Three Chinese astronauts, also known as taikonauts, safely returned to Earth yesterday after spending six months aboard China's unfinished Tiangong space station, according to a report from Space.com. This is China's second crewed mission to Tiangong and its longest so far. From a report: The Shenzhou 13 spacecraft landed in the Inner Mongolia desert at 9:56AM local time on Saturday morning after departing from the space station's core Tianhe module about nine hours prior. The crew took off from the Jiuquan Satellite Launch Center in the Gobi desert last October and spent a total of 183 days on the space station. This mission is China's longest.

In addition, taikonaut Wang Yaping made history as the first Chinese woman to visit the Tianhe space station and also became the first Chinese woman to conduct a spacewalk. Wang was accompanied by crewmate Ye Guangfu and commander Zhai Zhigang. The trio carried out a total of two spacewalks, performed various tests around the station, and held two live lectures for students watching from Earth. Shenzhou 13 is part of 11 missions China has planned to finish constructing the Tiangong space station. China first launched the Tianhe module in April 2021 and later sent three taikonauts to bring the station online. As noted by Space.com, the Shenzhou 14 crew is set to depart for the space station sometime in June. China plans on having the station finished by the end of the year, which will include the launch of two additional modules.

"Astronomers have discovered a dusty, red object 13 billion light-years from Earth that may be the earliest known ancestor of a supermassive black hole," reports Live Science: The ancient object shows characteristics that fall between dusty, star-forming galaxies and brightly glowing black holes known as quasars, according to the authors of a new study, published April 13 in the journal Nature. Born just 750 million years after the Big Bang, during an epoch called the "cosmic dawn," the object appears to be the first direct evidence of an early galaxy weaving stardust into the foundations of a supermassive black hole.

Objects like these, known as transitioning red quasars, have been theorized to exist in the early universe, but they have never been observed — until now....

Prior research has shown that quasars existed within the first 700 million years of the universe, the study authors wrote; however, it's unclear exactly how these supermassive objects formed so quickly after the Big Bang. Simulations suggest that some sort of fast-growing transition phase occurs in dusty, star-dense galaxies. "Theorists have predicted that these black holes undergo an early phase of rapid growth: a dust-reddened compact object emerges from a heavily dust-obscured starburst galaxy," study co-author Gabriel Brammer, an associate professor at the Niels Bohr Institute, said in the statement. In their new paper, the researchers claim to have detected one of these rare transitional objects — officially named GNz7q — while studying an ancient, star-forming galaxy with the Hubble Space Telescope.

The team caught the early galaxy in the midst of a stellar baby boom, with the galaxy seemingly churning out new stars 1,600 times faster than the Milky Way does today. All those newborn stars produced an immense amount of heat, which warmed the galaxy's ambient gas and caused it to glow brightly in infrared wavelengths. The galaxy became so hot, in fact, that its dust shines brighter than any other known object from the cosmic dawn period, the researchers said. Amid that brightly glowing dust, the researchers detected a single red point of light — a large, compact object tinged by the enormous fog of dust around it. According to the researchers, this red dot's luminosity and color perfectly match the predicted characteristics of a transitioning red quasar....

[T]here are likely many, many others like it just waiting to be discovered by telescopes that can peer even further back, into the earliest eras of the universe. NASA's James Webb Space Telescope, which launched on Dec. 25, 2021, will be able to hunt for these elusive objects with much greater clarity than Hubble, the researchers wrote, hopefully shedding a bit more light onto the dusty cosmic dawn.

"It was one of the most eagerly awaited scientific announcements of all time, and it pitted the world of faith against the world of rational thought, under the glare of the media," remembers the Guardian. So when cutting-edge carbon-14 tests found that the Shroud of Turin was a forgery, it seemed like the final chapter for a relic that had been revered for centuries as the cloth in which Christ's body had been wrapped when he supposedly rose from the dead at the first Easter almost 2,000 years ago.

