China is developing ways to de-orbit space junk. Should we be worried?

China is developing the capability to remove space debris from orbit, according to a top official.

In recent years, China's space activities have grown tremendously, with an operational space station in low Earth orbit (LEO), a greatly increased rate of launches and plans for multiple constellations consisting of thousands of satellites. The growth of the country's presence in orbit also raises issues of sustainability.

Bian Zhigang, vice administrator of the China National Space Administration (CNSA), was asked about what challenges this ramp-up poses for long-term sustainability in space at the International Astronautical Congress in Sydney, Australia, during a Heads of Agencies plenary session on Sept. 29.

China will work on its space situational awareness capabilities in order to track objects and assess the chances of collisions, while also coordinating with other countries, Bian said. It will also take a more proactive role with regard to debris.

"Now China is promoting the space debris mitigation top level planning to promote monitoring and alerting," Bian said through an interpreter. "And also, most importantly, is, we are currently researching on the active removal of this space debris on orbit."

No details about capabilities, technologies or mission timelines were offered. China's actions to address the issue of debris will no doubt be widely welcomed, but they may also spark some concerns.

Active debris removal is a dual-use capability, meaning it can be used for civilian purposes but also for military ends. The ability to remove a defunct rocket stage or satellite from orbit could also be used to target an adversary’s spacecraft.

China is currently conducting experiments high above the Earth, with the Shijian-21 and Shijian-25 satellites apparently conducting rendezvous and proximity operations (RPOs), docking and performing a first-ever refueling in geostationary orbit.

However, unlike some other RPOs conducted by other countries and companies, China has released no images, updates or information about the activities. The opaque nature of the mission could, if replicated with future active debris removal tests, generate more suspicion than good will.

As one of the most active countries in terms of launches over the past decade, China has a number of spent rocket stages and dead satellites in orbit, whose removal from LEO would be a boost to the sustainability of crowded orbits.

Bian also reaffirmed that Chinese policies and regulations require satellite operators to deorbit satellites, or at least lower their orbits, near the end of their lifetimes

Further indications of plans and intentions may follow in future policy documents released by the CNSA. Its actions will likely be closely watched for transparency and international collaboration.