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The U.S. and Russia work together to rescue stranded astronauts

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As the U.S. and Russia are facing off over the invasion of Ukraine, the two adversary nations are quietly cooperating on another life-or-death matter: making sure astronauts are not stranded in space.

On Dec. 15, International Space Station mission control halted a planned spacewalk aboard the orbiting laboratory because of a startling new problem. A Russian Soyuz space capsule docked to the facility was suddenly spewing gobs of fluid into space. The dramatic leak, which saw a 0.8 millimeter hole empty the capsule’s radiator of cooling fluid, has left NASA and Russia’s Roscosmos space agency with a new problem — how to safely transport two cosmonauts and one astronaut who had been scheduled to return home in the now-damaged capsule in March. The capsule also functioned as the station’s emergency escape pod for those three, leaving them stranded if a serious problem develops in the station’s living quarters.

The situation — one of the more dangerous the ISS has faced in years — comes decades into the two nations’ long partnership running the station, which costs the U.S. $1.3 billion a year to operate. Yet despite the war in Ukraine dividing the two nations, the U.S. and Russia are working on solving the problem together, with a decision expected this month — reflecting three decades of interdependence at the ISS. Born of the end of the Cold War, the space station’s role as a geopolitical symbol of cooperation between the world’s most formidable nuclear powers has long outweighed its scientific achievements.

“Up to now, the White House explicitly has built a wall around ISS and space cooperation that kept it separate from the general pattern of U.S.-Russian relations,” said John Logsdon, a professor emeritus at George Washington University and founder of its Space Policy Institute. That was particularly true in the last decade, he added, when the U.S. relied solely on Russia to launch astronauts to the space station, until the first launch of SpaceX’s Dragon capsule in 2020.

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“So there has been an explicit, but unstated and understood, policy that as long as Russia keeps up its part of the bargain in the partnership that we would not do anything influenced by external factors like Crimea or Ukraine.”

The busted Soyuz and potentially stranded spacefarers are just the latest episode in this long-running marriage of necessity.

“We have a crew member on this vehicle. And so, Roscosmos has reached out to us,” said NASA space station official Joel Montalbano in a December briefing for reporters. “The teams are going back and forth. We’re constantly exchanging data.”

“If we have some technical discussion among us or inside on the Russian side, then we share results of the discussion with our partners,” added Roscosmos’ Sergey Krikalev at the same briefing.

If the analysis, expected this month, concludes that a return trip on the damaged Soyuz would endanger the returnees, astronaut Frank Rubio and cosmonauts Dmitri Petelin and Sergey Prokopyev, Russia might have to send up an empty Soyuz capsule to bring them home instead sometime in February. NASA has also reached out to SpaceX about returning the astronauts home in a Dragon space capsule, which normally carries four astronauts but has the capacity for seven in an emergency.

“In space, you cooperate and come to each other’s aid, just like Antarctica or Mount Everest, even if on the ground you are practically at war,” said space journalist Keith Cowing of NASA Watch. “This is like a rescue at sea.”

Just like a car with a busted radiator, the Soyuz capsule will overheat with a radiator emptied of cooling fluid. The capsule now relies on air from the station for cooling, but closing its hatch saw temperatures inside rise to 104 degrees Fahrenheit. That’s even before sending it home to Earth on a reentry burn through the atmosphere, when temperatures inside would normally rise even with a functioning cooling system.

Most likely, the Russians will conclude they have to send an empty Soyuz capsule ahead of the March return mission to carry Rubio, Petelin and Prokopyev home, said Cowing. “In some ways, the Russians are even more conservative than we are, so that wouldn’t surprise me.” That will require rescheduling launches, experiments, crew rosters, spacewalks, maintenance and a host of other decisions aboard the orbiting lab, doubtless taking up a lot of planning time at the space agencies, he added. “It is a tribute to space cooperation that they can plan this, with everything else going on. Kind of a lesson for us on Earth.”

Orbital debris

A meteor shower passed by the space station on the day of the leak. However, its direction did not match the orientation of the hole in the Soyuz, said Krikalev, making it still a bit uncertain whether the leak’s cause was a space impact or a mechanical problem. Later camera work showed an exterior hole in the Soyuz about 4 millimeters across above the smaller hole in the radiator line. A micrometeorite that made such a hole would be too small to track and offer station managers warning it was coming, he added.

Traveling at 15,000 mile-per-hour “hypervelocity” orbital speeds, even a paint chip can blast holes in space station walls. More than 27,000 pieces of space junk, just the stuff big enough to be tracked by the Defense Department’s global Space Surveillance Network, litters the sky around Earth.

