We think of outer space as pretty empty, but that's not the case around planet Earth. There are millions of pieces of man-made debris floating around. This debris causes potential problems for astronauts, satellites, and other important pieces of equipment circling Earth. This fast-paced webcast will look at what's out there and how NASA keeps an eye on it, visit the full archived lesson with pictures and audience comments here.

Originally presented on March 18, 2015 | Explore the Support Materials below for the archived live-stream content with questions, comments, and images shared during the live event.