The trash that can take out a satellite

The five astronauts and two cosmonauts on the International Space Station were ordered to suit up and take refuge in their capsules for fear their spaceship might be struck by flying debris. Russia had deliberately destroyed one of its own satellites with a missile, producing a cloud of wreckage that threatened the orbiting outpost. “It’s a crazy way to start a mission,” Nasa told its sheltering crew, who had arrived only days beforehand.

The incident in November last year revealed how hairy Earth’s orbit has become, and it wasn’t a one-off. Two weeks later, mission controllers received another alert that the ISS might be hit by more debris. This time, Nasa delayed a planned spacewalk amid concerns that astronauts could be in danger if they went outside. Before the week was out, yet another warning came in, this one forcing