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China’s Out-of-Control Rocket Predicted to Crash on July 31

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The Long March 5B shortly before its launch on July 24, 2022.
Photo: Liu Huaiyu (AP)

Experts are predicting that the gigantic core stage of a recently launched Long March 5B rocket will crash to Earth within a matter of days, but the precise location remains impossible to guess.

The Long March 5B rocket blasted off on July 24 from the Wenchang Space Launch Site in Hainan. The rocket successfully delivered the Wentien lab to low Earth orbit, where it docked with China’s Tiangong space station some 13 hours later.

Like previous launches of Long March 5Bs, however, the core stage—which lacks controlled reentry provisions—entered into an Earth orbit, and a quickly deteriorating one at that. The 25-ton (22.5-metric-ton) core stage, designated CZ-5B, is now poised to make an uncontrolled re-entry.

Experts with The Aerospace Corporation’s Center for Orbital Reentry and Debris Studies (CORDS) have calculated a likely date for the arrival of this wayward rocket body. They analyzed data from the U.S. Space Force’s Space Surveillance Network to devise the estimate, which suggests the rocket will return to Earth on July 31 at 7:52 a.m. UTC (3:52 a.m. ET), with an error bar of plus-minus 22 hours.

“For tracking and predicting reentries, our team uses public data sets that are generated when an object being tracked passes over one of a collection of sensors across the planet,” Marlon Sorge, technical fellow and executive director at The Aerospace Corporation’s CORDS, explained to me in an email.

The Space Surveillance Network tracks objects in space using radar and optical sensors at multiple locations around the planet. These sensors “observe and track objects that are larger than a softball in low Earth orbits and basketball-sized objects or larger in higher geosynchronous orbits,” Sorge said. “The sensors can determine which orbit the objects are in, and that information is used to predict close approaches, reentries, and the probability of a collision.”

The expected geographical range remains excessively high, with the rocket body potentially reentering somewhere between 41 degrees north and 41 degrees south latitude. “It is still too early to determine a meaningful debris footprint,” the company said in a tweet. The Aerospace Corporation will be updating its tracking page as the estimate gets refined over time.

“Due to the uncontrolled nature of its descent, there is a non-zero probability of the surviving debris landing in a populated area—over 88 percent of the world’s population lives under the reentry’s potential debris footprint,” according to an Aerospace Corporation statement. The company says that objects of this size don’t burn up in the atmosphere and that typically 20% to 40% of the total mass of a large object will reach the ground, depending on the object.

Normally, core stages don’t reach orbit and are instead guided into the ocean or over sparsely populated areas. In the case of SpaceX’s Falcon 9 reusable rocket, the first stages perform controlled vertical landings on the surface or on drone ships.

This will mark the third time that the core stage of a Long March 5B has entered orbit after launch and fallen back to Earth in an uncontrolled manner, so this trait appears to be a feature of the rocket rather than a bug. Two years ago, debris from an out-of-control core stage fell onto an inhabited area along the west coast of Africa, while debris from a Long March 5B launched last year crashed into the Indian Ocean near the Maldives. In both cases no one was hurt, but scientists have recently raised concerns that, with all the rockets being launched these days, someone might eventually get badly injured or even killed.

“Spacefaring nations must minimize the risks to people and property on Earth of re-entries of space objects and maximize transparency regarding those operations,” Bill Nelson, NASA administrator, said in an agency statement in wake of the 2021 incident. “It is clear that China is failing to meet responsible standards regarding their space debris. It is critical that China and all spacefaring nations and commercial entities act responsibly and transparently in space to ensure the safety, stability, security, and long-term sustainability of outer space activities.”

China is planning to launch its Mengtian space station module this October, which means we’ll get to do this all over again in just three month’s time.

More: Russia says it’ll leave the ISS after 2024.



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China Tests Drag Sail For Removing Space Junk

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This kite-like space sail will help deorbit a rocket component within two years.
Image: Shanghai Academy of Spaceflight Technology

Engineers in China have successfully deployed an ultra-thin sail attached to a rocket part to expedite its departure from low Earth orbit and reduce the amount of space junk aimlessly floating above our planet.

The 269-square-foot (25-square-meter) sail unfurled after launching from a Long March 2D rocket on June 24. Although the mission was not publicized beforehand, the Shanghai Academy of Spacecraft Technology (SAST) announced a few days later that the drag sail had been successfully deployed to assist with the deorbiting of the rocket component, which won’t happen for another two years or so.

