Have you ever thought about the problem of space debris? Even if some of the debris in orbit eventually burns up in the atmosphere, there must still be a lot out there, orbiting. I'm surprised we don't hear more stories about collisions with debris, seeing as how even a tiny shard or piece of dust could creaste colossal damage at high speeds. There've been some collisions with satellites, and just imagine how many individual shards and debris that creates. If a floating piece of debris hits a vehicle or a bigger piece of debris, this could create even more, leading to a chain reaction effect.
I think this should be a pretty big goal for space agencies or humans in general about space; in about fifty years of space, we've created millions of pieces of space debris, not to mention the natural space dust already out there. We should at least try to figure out a way to reduce the amount or diverting it... Imagine what would happen if more and more crashes occurred in Earth's orbit, and it became virtually impossible to go out into space without getting hit and even furthering the amount of debris...