But one man — David Rolfe, a film-maker whose documentary The Silent Witness had brought the shroud into the public eye in modern times, and who had converted to Christianity as a result of his research — wasn't prepared to give up on it. He was convinced the carbon dating, carried out in 1988 under the direction of the British Museum and Oxford University, had been flawed. And now he claims he has the evidence to prove it. This week sees the release of a new film, Who Can He Be?, in which Rolfe argues that, far from the shroud being a definite dud, new discoveries in the past few years have again opened the question of its authenticity. So convinced is Rolfe that he's issuing a challenge worth $1m to the British Museum. "If ... they believe the shroud is a medieval forgery, I call on them to repeat the exercise, and create something similar today," he says....

The sample used for the tests, Rolfe argues in his new film, was too small and taken from a corner where the shroud was likely to have been repaired over the centuries....

When it comes to the carbon dating, he's certainly not alone in his scepticism. Barrie M Schwortz, a photographer who documented the shroud in 1978, says "murky" would be a good word to describe the events of 1988. "Today there are at least six peer-reviewed scientific articles that challenge the results of the carbon dating," he says. In his view, the players involved were in a hurry to get the job done, because they wanted to get carbon dating on the map. "Those tests made it a household name, and today it's used widely in archaeology," he says....

The British Museum is less willing to get involved this time around. "Any current questions about the shroud would be best put to those who currently care for it in the royal chapel of the cathedral of Turin," a spokesperson said.

"After three attempts to complete a critical fueling test of the Space Launch System rocket, NASA has decided to take a break," reports Ars Technica: On Saturday night the space agency announced plans to roll the large SLS rocket from the launch pad at Kennedy Space Center to the Vehicle Assembly Building in the coming days. This marks a notable step back for the program, which has tried since April 1 to complete a "wet dress rehearsal" test, during which the rocket is fueled and brought to within 10 seconds of launch. The decision comes after three tries during the last two weeks. Each fueling attempt was scuttled by one or more technical issues with the rocket, its mobile launch tower, or ground systems that supply propellants and gases. During the most recent attempt, on Thursday April 14, NASA succeeded in loading 49 percent of the core-stage liquid oxygen fuel tank and 5 percent of the liquid hydrogen tank. [NASA reports that the team ended the test after "observing a liquid hydrogen leak on the tail service mast umbilical."]

While this represents progress, it did not include the most dynamic portion of the test, during which the rocket is fully fueled and pressurized; and it, the ground systems, and computer systems are put into a terminal countdown when every variable is closely monitored. NASA had hoped to complete this wet dress rehearsal test to work out the kinks in the complicated launch system so that, when the rocket is rolled out later this year for its actual launch, the countdown will proceed fairly smoothly. NASA said that its contractors, as well as its agency's, will use the next several weeks to address problems that cropped up during the fueling tests when the SLS rocket returns to the large Vehicle Assembly Building. For example, gaseous nitrogen system supplier Air Liquide will upgrade its capabilities. NASA will also replace a faulty check valve on the upper stage of the rocket, as well as fix a leak on the mobile launch tower's "tail service mast umbilical," a 10-meter-tall structure that provides propellant and electricity lines to the rocket on the pad....

Still, NASA seems confident that it will get through this painful teething process for the SLS rocket: a program that is now 11 years old and in which NASA has invested more than $30 billion in the rocket and ground systems now being tested. "There's no doubt in my mind that we will finish this test campaign, and we will listen to the hardware, and the data will lead us to the next step," Blackwell-Thompson said Friday. "And we will take the appropriate steps, and we will launch this vehicle. I don't know exactly what that date is, but there's no doubt in my mind that we'll finish the test campaign, and we will be ready to go fly."

"The U.S. Space Command announced this week that it determined a 2014 meteor hit that hit Earth was from outside the solar system," reports CBS News. "The meteor streaked across the sky off the coast of Manus Island, Papua New Guinea three years earlier than what was believed to be the first confirmed interstellar object detected entering our solar system."

