After nine months in orbit, China's mysterious space plane has landed for the second time, making the nation one of the few entities to successfully launch and recover a reusable spacecraft.
"The complete success of this experiment marks a significant breakthrough in our country's research on reusable spacecraft technology," Xinhua, a Chinese state media agency, reported earlier this month.
However, the Chinese government has released very little additional information about the craft; the details of its design, capabilities and performance remain hazy.
Experts think the Chinese plane is likely similar to the Boeing X-37B, a U.S. space plane that debuted in 2010. Kevin Pollpeter, a research scientist at the Center for Naval Analyses, told Nature.com that the reveal of X-37B sparked concern within the Chinese government over the craft's military potential. It's possible that this spurred the country's space program, which is closely tied to its military, to start developing its own version, Pollpeter said.
Like the X-37B, the Chinese craft appears to be uncrewed and relatively small. It probably first flew in September 2020, making a short two-day stint into orbit before returning to the ground. Its most recent mission began in August 2022, when it took off on a Long March 2F rocket from the Jiuquan Satellite Launch Center in northern China, according to a report from the Washington, D.C.-based Center for Strategic and International Studies (CSIS). The exact purpose of the mission remains unclear.
According to the CSIS report, the craft released an "object" into orbit sometime in October. The object apparently disappeared in January, only to suddenly reappear on satellite tracking radar in March. Experts believe this could indicate that the plane has some sort of satellite removal capability, such as a robotic arm.
"[The Chinese] have been working a lot with robot arms in other contexts, like the Chinese space station," Jonathan McDowell, an astrophysicist at the Harvard & Smithsonian Center for Astrophysics, told Nature.
If that's the case, then the plane's primary purpose might be to repair damaged satellites or remove orbital debris. However, this does not rule out military capabilities — either for the Chinese plane or for the X-37B. Until more details come out, however, the best we can do is speculate.
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Joanna Thompson is a science journalist and runner based in New York. She holds a B.S. in Zoology and a B.A. in Creative Writing from North Carolina State University, as well as a Master's in Science Journalism from NYU's Science, Health and Environmental Reporting Program. Find more of her work in Scientific American, The Daily Beast, Atlas Obscura or Audubon Magazine.