounds on Mars can be heard by human ears, they are incredibly soft. "At some point, we thought the microphone was broken, it was so quiet," said Sylvestre Maurice, an astrophysicist at the University of Toulouse in France and lead author of the study, according to NASA. Besides the wind, "natural sound sources are rare," the press release said.

But NASA scientists think Mars may become more noisy in the autumn months, when there is higher atmospheric pressure. "We are entering a high-pressure season," co-author of the study Baptiste Chide said in the press release. "Maybe the acoustic environment on Mars will be less quiet than it was when we landed."

"Russia's Roscosmos will stop working with NASA and other western space agencies on the International Space Station," reports Engadget: On early Saturday morning, Roscosmos director Dmitry Rogozin slammed international sanctions against Russia and said normal cooperation between the space agency and its western counterparts would only be possible after they were lifted.... Rogozin said Roscosmos would submit proposals on ending its work with NASA and other international space agencies to Russian authorities.

It's unclear how the decision would affect the space station. The ISS is not owned by any single country. The US, European Union, Russia, Canada and Japan operate the station through a cooperative agreement between the countries. Roscosmos, however, is critical to the ISS. The Russian Orbital Segment handles guidance control for the entire station....

The ISS isn't the first joint space program to see its future thrown into uncertainty due to rising tensions between the West and Russia. In March, Roscosmos said it would not ferry OneWeb's internet satellites to space until the UK government sold its stake in the company. That same month, the European Space Agency announced it was suspending its joint ExoMars mission with Roscosmos.
But in the middle of all this, "There are currently seven astronauts onboard the ISS — three Russian cosmonauts, three NASA astronauts and one German-born ESA astronaut, Matthias Maurer..." reports UPI: The three Russian cosmonauts are Sergey Korsakov, Oleg Artemyev and Denis Matveev. It was not immediately clear how the suspension of cooperation would impact the cosmonauts at the ISS.

Artemyev has expressed support for Russia and its decision to invade Ukraine in a statement made last month after he boarded the space station in a yellow and blue uniform, the colors of the Ukrainian flag. "There is no need to look for secret signs and symbols in our uniform. Color is just color," he said. "Despite the fact that we are in space, we are together with our president and people!"

Despite the United States and Russia's deteriorating relationship here on Earth, Russia is still considering extending its participation on the International Space Station through 2030, according to NASA. However, it could be a few months before there is a solid update on Russia's official stance. From a report: NASA and Russia's state space corporation, Roscosmos, have been the two largest partners on the International Space Station for the last three decades. The two organizations have agreed to work together on the ISS through 2024, but at the end of last year, the Biden administration announced its intentions to extend the space station program through 2030. Russia has not formally agreed to the extension yet.

Roscosmos's participation in the extension started to seem unlikely after Russia invaded Ukraine in February. In response to the war, the United States sanctioned Russia's major industries, which triggered outrage from the head of Roscosmos, Dmitry Rogozin. On Twitter, Rogozin made wild threats about the future of the ISS, insinuating that the station could come crashing down on the United States if Russia withdrew prematurely from the program. He has also hinted at revisiting the partnership with the US in light of the sanctions.

"Following up on a 2020 submission, more samples and hi-res data have been added to NASA's research-grade Astromaterials 3D site," writes Slashdot reader White Yeti. "I don't see a new/news link, so here's text from the informal release statement." From the release: Astromaterials 3D, the first virtual library of NASA's collections of Apollo Lunar and Antarctic Meteorite samples, is releasing 20 new lunar and meteorite samples to the public this month! This launch also includes the release of an exciting new feature, called NASA Pins, which allows the public to view pre-selected sample characteristics on each rock's surface and within the XCT imagery, in order to share the incredible science these space rocks reveal. Each NASA Pin is curated by NASA Scientists and includes brief explanations about each pinned feature. This launch also includes the highly anticipated public release of the actual high-resolution OBJ files that the Astromaterials 3D team creates for each rock, easily and freely downloadable from every rock's page. Originally launched to the public in December 2020, the Astromaterials 3D Website and Explorer Application continues to grow, offering a dynamic, interactive, and information-rich visualization tool for researchers and the general public. Keep your eye on the site for this exciting forthcoming release: https://ares.jsc.nasa.gov/astromaterials3d/.

