Over 6000 satellites have been launched since the dawn of the space age. Some of them have come back to earth or continued on into the depths of the universe, but the vast majority are still wandering around up there. Over 4500 are not operational – they’re just slowly breaking up and forming a dangerous obstacle course for current missions into space.

Sometimes space debris falls back to earth, and each time a new rocket is launched bits of it come down without even reaching orbit.

I’m not sure who took these pictures, but I found them here. They’re evocative images – maybe they’ll remind us to look up every once in a while.