When unfurled, the kite-shaped sail increases the atmospheric drag working against the object it’s attached to, thereby accelerating orbital decay. The rocket component will then meet its fate much sooner, deorbiting and burning up in Earth’s atmosphere on its way down. It’s a potential low-cost solution to the ever-growing problem of space debris.

The recently launched drag sail is made from super thin material, about the same thickness as one-tenth the diameter of a human hair. The component that it’s currently attached to, the payload adapter of the rocket’s upper stage, weighs around 661 pounds (300 kilograms) and is orbiting the Earth at an altitude of approximately 305 miles (491 kilometers), according to SAST. The rocket is expected to get dragged down to lower altitudes with increased friction due to the sail and reenter Earth’s atmosphere in about two years.

China has been a bit reckless lately when deorbiting its rockets. In April, debris that was likely caused by a Chinese rocket that disintegrated on re-entry fell onto a western village in India. Similarly in May 2021, a Chinese Long March 5B rocket fell into the Indian Ocean after making an uncontrolled reentry through Earth’s atmosphere. A year earlier in May 2020, another incoming Long March 5B rocket caused pieces of debris to fall onto two villages in Cote d’Ivoire, damaging people’s homes.

The drag sail will help remove the rocket from Earth’s orbit sooner than it would have on its own, but it’s not clear whether China will account for where pieces of the rocket might fall in order to avoid populated areas.

It’s hoped that the new technology will aid in clearing orbiting space junk. The Department of Defense’s global Space Surveillance Network is currently tracking more than 27,000 pieces of orbital debris, and many more smaller pieces in the near-Earth environment, according to NASA. Ideally, as countries continue to expand their space programs, they will also figure out a way to deorbit their spacecraft not only more quickly, but also less harmfully.

More: The Coolest Images Taken by NASA’s New Horizons Spacecraft.

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Russian Motor Spontaneously Explodes in Orbit, Creating Debris Cloud

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Space agencies are trying to figure out ways to mitigate the effects of space debris.
Photo: Arne Dedert (AP)

An old Russian motor that’s been aimlessly floating through space for more than a decade has finally met its demise in a sudden explosion, producing at least 16 shards of orbital debris that now threaten satellites and other objects.

On Tuesday, the U.S. Space Force’s 18th Space Defense Squadron confirmed through Twitter that a SOZ ullage motor exploded in space on April 15. At least 16 pieces of debris were created by the event, which the defense squadron is now tracking. The motor was used to launch three Russian GLONASS satellites in 2007, boosting them into the right orbit once they were in space. The motor had been orbiting idly in space since then, but with leftover high energy rocket propellant still packed inside.

“It’s sort of like a little bit of a time bomb, but without an actual timer,” astrophysicist Jonathan McDowell from the Harvard-Smithsonian Center for Astrophysics told Gizmodo.

Something likely happened within the motor that involved the rocket propellant, causing it to explode. Unfortunately, this isn’t the first time a discarded SOZ ullage motor has made a big mess in space. At least 54 of these motors have already exploded, and there are about 64 of them still in orbit, according to McDowell. This latest motor breakup incident is adding to the mounting problem of space debris, or space junk, caught in Earth’s orbit.

“When I saw this, I was massively unsurprised,” he said. “These things have been popping off once or twice a year for many years, and it’s really been a problem.” The motor is an older Soviet rocket design left over from the Cold War, whereas newer designs of spacecraft are designed to avoid these issues. “This particular issue of leftover rocket stages blowing up has mostly been designed out in modern rockets,” McDowell said. “The best practice nowadays is to passivate spacecraft when they’re at the end of their mission.” Spacecraft passivation is the removal or deactivation of all potential sources of explosions.

But even if these older designs are no longer being sent to space, the pre-existing population of these relic motors could continue to generate more debris, and create further risks to satellites, which could in turn result in even more debris—a serious problem known as Kessler Syndrome.

More than 27,000 pieces of orbital debris are tracked by the Department of Defense’s global Space Surveillance Network (SSN) sensors, with many more smaller pieces of debris in the near-Earth environment, according to NASA. These uncontrolled pieces of junk, whether a retired satellite or a small chunk of metal, travel at high speeds, running a potential risk of crashing into an operational spacecraft and causing considerable damage.

