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Aliens & UFOs

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.

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History of the Roswell UFO Incident

The history of the Roswell UFO incident has a long, complicated legacy of truth and conspiracy. From the crash site to the recovered alien bodies, there is a lot of speculation -- how much is believable? Learn more history of the Roswell UFO incident.


The Oz Factor

The Oz Factor is a sensation that UFO witnesses experience. Learn where the term "Oz Factor" came from, and what the experience is like. See more »

Space Animals

John Philip Bessor originally theorized that UFOs could be a form of space animal. Learn more about space animals and the UFO critter theory. See more »

Explaining UFOs

Both skeptics and believers spend time researching UFO reports and explaining UFOs as natural or supernatural events. Read more about explaining UFOs. See more »

UFOs & Government Secrecy

Does the government maintain secret contact with extraterrestrials? Learn about theories of UFOs and government secrecy in the CIA and the NSA. See more »

UFO Theory

UFO theories vary as widely in their credibility as in their imagination. Learn about theories of UFOs, aliens, spaceships, and the government. See more »

UFOs and the Government

Project Sign was the first major government UFO investigation project. Read how Project Sign began and the history of UFOs and the U.S. government. See more »

UFO History

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In July 1947, unusual debris was found in Roswell, N.M. The Army said they had a crashed disc, and later rescinded.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 »