In January more than 100 communications satellites burned up in Earth’s atmosphere, vaporising as they crashed towards the planet at about eight kilometres a second. These spectacular exits are intentional, meant to prevent satellites from clogging up orbital real estate or plummeting to the surface in an out-of-control manner. Three years ago the Federal Communications Commission (FCC), an American agency that approves communications-satellite applications, ordered that all such satellites had to fall out of orbit after five years to reduce space debris. Similar regulations apply elsewhere.