After Oumuamua was spotted in 2017, the interstellar comet Borisov appeared in 2019 — discovered in Crimea, Ukraine at a "personal observatory" built by amateur astronomer Gennadiy Borisov"

But CBS notes that despite their theory about a first interstellar meteor in 2014, the two Harvard astronomers — Dr. Amir Siraj and Dr. Abraham Loeb — "had trouble getting their paper published, because they used classified information from the government." Specifically, data from a classified U.S. government satellite designed to detect foreign missiles... The meteor was unusual because of its very high speed and unusual direction — which suggested it came from interstellar space.... Any space object traveling more than about 42 kilometers per second may come from interstellar space. The data showed the 2014 Manus Island fireball hit the Earth's atmosphere at about 45 kilometers per second, which was "very promising" in identifying it as interstellar, Siraj said....

After more research and help from other scientists, including classified information from the government about the accuracy or level of precision of the data, Siraj and Loeb determined with 99.999% certainty the object was interstellar. But their paper on the finding was being turned down, because the pair only had a private conversation with an anonymous U.S. government employee to confirm the accuracy of the data.
"We had thought this was a lost cause," Dr. Siraj told the New York Times — which couldn't resist adding that "it turned out, the truth was out there." Last month, the U.S. Space Command released a memo to NASA scientists that stated the data from the missile warning satellites' sensors "was sufficiently accurate to indicate an interstellar trajectory" for the meteor. The publication of the memo was the culmination of a three-year effort by Siraj and a well-known Harvard astronomer, Avi Loeb.

Many scientists, including those at NASA, say that the military still has not released enough data to confirm the interstellar origins of the space rock, and a spokesperson said Space Command would defer to other authorities on the question.

But it wasn't the only information about meteors to be released. The military also handed NASA decades of secret military data on the brightness of hundreds of other fireballs, or bolides. "It's an unusual degree of visibility of a set of data coming from that world," said Matt Daniels, assistant director for space security at the White House's Office of Science and Technology Policy, who worked on the data release. "We're in this renewed period of excitement and activity in space programs generally, and in the midst of that, I think thoughtful leaders in multiple places said, 'you know, now is a good time to do this.'"
The Times notes that data from classified military satellites "could also aid NASA in its federally assigned role as defender of planet Earth from killer asteroids. And that is the goal of a new agreement with the U.S. Space Force that aims to help NASA's Planetary Defense Coordination Office better understand what happens when space rocks reach the atmosphere." Sharing sensitive military satellite data with astronomers has led to significant scientific discoveries in the past.

A group of satellites deployed in the 1960s by the United States to detect covert detonations of nuclear weapons on Earth accidentally became the key instruments used to make the first detection of extraterrestrial gamma ray bursts. The bursts showed up on the satellites, code-named Vela, as single bursts of energy, confusing analysts at Los Alamos who later declassified the data in a 1973 paper that spurred academic debate about the bursts' origins....

A core reason for Space Force's increasing ties with NASA has centered on the agency's congressional mandate to detect nearly all asteroids that could threaten the Earth. When NASA signed an agreement in 2020 to strengthen ties with Space Force, the agency acknowledged it had fallen behind in its asteroid-tracking efforts and would need Pentagon resources to carry out its planetary defense mission.

The Covid-19 pandemic "would look very different if scientists had been able to develop a treatment sooner," writes Bill Gates, in a guest essay Friday in the New York Times. This ultimately would've reduced fatalities — "and it may have been harder for myths and misinformation to spread the way they did."

But note that Gates said "treatment" — not vaccine. Gates believes most people in the public health community had expected an effective treatment would appear before vaccines became available. Unfortunately, that's not what happened. Safe, effective Covid vaccines were available within a year — a historic feat — but treatments that could keep large numbers of people out of the hospital were surprisingly slow out of the gate....

In late 2021, a few of their efforts paid off — not as soon as would have been ideal, but still in time to have a big impact. Merck and its partners developed an antiviral called molnupiravir, which was shown to significantly reduce the risk of hospitalization or death for people at high risk. Soon after, another oral antiviral, Paxlovid, made by Pfizer, also proved to be very effective, reducing the risk of severe illness or death by nearly 90 percent among high-risk, unvaccinated adults. These drugs are useful tools for combating the pandemic, but they arrived much later than they should have and, for many, they are still difficult to access....

