Space Junk, Long Feared, Is Now an Imminent Threat

Space Junk, Long Feared, Is Now an Imminent Threat

In March, a Chinese military satellite appeared to spontaneously disintegrate in orbit, leaving a trail of debris high above the Earth. If China knew anything, it wasn’t saying. Did the propulsion system explode? Was there a collision with some of the space junk that’s accumulating in orbit? Or did something a bit more conspiratorial happen? The mystery persisted until last month, when an astronomer at the Center for Astrophysics announced the answer. Yunhai 1-02, as the satellite is known, collided with a piece of junk leftover from a 1996 Russian rocket launch.It was the first major smash-up in Earth orbit since 2009. It won’t be the last. Thanks to cost-saving advances in rocket and satellite technologies, more countries and companies are preparing to launch more stuff into orbit than ever before. As they do, the risk of collisions will only rise. The good news is that space junk is one of the rare problems where geopolitical adversaries and corporate rivals should find common cause. At least, that’s the hope.Scientists and policy makers have been worrying about space junk — the dead and unwanted craft left behind in the finite space of Earth orbit — for decades. A paper published in 1978