The BEST seasons of NASA's Unexplained Files

Every season of NASA's Unexplained Files ever, ranked from best to worst by thousands of votes from fans of the show. The best seasons of NASA's Unexplained Files!

Strange flying objects have been caught on NASA's cameras and astronauts have reported seeing UFOs. Some of the odd shapes and lights can be identified; others remain a mystery. We'll reveal NASA footage and interview the astronauts and scientists.