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Raumfahrt - US awaits answers after China cries foul over purported sat threat to taikonauts

26.02.2022

There is one bright spot in the ongoing US-China space traffic brouhaha: Beijing has begun publishing for the first time the basic orbital positions of its crewed space station.

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Photo taken on Jan 6, 2022 at Beijing Aerospace Control Center in Beijing, capital of China, shows the transposition test of the Tianzhou-2 cargo craft using its space station’s robotic arm. (Photo/Xinhua)

WASHINGTON: As of this week, Beijing still has not responded to Washington’s requests for details about its complaint to the United Nations that SpaceX’s Starlink satellites have endangered China’s crewed space station, US officials told Breaking Defense.

“We are still awaiting a direct response from the PRC with information regarding these incidents,” a Space Command spokesperson said in a Feb. 23 email. “The USG has also consistently urged the PRC to utilize its designated points of contact for concerns relating to human spaceflight safety and emergency collision avoidance support.”

A State Department spokesperson told Breaking Defense last week that the US had requested “additional information from the PRC regarding contact information for its human spaceflight team and its conjunction assessment results for the two alleged approaches” about which China issued a note verbale to the UN in December.

The US-China spat was kicked off by that unusual public missive by Beijing in December to the UN Office of Outer Space Affairs complaining that it was forced to move the China Space Station to avoid Starlinks on two recent occasions. The US on Jan. 28 issued its own note verbale to the UN refuting the allegation that Starlink had endangered the taikonauts, and noting that SPACECOM would have provided a warning if that were so.

SPACECOM’s 18th Space Control Squadron operates a network of radar and telescopes on the ground and in space, called the Space Surveillance Network, to keep tabs on satellites and dangerous space junk. It also currently is responsible for providing satellite operators with warnings about potential collisions — a task that includes keeping a public database of spacecraft positions on the Space.Track.org, as well as via directly to foreign operators whose governments have signed bilateral cooperation agreements with SPACECOM.

In the latest round of the public tit-for-tat, Chinese Foreign Ministry Spokesperson Zhao Lijian told reporters on Feb. 10 that not only had China tried to contact US authorities regarding the Starlinks, but that Beijing was ready to establish direct communications links with the US on future close approaches on orbit.

“After the incidents, China’s competent authorities tried multiple times to reach the US side via e-mail, but received no reply. Now the US attempts to use the so-called threshold of emergency collision criteria to shift responsibilities and deflect attention. It is not showing a responsible attitude as a space power. Moreover, it is in no position to unilaterally set a threshold of emergency collision criteria,” he said.

“With a view to protecting the safety of Chinese astronauts and space station, the Chinese side stands ready to establish a long-term communication mechanism with the US side and hopes that the US will take concrete measures to prevent such incident from happening again,” he said.

But US officials reiterated to Breaking Defense that Beijing had not contacted the US at the time of the two incidents.

“The United States has no record of attempts by the PRC to contact Space Command, SpaceX, or any other U.S. entity at any time to express concerns or share information regarding its claims of close approaches,” the State Department spokesperson said.

Nor has Beijing made any move to actually set up any kind of hotline, or asked to sign a bilateral agreement with SPACECOM, according to the SPACECOM and State Dept. spokespersons.

“The U.S. Government has repeatedly sought to improve bilateral sharing of spaceflight information with the PRC for nearly a decade and continues to provide timely emergency collision safety information to the PRC, as it does for all nations,” the State Department spokesperson said.

“We urge the PRC to establish long-term communication mechanism by utilizing previously designated points of contact for concerns relating to human spaceflight safety. We also urge the PRC to register for and maintain a no-cost account on space-track.org,” the spokesperson added. “We continue to seek opportunities to increase and improve communications with all space-faring nations with human spaceflight programs, including the PRC.”

The SPACECOM spokesperson noted that the US has published a “spaceflight safety handbook for space operators” [PDF]  that “explains our collision screening and notification criteria” when two space objects are predicted to cross orbits.

“We note that because the current collision screening process has worked well since the inception of the USG sharing efforts more than a decade ago, the DoD has not made separate distinctions in conjunction criteria for human spaceflight activities,” the spokesperson added.

But the question of how the US and China, as well as other nations and commercial operators, calculate the likelihood of a collision between objects in space is also a source of contention in the Starlink spat.

Nongovernmental experts said Beijing is correct that the US has no international legal authority to set a universal threshold for how close is too close — especially as determine a probability of collision involves more than just simple measurements of the distance between two space objects. Indeed, Washington doesn’t even have any national space traffic regulations that tell US operators when to move their satellites to avoid a predicted collision — if they can, that is, given that neither are there any US regulations requiring operators to enable their satellites to maneuver.

“I agree with China that no one operator can unilaterally set what ‘close’ is. We’ve already seen that play out in the commercial world where different satellite operators have different thresholds for when they take action to maneuver a satellite,” said Secure World Foundation’s Brian Weeden.

Jessica West, of Canada’s Project Plowshares, agreed. “One state should not decide what counts as too close nor have to account for the safety of all objects operating in outer space.”

There is one bright spot in the ongoing brouhaha, however: Following Zhao’s statement, China began publishing for the first time the basic orbital positions of its space station on the website of the China Manned Space office. This allows other space operators to know roughly where the station is at any one time.

“Sharing of two-line elements of the China Space Station by the China Manned Space Agency … is a positive first step in transparency,” the State Department spokesperson said. “Proactive, timely, and comprehensive data sharing, similar to what NASA provides for the International Space Station, is essential for human spaceflight safety.”

Quelle: BREAKING DEFENSE

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