It's a mistake to think of vaccines as the star of the show and therapeutics as the opening act you would just as soon skip. We're lucky that scientists made Covid vaccines as quickly as they did — if they hadn't, the death toll would be far worse. But in the event of another pandemic, even if the world is able to develop a vaccine for a new pathogen in 100 days, it will still take a long time to get the vaccine to most of the population.... With good therapeutics, the risk of severe illness and death could drop significantly, and countries could decide to loosen restrictions on schools and businesses, reducing the disruption to education and the economy. What's more, imagine how people's lives would change if we're able to take the next step by linking testing and treatment. Anyone with early symptoms that might indicate Covid (or any other viral disease) could walk into a pharmacy or clinic anywhere in the world, get tested and, if positive for the virus, walk out with antivirals to take at home....

In short, although therapeutics didn't rescue us from Covid, they hold a lot of promise for saving lives and preventing future outbreaks from crippling health systems. But to make the most of that promise, the world needs to invest in the research and systems we'll need to find treatments much faster. That's why my foundation has supported a therapeutics accelerator at Duke University, but broader initiatives will be necessary to make lasting change. This will require substantial investment to bring together academia, industry and the latest software tools. But if we succeed, the next time the world faces an outbreak, we'll save millions more lives.
Gates offers several specific recommendations — including "investing in large libraries of drug compounds that researchers can quickly scan to see whether existing therapies work against new pathogens." And... With advances in artificial intelligence and machine learning, it's now possible to use computers to identify weak spots on pathogens that we already know about, and we'll be able to do the same when new pathogens arise. These technologies are also speeding up the search for new compounds that will attack those weak spots. With adequate funding, various groups could take the most promising new compounds through Phase 1 studies even before there's an epidemic, or at least have several leads that can be turned into a product quickly once we know what the target looks like.

Sometimes making a brand-new type of box requires outside-the-box thinking, which is exactly what Spartan chemists used to create an eight-atom, magnetic cube. Phys.Org reports: Part of what made the researchers' idea so wild was their choice to work with starting ingredients that are notoriously finicky in the chemistry community. One ingredient is a group of elements referred to as lanthanides, which occupy a special row toward the bottom of the periodic table of elements. The other is the metallic element bismuth, which doesn't typically get too much attention (although some may recognize it from its role in bright pink antacids such as Pepto Bismol).

By finding a way to combine the bismuth with a lanthanide element -- notably terbium or dysprosium -- they created a molecule with permanent magnetic features. It's the same magnetism found in bar magnets and hard disk drives, but at a much smaller scale. The small scale of molecular magnets offers technological opportunities, such as improving the storage capacity of magnetic hard drives. There are also emerging applications where conventional magnets may simply be too large to contribute, such as in processors for quantum computers.

The first single-molecule magnet was discovered about 30 years ago and, since then, researchers have been seeking new varieties with different physical and chemical attributes. They've also been working to develop more creative chemical approaches to make the magnets. The molecule itself, though, looks simple, belying the complexity of the process required to make it. The top and bottom of the molecule are capped with rings of carbon and hydrogen atoms. Each ring is linked to a lanthanide that forms a cube with the bismuth atoms. The researchers published their findings in the journal Chem.

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 the BBC: Researchers have rejuvenated a 53-year-old woman's skin cells so they are the equivalent of a 23-year-old's. [...] The scientists in Cambridge believe that they can do the same thing with other tissues in the body. The head of the team, Prof Wolf Reik, of the Babraham Institute in Cambridge, told BBC News that he hoped that the technique could eventually be used to keep people healthier for longer as they grow older. [...] Prof Reich stressed though that the work, which has been published in the journal eLife, was at a very early stage. He said that there were several scientific issues to overcome before it could move out of his lab and into the clinic. But he said that demonstrating for the first time that cell rejuvenation is possible was a critical step forward.

