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A crowd watches three astronauts blast off onboard the Long March-2F at China's Jiuquan Satellite Launch Center on May 30, 2023. The same rocket model was used in December to launch the secretive Chinese spacecraft that returned to earth earlier this month.

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Hong Kong CNN  — 

A Chinese “reusable experimental spacecraft” believed to be the country’s secretive space plane has landed back on Earth after more than eight months in orbit – the latest development in a largely covert race between the United States and China to hone such technology.

China’s spacecraft blasted into orbit last December – two weeks ahead of the latest launch of the US military’s own Boeing X-37B uncrewed space plane – on the third known orbital mission of such a Chinese spacecraft.

Some 268 days later, the spacecraft returned to an unnamed landing site, according to a brief September 6 announcement from state news agency Xinhua, which declared its test mission a “complete success.”

China’s development of the vehicle, about which little is publicly known, comes after recent years of striving to catch up to the US, long the world’s preeminent space power, for dominance in orbit and beyond.

Here’s what we know – and don’t – about China’s space plane.

What is a space plane – and isn’t this old technology?

The term “space plane” often evokes NASA’s Space Shuttle, which flew 135 missions from 1981 to 2011, carrying astronauts into orbit and helping to construct the International Space Station. It might also recall the Soviet Union’s ill-fated Buran space shuttle, which completed one successful uncrewed flight in 1988 before being discontinued.

But the newer planes currently being tested in orbit by the US and China are believed to be smaller than the shuttle and uncrewed. The US X-37B is operated by the military, while China has not said whether the program believed to be linked to its recently landed spacecraft is civilian or military.

Space planes are generally reusable craft similar to both an airplane and a spacecraft in that they can fly in Earth’s atmosphere and in space. Both the Chinese spacecraft that recently returned to Earth and the US’ X-37B, which has conducted seven missions since its 2010 debut, are launched on rockets into outer space but land like airplanes on runways, experts say.

Space planes are valued for their potential to carry out a range of missions in orbit and help countries respond quickly to developments in space, while advancing reusable spacecraft technology that could be used for more regular human space travel in the future.

“It’s no surprise that the Chinese are extremely interested in our space plane, and we’re extremely interested in theirs,” US Space Force chief of operations Gen. Chance Saltzman told reporters at a conference in December.

“It is a capability – the ability to put something in orbit, do some things, and bring it home and take a look at the results is powerful.”

Hulton Archive/Getty Images
Space Shuttle Columbia lifts off from NASA's Kennedy Space Center in Florida on April 12, 1981, marking the first flight of the US Space Shuttle Program.

What do we know about China’s space plane program?

Not too much.

China has never said what specific technologies the spacecraft has tested, or released any photographs of it, since it began operating in orbit in 2020.

A video shared on the social media channel of state-backed space contractor China Aerospace Science and Technology Corporation announcing the spacecraft’s September 6 landing featured a banner instead of images. The text read: “It’s too advanced to be shown.”

Even the name of the spacecraft that landed back on Earth has not been confirmed by the Chinese government, though observers suspect it is the “Shenlong” space plane, which has been under development for two decades.

Other space plane projects under development in recent years in China have been publicly and officially described as civilian projects, while the official purpose of Shenlong remains unconfirmed, experts say.

It’s also unknown if this is the same vehicle or another in the same series that completed two previous missions – the first in 2020 lasted two days and the second beginning in 2022 lasted 273. All are believed by analysts to have ended with landings at the secretive Lop Nur military facility in Xinjiang, in the country’s far northwest.

An official announcement after its December 14 launch said the spacecraft would “carry out reusable technology verification and space science experiments as planned, providing technical support for the peaceful use of space.”

But space observers are able – via open-source data, imaging and positional measurements – to monitor what the vehicle has been up to in space, including tracking the release of what they say is a suspected “sub-satellite” in late May and its apparent efforts to maneuver around the object. That follows similar exercises on previous tests missions.

“This capability to maneuver close to another object could be used for inspection of space assets, or potentially the clearing of orbits of space debris. But they could be used for nefarious purposes, including interception of signals or the physical damaging of other spacecraft,” said Juliana Suess, a research fellow for space security at London-based defense think tank the Royal United Services Institute, or RUSI.

Are there military applications?

China’s space plane development comes as a growing number of countries are paying attention to the deepening connections between security on Earth and in space – and vying for so-called counterspace technologies with the potential to disrupt or even destroy adversaries’ assets in space.

China has been explicit in recent announcements about the peaceful purposes of the spacecraft and its other endeavors in space, though analysts say it is among world powers developing counterspace capabilities.

The state media announcement of the spacecraft’s landing said it would “pave the way for more convenient and affordable round-trip methods for the peaceful use of space in the future.”

Analysts say there’s no evidence that China’s space plane is being designed to act as a counterspace weapon, but that information and capabilities gained on its missions could have dual-use applications.

“Anything that China learns from operating its space plane, no matter its main purpose, will benefit its counterspace efforts,” said Clayton Swope, deputy director of the Aerospace Security Project at the Center for Strategic and International Studies think tank in Washington.

“In addition to maturing space technologies, it’s allowing China to mature its muscle memory for operating in space. It’s concerning how China could apply those learnings to counterspace weapons,” he said.

Joe Skipper/Reuters
The US military's X-37B spaceplane lifts off on its seventh mission to orbit atop a SpaceX Falcon Heavy on Friday, December 28.

How does this compare with the US’ X-37B space plane?

It’s hard to compare China’s space plane with the US’ X-37B, due to the high level of secrecy around both programs.

The X-37B has been in operation for years longer than China’s space plane and has stayed in orbit significantly longer, a record set during its sixth mission of a 908-day journey before returning to Earth in November 2022.

The US Space Force, which oversees the X-37B, describes it as a reusable, uncrewed spacecraft that “strengthens the United States’ future in space by conducting technology experiments that expedite the development of next-generation capabilities.”

Its latest mission includes tests operating in new regions of orbit, experimenting with space domain awareness technologies to monitor objects in space, and investigating radiation effects on NASA materials, including plant seeds, the force has said.

But observers have also raised questions about the activities of the space plane, including its own deployment of multiple small satellites.

The level of secrecy around the deployment of those satellites “may indicate they are part of a covert intelligence program, but it may also indicate the testing of offensive technologies or capabilities,” the independent US-based Secure World Foundation noted in a recent report, while pointing to “similar behavior in terms of secret deployments” from the Shenlong space plane.

Observers also note that China is likely using the US program as a benchmark for its own.

“The fact they now have a reusable spacecraft just by itself shows how far they have come (and) the fact it was up for so long, and returned safely,” said Brendan Mulvaney, director of the China Aerospace Studies Institute, a US Air Force think tank, noting the Chinese claim of mission success earlier this month.

“All of that means they are putting in the time, effort, and investments, to make it work.  China is the undisputed No. 2 space power and is aiming to close the gap with the US in military, commercial, and scientific realms, all at the same time,” he said.