Do Aliens & UFOs exist? Has man been visited by other races from other worlds? Explore the fascinating evidence for and against the existence of extraterrestrials.
Modern UFO history began with the 1947 UFO sighting by pilot Kenneth Arnold. Learn the history of UFOs from ancient times to the mid-20th century. See more »
How Area 51 Works
Area 51 is the most famous secret military installation in the world. Learn all about Area 51 and find out why Area 51 is such a heavily guarded secret. See more »
July 7, 1947: UFO Crashes in Roswell, N.M.
In July 1947, unusual debris was found in Roswell, N.M. The Army said they had a crashed disc, and later rescinded. Learn about the Roswell incident. See more »
How UFOs Work
UFOs, first defined by the Air Force as any unidentified flying object, have since become synonymous with alien spacecraft. Learn about UFOs and UFO sightings. See more »
How Aliens Work
Alien life forms would probably differ from those on Earth but still adhere to certain principles. Learn about astrobiology and the search for alien life forms. See more »
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