China’s space congestion complaint may prompt global action

A pair of dangerously close space encounters is adding to tensions between the United States and China, while underscoring the potential peril to astronauts as satellite constellations and debris proliferate in orbit.

Two SpaceX satellites had near misses with China’s space station earlier this year — one of them within 2.5 miles — in the latest sign of dangerous overcrowding in low Earth orbit.

In both instances, the orbiting lab made evasive maneuvers to avoid the Starlink satellites operated by Elon Musk’s space venture.

The margin for a near-miss in October could have been as little as a few hundred yards if the astronauts on board the space station hadn’t shifted to a different altitude, according to data compiled by astrophysicist Jonathan McDowell.

The close encounters prompted the Chinese government to criticize SpaceX in a Dec. 6 memo to a United Nations committee that oversees operations in space.

China’s complaint could prompt global action on managing congestion in space.

“Originally, when I saw this Chinese U.N. document, I went, ‘That’s a bit rich of the Chinese, given the space debris they’ve generated,’ ” said McDowell, an astronomer at the Center for Astrophysics, which is operated by Harvard University and the Smithsonian Institution. “But I think it’s a good sign.”

By flagging the issue to the U.N. panel, China could spur the international community to update a treaty rooted in the Cold War, McDowell said.

He counts more than 4,800 commercial satellites in operation, about double the total from five years ago, along with a debris field of about 19,000 objects large enough to be tracked on radar.

The International Space Station, in which the United States is a partner, has faced close calls of its own, ducking debris fields created from antisatellite weapons tests by Russia in November and China in 2007.