“Here’s the thing: The amount of stuff we launch is greater than the stuff that is reentering and burning up. So that means the amount of space traffic and space debris is increasing,” said astrodynamicist Moriba Jah of the University of Texas at Austin. “I’m amazed how infrequently we see these sort of things happening. I’d expect to see them.” Given increases in space debris in recent years, an impact from a tiny piece of space junk, (“something half the size of a bullet going 15 times faster than a bullet,” said Jah) wouldn’t be a surprising explanation for the Soyuz leak.

“We have to look at how well that system was shielded and how it was mitigated,” said Jah. “Humans just can’t think of everything that goes into one of these ‘random’ events ahead of time.”

Although the spew of fluid into space was impressive, Montalbano doubted whether the drops would cause problems for the structure of the space station. “It boils off very quickly. And so, we’re not concerned with any contaminants left on board,” he said.

In the 1990s, Soviet radar reconnaissance satellites leaked hundreds of inch-wide cooling liquid droplets some 370 to 620 miles above Earth — and the space station’s orbit. Whether the newer droplets from the Soyuz will coalesce to form a similar cloud of orbital debris to harry other satellites or the station is a “tricky problem,” said micrometeorite impact expert William Schonberg of the Missouri University of Science and Technology.

Most likely, the liquid will evaporate in orbit, said Schonberg, but without somehow running an experimental recreation of the event, “it’s going to be difficult to say whether or not any, some or most of the leaking coolant will remain in orbit and negatively affect those who encounter it next.”

The International Space Station has weathered hundreds of micrometeor strikes in more than two decades of operations, including ones on windows and solar panels. Heat-dissipating radiators on the station are hardened against such strikes with fluid lines buried under shielding. The leading face of the station is at particular risk for micrometeorite impacts as it circles the Earth once every 90 minutes, traveling at 5 miles per second.

Marriage of necessity

The Soyuz leak comes amid heightened concerns about orbital debris tied to Russia conducting an antisatellite missile test last year, blowing up one of their own derelict spy satellites. The blast, called “reckless and dangerous” by NASA Administrator Bill Nelson, left at least 1,500 trackable fragments in orbit.

“If the coolant leak turns out to have come from the debris created by that Russian antisatellite test, it wouldn’t surprise me,” said Jah. “Mother Nature is going to show us the unintended consequences of our actions. That could be the real point of this event.”

Even earlier in 2018, a drill hole in a Soyuz aboard the space station, apparently made before its launch, raised tensions between the U.S. and Russia. A Russian space official claimed an astronaut had made the hole in a bid to return home early, a claim dismissed by NASA officials. The hole was filled with epoxy.

Such increasing tensions, with repeated Russian claims of backing out of the station, have withered away any official interest in a continued space partnership, even without the war in Ukraine. NASA has committed to continue operating the space station through 2030. Built of a combination of U.S., Russian and international parts, the orbiting lab has quietly set endurance records for human life in space and set a medical baseline for future moon or Mars explorers.

“It was back in the 1990s, a marriage of necessity,” said Logsdon. Russia needed the space station partnership to sustain its human space program at the end of the Cold War. NASA meanwhile needed the Russian buy-in to make geopolitics a selling point for the orbiting lab. “But it was a multi-decade undertaking, so you have to live with the consequences of past decisions,” said Logsdon. “I don’t think there is a chance of a follow-on intimate partnership along these lines now.”

Thanks to Lillian Barkley for copy editing this article.

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An asteroid will whip by Earth tomorrow in one of closest approaches ever recorded

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An asteroid the size of a delivery truck will whip past Earth on Thursday night, one of the closest such encounters ever recorded.

NASA insists it will be a near miss with no chance of the asteroid hitting Earth.

The U.S. space agency said Wednesday that this newly discovered asteroid will zoom 3,600 kilometres above the southern tip of South America. That’s 10 times closer than the bevy of communication satellites circling overhead.

The closest approach will occur at 7:27 p.m. ET.

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Even if the space rock came a lot closer, scientists said most of it would burn up in the atmosphere, with some of the bigger pieces possibly falling as meteorites.

NASA’s impact hazard assessment system, called Scout, quickly ruled out a strike, said its developer, Davide Farnocchia, an engineer at the agency’s Jet Propulsion Laboratory in Pasadena, Calif.