Prof Reik's team used [a method, called iPS, that involves adding chemicals to adult cells to turn them into stem cells] on 53-year-old skin cells. But they cut short the chemical bath from 50 days to around 12. Dr Dilgeet Gill was astonished to find that the cells had not turned into embryonic stem cells -- but had rejuvenated into skin cells that looked and behaved as if they came from a 23-year old. He said: "I remember the day I got the results back and I didn't quite believe that some of the cells were 30 years younger than they were supposed to be. It was a very exciting day!"

The technique cannot immediately be translated to the clinic because the iPS method increases the risk of cancers. But Prof Reik was confident that now it was known that it is possible to rejuvenate cells, his team could find an alternative, safer method. "The long-term aim is to extend the human health span, rather than the lifespan, so that people can get older in a healthier way," he said. Prof Reik says some of the first applications could be to develop medicines to rejuvenate skin in older people in parts of the body where they have been cut or burned -- as a way to speed up healing. The researchers have demonstrated that this is possible in principle by showing that their rejuvenated skin cells move more quickly in experiments simulating a wound. The next step is to see if the technology will work on other tissues such as muscle, liver and blood cells.

A new immunotherapy that targets cells infected with Epstein-Barr Virus (EBV) has halted the progression of multiple sclerosis (MS) in a small trial. Perhaps even more incredibly, in some patients, it is possible that symptoms of MS were actually reversed, though this was not fully identified in the most recent presentation of results (PDF). IFLScience reports: [S]ignificant evidence has linked infection of EBV and the eventual development of MS. [...] Attempting to "transform treatment of Multiple Sclerosis," Atara Biotherapeutics has developed an allogeneic T-cell therapy called ATA188. The concept is simple -- when cells are infected with EBV, they express small proteins called antigens on the cell surface, and the immunotherapy contains immune cells that target and destroy them.

In a trial of 24 patients who received the therapy, 20 saw improvements or stability in their symptoms and no fatal or serious adverse effects were reported. Early brain scans suggest that some damaged nerve cells may have been "repaired" by the therapy in a process called remyelination, which could mean a reversal of damage caused by MS in the nervous system, but this has not yet been confirmed. While the results are extremely promising, it is an early Phase 1 trial with a small sample size and no placebo or control group, so it is unclear whether the results are significant at this stage. However, it is unlikely that this repair would occur naturally, suggesting the therapy is having a beneficial effect on some level.

An anonymous reader quotes a report from MIT News: Engineers at MIT and the National Renewable Energy Laboratory (NREL) have designed a heat engine with no moving parts. Their new demonstrations show that it converts heat to electricity with over 40 percent efficiency -- a performance better than that of traditional steam turbines. The heat engine is a thermophotovoltaic (TPV) cell, similar to a solar panel's photovoltaic cells, that passively captures high-energy photons from a white-hot heat source and converts them into electricity. The team's design can generate electricity from a heat source of between 1,900 to 2,400 degrees Celsius, or up to about 4,300 degrees Fahrenheit.

The researchers plan to incorporate the TPV cell into a grid-scale thermal battery. The system would absorb excess energy from renewable sources such as the sun and store that energy in heavily insulated banks of hot graphite. When the energy is needed, such as on overcast days, TPV cells would convert the heat into electricity, and dispatch the energy to a power grid. With the new TPV cell, the team has now successfully demonstrated the main parts of the system in separate, small-scale experiments. They are working to integrate the parts to demonstrate a fully operational system. From there, they hope to scale up the system to replace fossil-fuel-driven power plants and enable a fully decarbonized power grid, supplied entirely by renewable energy. The researchers published their findings in the journal Nature.

Summer on Neptune seems to be cooling down. Observations dating back to 2003 show that the temperature in the planet's southern hemisphere has been dropping, despite the fact that these measurements were taken in the early part of its long summer. New Scientist reports: Michael Roman at the University of Leicester, UK, and his colleagues examined data from several of the world's biggest telescopes to figure out how the temperature of Neptune has changed since the first relatively detailed measurements were made in 2003. "Because we are observing Neptune in this southern summer, we basically expect temperatures to be getting slowly warmer in time," says Roman. "But what we saw was that they dropped by about 8C" over the course of 15 years, he says. The observations also revealed a surprise near the planet's south pole. Between 2018 and 2020, an area there warmed by about 11C, an unexpectedly rapid change given that it takes Neptune more than 165 Earth years to complete a circuit around the sun. "A season on Neptune is over 40 years long, so we'd expect these changes to be a lot more gradual," says Roman.

