UFO means Unidentified Flying Object and there are lots of them to see in the sky. But unidentified means you don't know what it is. It doesn't mean it's an alien spaceship. We'll travel to Roswell and see the place where some say there is an alien spaceship. We'll visit the large aircraft hangar where the wreckage was taken and ask whether the military found alien bodies inside a flying saucer. We'll meet the people who believe we are being visited by aliens and see equipment that scans the skies every night to catch anything that moves.