Space junk a 'serious issue'
2 September 2011 Last updated at 12:15 BST
Scientists in the US have warned Nasa that the amount of so-called space junk orbiting Earth is at tipping point.
The National Research Council says the debris could cause fatal leaks in spaceships or destroy valuable satellites.
It calls for international regulations to limit the junk and more research into the possible use of launching large magnetic nets or giant umbrellas.
Deputy Executive Secretary of the Royal Astronomical Society, Dr Robert Massey said: "The problem is there are lots and lots of tiny fragments that are almost impossible to detect.
"It is a serious issue not just for astronauts but for all the commercial satellites that we're so used to and we really depend on."