Beijing ? Scientists have concluded that a Chinese missile test in January that smashed an aging weather satellite was the messiest space event ever, adding more than 1,500 big scraps of debris to a junkyard that’s orbiting the Earth.

They said it may only be a matter of time before a weather, communications or other satellite – or the manned International Space Station – slams into space rubbish.

The debris travels through space around 17,400 mph, 10 times faster than a bullet from a high-powered rifle and 100 times faster than a race car. A millimeter-sized orbiting fleck of aluminum can have the kinetic energy of a bullet against a billion-dollar satellite, said Fernand Alby, chief of debris monitoring at the French space agency, CNES.