Scientists believe they have found evidence of microbes that were thriving near hydrothermal vents on Earth's surface just 300m years after the planet formed -- the strongest evidence yet that life began far earlier than is widely assumed. From a report: If confirmed, it would suggest the conditions necessary for the emergence of life are relatively basic. "If life is relatively quick to emerge, given the right conditions, this increases the chance that life exists on other planets," said Dominic Papineau, of University College London, who led the research. Five years ago, Papineau and colleagues announced they had found microfossils in iron-rich sedimentary rocks from the Nuvvuagittuq supracrustal belt in Quebec, Canada. The team suggested that these tiny filaments, knobs and tubes of an iron oxide called haematite could have been made by bacteria living around hydrothermal vents that used iron-based chemical reactions to obtain their energy.

Scientific dating of the rocks has suggested they are at least 3.75bn years old, and possibly as old as 4.28bn years, the age of the volcanic rocks they are embedded in. Before this, the oldest reported microfossils dated to 3.46bn and 3.7bn years ago, potentially making the Canadian specimens the oldest direct evidence of life on Earth. Now, further analysis of the rock has revealed a much larger and more complex structure -- a stem with parallel branches on one side that is nearly a centimetre long -- as well as hundreds of distorted spheres, or ellipsoids, alongside the tubes and filaments.

An anonymous reader quotes a report from Space.com: Another piece of space infrastructure for Ukraine is under attack, according to an NBC report. Jammers from Russian forces besieging the country are targeting global positioning system (GPS) satellite signals that are used for navigation, mapping and other purposes, the report said, quoting the U.S. Space Force. "Ukraine may not be able to use GPS because there are jammers around that prevent them from receiving any usable signal," Gen. David Thompson, the Space Force's vice chief of space operations, told NBC Nightly News Monday (April 11). "Certainly the Russians understand the value and importance of GPS and try to prevent others from using it," Thompson added. He noted that Russia has not directly attacked any satellites in orbit, but the Space Force is keeping an eye out for such possibilities.

Specifically, Russia is targeting the Navstar system of satellites used by the United States and made available openly to many countries around the world, Thompson said. (Russia has its own independent system, called GLONASS, while the Europeans have one called Galileo and China has one called Beidou.) Navstar uses 24 main satellites that each orbit the Earth every 12 hours. The system works by sending synchronized signals to users on Earth. Because the satellites move in different directions, the user receives their signals at slightly different times. When four satellites are available, GPS receivers can use their signals to calculate the user's position, often to within just a few feet. In late February shortly after Russia's invasion of Ukraine began, SpaceX's Starlink satellites were activated over the country to help restore internet services destroyed by the Russians. SpaceX CEO Elon Musk later warned that Starlink user terminals in Ukraine could be targeted by Russia and advised users to take precautions.

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.

For the first time the world is in a position to limit global heating to under 2C, according to the first in-depth analysis of the net zero pledges made by nations at the UN Cop26 climate summit in December. From a report: Before these pledges it was more than likely that at the peak of the climate crisis there would be a temperature rise above 2C, bringing more severe impacts for billions of people. Now it is more likely that the peak temperature rise will be about 1.9C. However, the researchers said this depended on all nations implementing their pledges on time and in full, and warned that the policies to do so were not in place. The pledges also include those that developing countries have said will not happen without more financial and technical support. Achieving the pledges needed for the 2C limit was a "historic milestone," and good news, the scientists said. However, they said the bad news was that the cuts in global emissions currently planned by 2030 were way off track to keep the peak below 1.5C. That is the global goal, but currently there is less than a 10% chance of hitting that target.

