Satellites Are Crowding Space, and It’s Time for a Cleanup Plan

Since the Soviet Union launched Sputnik in 1957, Earth’s atmosphere has become home to almost 5,000 orbiting spacecraft. Yet despite the growing traffic, there’s been only one documented collision between satellites, when an Iridium communications craft and a dead Russian Kosmos spysat crashed 500 miles above Siberia a decade ago.

The risks are increasing fast, though. In the coming decade, tens of thousands of new satellites are scheduled for launch as billionaires such as Elon Musk, Jeff Bezos, and Richard Branson plan constellations of craft offering internet from space. Worse, debris such as old rocket parts, out-of-service satellites, and bits of shrapnel—the Iridium-Kosmos crash created thousands of pieces that will litter the skies for decades—represent a growing threat.