Recently US and Russian satellites collided in space. Supposedly it made a huge debris field which is now putting other satellites at risk. The US government tracks all space debris larger than a football, but they missed that this would happen.
The European Space Operations Centre has put together some images showing just how much stuff is orbiting around earth. In the picture below all the little whitish blotches and the big smudge circling close to earth all represent objects floating in space:
Between the launch of Sputnik on 4 October 1957 and 1 January 2008, approximately 4600 launches have placed some 6000 satellites into orbit; about 400 are now traveling beyond Earth on interplanetary trajectories, but of the remaining 5600 only about 800 satellites are operational… Space debris comprise the ever-increasing amount of inactive space hardware in orbit around the Earth as well as fragments of spacecraft that have broken up, exploded or otherwise become abandoned.
A closer picture:
A view of the polar orbit:
These are amazing pictures and after seeing these it is surprising there are not more satellite collisions.
You can read a longer article about this here.