Those in the space industry call it 'orbital debris', to the rest of us it's 'space junk' and new computer generated images show how it's gradually beginning to fill the space around our planet.
Everything which is launched from Earth now has to negotiate a path through the swirling mass of junk, some moving at thousands of miles per hour. Even the smallest piece of junk moving at 10,000 mph could dent the International Space Station
The danger exists for astronauts too, they could be killed instantly by a stray nut or bolt in orbit. The junk consists of derelict spacecraft, old satellites, bits of metal, lost tools, human waste and solid rocket fuel. NASA tracks much of it.