A Nasa astronaut caught a Russian ride back to Earth on Wednesday after a US record 355 days at the International Space Station, returning with two cosmonauts to a world torn apart by war. From a report: Mark Vande Hei landed in a Soyuz capsule in Kazakhstan alongside the Russian Space Agency's Anton Shkaplerov and Pyotr Dubrov, who also spent the past year in space. Despite escalating tensions between the US and Russia over Vladimir Putin's war with Ukraine, Vande Hei's return followed customary procedures. A small Nasa team of doctors and other staff was on hand for the touchdown and planned to return immediately to Houston with the 55-year-old astronaut.

Even before Russia's invasion of Ukraine, Vande Hei said he was avoiding the subject with his two Russian crewmates. Despite getting along "fantastically ... I'm not sure we really want to go there," he said. It was the first taste of gravity for Vande Hei and Dubrov since their Soyuz launch on 9 April last year. Shkaplerov joined them at the orbiting lab in October, escorting a Russian film crew up for a brief stay. To accommodate that visit, Vande Hei and Dubrov doubled the length of their stay. Before departing the space station, Shkaplerov embraced his fellow astronauts as "my space brothers and space sister."

InfiniteZero shares a report from Space.com: Last Wednesday (March 23), NASA astronaut Raja Chari and the European Space Agency's Matthias Maurer spent nearly seven hours outside the International Space Station, performing a variety of maintenance work. Amazingly, astrophotographer Sebastian Voltmer managed to capture a snapshot of the spacewalk action from the ground -- and from Maurer's hometown of Sankt Wendel, Germany, no less. "I feel like I just made a once-in-a-lifetime image," Voltmer wrote at SpaceWeather.com, which featured the photo in its online gallery.

Existence of volcanoes makes idea that dwarf planet is inert ball of ice look increasingly improbable. From a report: Strung out in the icy reaches of our solar system, two peaks that tower over the surface of the dwarf planet Pluto have perplexed planetary scientists for years. Some speculated it could be an ice volcano, spewing out not lava but vast quantities of icy slush -- yet no cauldron-like caldera could be seen. Now a full analysis of images and topographical data suggests it is not one ice volcano but a merger of many -- some up to 7,000 metres tall and about 10-150km across. Their discovery has reignited another debate: what could be keeping Pluto warm enough to support volcanic activity? Sitting at the southern edge of a vast heart-shaped ice sheet, these unusual surface features were initially spotted when Nasa's New Horizons spacecraft flew past in July 2015, providing the first close-up images of the icy former planet and its moons.

"We were instantly intrigued by this area because it was so different and striking-looking," said Dr Kelsi Singer, a New Horizons co-investigator and deputy project scientist at Southwest Research Institute in Boulder, Colorado. "There are these giant broad mounds, and then this hummocky-like, undulating texture superimposed on top; and even on top of that there's a smaller bouldery kind of texture." At the time, an ice volcano seemed like the least-weird explanation for these features -- there were no impact craters from asteroids or meteors nearby, suggesting these features had been erased by relatively recent geological events; and no evidence of plate tectonics -- a key contributor to mountain formation on Earth.

SpaceX has ended production of new Crew Dragon astronaut capsules, a company executive told Reuters, as Elon Musk's space transportation company heaps resources on its next-generation spaceship program. From the report: Capping the fleet at four Crew Dragons adds more urgency to the development of the astronaut capsule's eventual successor, Starship, SpaceX's moon and Mars rocket. Starship's debut launch has been delayed for months by engine development hurdles and regulatory reviews. It also poses new challenges as the company learns how to maintain a fleet and quickly fix unexpected problems without holding up a busy schedule of astronaut missions.

"We are finishing our final (capsule), but we still are manufacturing components, because we'll be refurbishing," SpaceX President Gwynne Shotwell told Reuters, confirming the plan to end Crew Dragon manufacturing. She added that SpaceX would retain the capability to build more capsules if a need arises in the future, but contended that "fleet management is key." Musk's business model is underpinned by reusable spacecraft, so it was inevitable the company would cease production at some point. But the timing was not known, nor was his strategy of using the existing fleet for its full backlog of missions. "Crew Dragon has flown five crews of government and private astronauts to space since 2020, when it flew its first pair of NASA astronauts and became the U.S. space agency's primary ride for getting humans to and from the International Space Station," notes Reuters.