Pinterest Facebook Twitter Email UFO Fleet 00:39 An eyewitness is left with questions after he spots UFOs over Philadelphia. Related Videos UFO Clusters 00:43 UFO Secrets 00:59 UFO Installation 02:59 UFO Paintings 00:50 Ocean UFO 00:17 UFO Investigations 00:30 Denver's UFO 01:51 UK UFO 00:50 More Videos Mass UFO Sightings 42:00 UFOs Over DC? 02:47 The O'Fallon UFO 02:18 UFO Medical Exam 02:28 The UFO Car 03:02 Holy City UFO 00:33 UFO Central in Colorado 03:15 UFO Abducts Lumber Worker 02:45 Seismic Activity or UFOs? 01:58 Seven-Pound Seafood UFO 00:53 Don Explains: Roswell UFO 00:30 UFO Captured on Film? 03:19 Pentagon UFO and More 39:01 UFO Crash Site Metal 00:49 Martha's Vineyard, JFK & UFOs 01:25 A Deadly UFO Chase 02:40 We Recommend 5 Famous UFO Sightings Across the World 12 Best Destinations for UFO Fans 12 Photos US Fleet Week Events Alien Endgame Examines the Extraterrestrial Threats to Our Planet in a New Special on discovery+ Ho-Ho-UFO: Is That Santa’s Sleigh Or A Flying Saucer In The Sky? Discovery+ Greenlights Season Two of UFO Witness to Investigate Official Government Documents and Remarkable New Video Evidence Coming to Light