Some fear an orbital debris chain reaction (sort of like fission).CaptainBeowulf wrote:Space junk becomes a problem. If you have people putting up lots of cheap stuff that breaks down the whole time, you get to the point where you'll lose track of it, and where it interferes with most launch trajectories. There's also the danger of two large satellites colliding and turning into a cloud of thousands of bits of shrapnel, some of which can then cause other spacecraft to disintegrate, magnifying the problem. Some people I've talked to who've had jobs involving tracking objects in orbit etc. think that there's already a dangerous amount of junk up there.
http://www.denverpost.com/headlines/ci_5165772