In a new study published in the journal Nature Biomedical Engineering, researchers from Harvard and MIT detail work they've done on a "living cellular therapeutic device" that promises to protect humans from the harmful side effects antibiotics can have on our guts. Engadget reports: Per Science Daily, they modified a strain of bacteria that is frequently used in cheese production to deliver an enzyme that can break down beta-lactam antibiotics. Many of the most commonly prescribed antibiotics in the US, including penicillin, fall under that family. Using gene editing, they further modified how their bacterium synthesizes the enzyme to prevent it from transferring that capability to other bacteria. The result is a treatment that reduces the harmful effects of antibiotics while still allowing those drugs to do their work.

In a study involving mice, the researchers found their bacteria "significantly" reduced the damage ampicillin did to the test subject's gut microbes and allowed those communities to recover fully after just three days. By contrast, in mice that only received the antibiotic, the researchers saw a much greater loss of microbial diversity. "We are now focusing on getting these living therapies to patients and are finalizing the design of an effective, short, and inexpensive clinical trial," said Andres Cubillos-Ruiz, the lead author of the study.

Amazon workers only make up a third of US warehouse employees, but in 2021, they suffered 49 percent of the injuries for the entire warehouse industry, according to a report by advocacy group Strategic Organizing Center (or SOC). The Verge reports: After analyzing data from the Occupational Safety and Health Administration (OSHA), the union coalition found that Amazon workers are twice as likely to be seriously injured than people who work in warehouses for other companies. The report considers "serious injuries" to be ones where workers either have to take time off to recover or have their workloads reduced, following OSHA's report classification (pdf) of "cases with days away from work" and "cases with job transfer or restriction." The data shows that, over time, the company has been shifting more toward putting people on light duty, rather than having them take time off. The report authors also note that Amazon workers take longer to recover from injuries than employees at other companies: around 62 days on average, versus 44 across the industry.

Amazon employees have said it's not the work itself that's particularly dangerous but rather the grueling pace the company's automated systems demand. Amazon actually had workers go slower in 2020 to help combat COVID-19, which accounts for the notably lower injury rates that year. But, as the report notes, the injuries increased by around 20 percent between 2020 and 2021 as the company resumed its usual pace -- though the injury rates for 2021 were still lower than they were in 2019. [...] Unfortunately, this study's results tell the same story we've been hearing for years. Even with its reduced injury rates in 2020, Amazon workers were still hurt twice as often as other warehouse workers, according to SOC. Further reading: Amazon Workers At 100 More Facilities Want To Unionize (Yahoo Finance)

As climate crisis allows new maritime routes to be used, sooty shipping emissions accelerates ice melt and risk to ecosystems. From a report: In February last year, a Russian gas tanker, Christophe de Margerie, made history by navigating the icy waters of the northern sea route in mid-winter. The pioneering voyage, from Jiangsu in China to a remote Arctic port in Siberia, was heralded as the start of a new era that could reshape global shipping routes -- cutting travel times between Europe and Asia by more than a third. It has been made possible by the climate crisis. Shrinking polar ice has allowed shipping traffic in the Arctic to rise 25% between 2013 and 2019 and the growth is expected to continue. But Arctic shipping is not only made possible by the climate crisis, it is adding to it too. More ships mean a rise in exhaust fumes, which is accelerating ice melt in this sensitive region due to a complex phenomenon involving "black carbon," an air pollutant formed by the incomplete combustion of fossil fuels.

When black carbon, or soot, lands on snow and ice, it dramatically speeds up melting. Dark snow and ice, by absorbing more energy, melts far faster than heat-reflecting white snow, creating a vicious circle of faster warming. Environmentalists warn that the Arctic, which is warming four times faster than the global average, has seen an 85% rise in black carbon from ships between 2015 and 2019, mainly because of the increase in oil tankers and bulk carriers. The particles, which exacerbate respiratory and cardiovascular illness in towns, are short-term but potent climate agents: they represent more than 20% of carbon dioxide equivalent emissions from ships, according to one estimate.