In June 2021, for example, a piece of space junk crashed into the International Space Station, damaging one of its robotic arms. Later in November, astronauts aboard the ISS had to take shelter from a cloud of space debris generated by the destruction of the defunct Russian satellite Kosmos-1408—the result of a reckless Russian anti-satellite test. China’s anti-satellite test in 2007 created more than 3,000 pieces of large debris.

Space agencies are hoping to find solutions to the ongoing orbital littering, with the European Space Agency recently commissioning the first debris removal mission, currently slated for a 2025 launch. The ClearSpace-1 spacecraft will feature four arms designed to clean up space junk in Earth’s orbit.

Big pieces of space debris “have the most risk of not just blowing up, but of hitting each other and creating lots more debris,” McDowell said. “And so if you want to avoid a sort of chain reaction, then getting rid of the big ones is what you want to do, and I think that that is going to happen.”



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Astronauts Forced to Take Shelter as Debris Cloud Threatens Space Station

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The International Space Station
Image: Roscosmos

All seven astronauts currently aboard the International Space Station are having to take shelter inside their respective spacecraft owing to the sudden appearance of a debris cloud in orbit, the source of which remains unclear.

Information is slowly trickling in, but we do know that the ISS is currently functioning normally and that all seven crew members are healthy and safe. The crew had to take shelter earlier this morning due to the sudden appearance of an orbiting debris field. The unexplained breakup of the defunct Russian satellite Kosmos-1408 is currently the leading candidate for the source of the orbiting debris cloud.

NASA astronauts Raja Chari, Tom Marshburn, Kayla Barron, and ESA astronaut Matthias Maurer are sheltering inside a SpaceX Crew Dragon docked to the ISS, while Russian cosmonauts Anton Shkaplerov, Pyotr Dubrov, and NASA astronaut Mark Vande Hei are inside a Soyuz capsule, reports Russian state-owned news agency TASS. The astronauts could use these spacecraft to safely return to Earth in the event the ISS is damaged by the debris.

A live feed of NASA mission control is available, allowing you to follow the events as they’re happening.

In a tweet, Roscosmos said the crew is “routinely performing operations according to the flight program,” and that the threatening “object” has “moved away from the ISS orbit.” By “object,” the Russian space agency is referring to the debris field. The “station is in the green zone,” Roscosmos added.

“Friends, everything is regular with us!,” tweeted Shkaplerov. “We continue to work on the program.”

Despite these words of reassurance, operations aboard the ISS are most certainly not back to normal. Mission controllers are continually providing countdowns of each debris field transit (i.e. the closest approach of the debris field to the ISS). At 10:32 a.m. ET, controllers provided instructions for the NASA crew to temporarily enter into the Columbus module to perform some quick tasks and to collect personal items should they have to remain inside Dragon overnight (a possible indication that this could take a while).

The debris field transits were happening about once every 93 minutes at first, but now they’re happening about once every 30 to 40 minutes. In an email, Harvard University astrophysicist Jonathan McDowell said that, assuming it’s a debris field caused by a broken-up satellite, “there will be a big error bar on whether there is risk to ISS, hence the caution.”

The source of the debris field remains unconfirmed, but its sudden appearance coincides with reports that Russia has conducted an anti-satellite (ASAT) weapons test. In a tweet, Gunter Krebs, a physicist and editor of Gunter’s Space Page, said the target was an “old Soviet Tselina-D SIGINT satellite called Kosmos-1408 (1982-092A) launched in 1982, which has been dead for decades,” and that ”14 debris objects have been tracked.” But Krebs cautions: “So far no confirmation from official sources.”

U.S. Space Force “is aware of a debris-generating event in outer space” and is “working to characterize the debris field and will continue to ensure all space-faring nations have the information necessary to maneuver satellites if impacted,” tweeted space reporter Joey Roulette from the New York Times.

Today’s incident comes less than a week after the ISS had to make an emergency maneuver to evade potentially threatening space junk. In that case, it was a remnant of the Fengyun-1C weather satellite, which China deliberately destroyed in 2007 as part of an anti-satellite missile test. India did something similar in 2019, joining the United States, Russia, and China as countries that have tested anti-satellite weapons. Currently, the use of ASATs “occupy a gray zone” when it comes to international arms control, writes Talia M. Blatt from Harvard University.  

This is a developing story and we will update this article as we learn more.



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