“But despite the very few observations, it was nonetheless able to predict that the asteroid would make an extraordinarily close approach with Earth,” Farnocchia said in a statement.

“In fact, this is one of the closest approaches by a known near-Earth object ever recorded.”

Asteroid spotted by amateur astronomer in Crimea

Discovered Saturday, the asteroid known as 2023 BU is believed to be 3.5 to 8.5 metres across.

It was first spotted by Gennady Borisov, the same amateur astronomer in Crimea who discovered an interstellar comet in 2019.

Within a few days, dozens of observations were made by astronomers around the world, allowing them to refine the asteroid’s orbit.

The asteroid’s path will be drastically altered by Earth’s gravity once it zips by. Instead of circling the sun every 359 days, it will move into an oval orbit lasting 425 days, according to NASA.

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Nuclear-powered spaceships? U.S. plans for 2027

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WASHINGTON –

The United States plans to test a spacecraft engine powered by nuclear fission by 2027 as part of a long-term NASA effort to demonstrate more efficient methods of propelling astronauts to Mars in the future, the space agency’s chief said on Tuesday.

NASA will partner with the U.S. military’s research and development agency, DARPA, to develop a nuclear thermal propulsion engine and launch it to space “as soon as 2027,” NASA administrator Bill Nelson said during a conference in National Harbor, Maryland.

The U.S. space agency has studied for decades the concept of nuclear thermal propulsion, which introduces heat from a nuclear fission reactor to a hydrogen propellant in order to provide a thrust believed to be far more efficient than traditional chemical-based rocket engines.

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NASA officials view nuclear thermal propulsion as crucial for sending humans beyond the moon and deeper into space. A trip to Mars from Earth using the technology could take roughly four months instead of some nine months with a conventional, chemically powered engine, engineers say.

That would substantially reduce the time astronauts would be exposed to deep-space radiation and would also require fewer supplies, such as food and other cargo, during a trip to Mars.

“If we have swifter trips for humans, they are safer trips,” NASA deputy administrator and former astronaut Pam Melroy said Tuesday.

The planned 2027 demonstration, part of an existing DARPA research program that NASA is now joining, could also inform the ambitions of the U.S. Space Force, which has envisioned deploying nuclear reactor-powered spacecraft capable of moving other satellites orbiting near the moon, DARPA and NASA officials said.

DARPA in 2021 awarded funds to General Atomics, Lockheed Martin and Jeff Bezos’ space company Blue Origin to study designs of nuclear reactors and spacecraft. By around March, the agency will pick a company to build the nuclear spacecraft for the 2027 demonstration, the program’s manager Tabitha Dodson said in an interview.

The joint NASA-DARPA effort’s budget is US$110 million for fiscal year 2023 and is expected to be hundreds of millions of dollars more through 2027.

Reporting by Joey Roulette; Editing by Chizu Nomiyama and David Gregorio

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The green comet ZTF returns to the solar system 50,000 years later… and it will be visible from Earth

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For astronomy enthusiasts, February 1 is marked in red on their calendars. The reason: it is not every day that there is a chance to see a green comet.

In fact, it is the first time in 50,000 years that C/2022 ZTF will return to the solar system. And it will be early next month when it will reach its closest position to Earth.

Specifically, the green comet ZTF will pass 42 million light years from our planet. Experts are not 100 percent sure whether it will be visible from the surface without the use of any instrument. However, if we have specific astronomy binoculars or telescopes, we will be able to see it without any problem.

As usually happens in these cases, the best places to observe the comet, this one or any other, are places with little artificial light. That is to say, we should move away from urban centres and it is preferable to do so in the hours before dawn.

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Un cometa brillante, visto desde California.Getty

Why is comet ZTF green?

Comet ZTF has a brightness and a colour that, although not unique, is clearly distinctive. Its hue is due to the fact that it is composed, among other materials, of diatomic carbon.

When it comes into contact with sunlight, the decomposition of this element causes the gas to acquire this spectacular colour.

Comet ZTF was discovered in March 2022

Un telescopio apunta al cielo.
Un telescopio apunta al cielo.Getty

Frank Masci and Bryce Bolin of the Palomar Observatory in California were responsible for spotting the striking comet ZTF in the sky. It is so named because its discovery is part of the Zwicky Transient Facility surveillance programme, which uses the powerful Schmidt telescope at the facility.

Initially, the scientists responsible for the discovery thought it was an asteroid, but they quickly realised that this was not the case. Despite the striking colour of this comet, experts advise keeping expectations low. In any case, it is an event that has aroused great interest in the community.

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