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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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UFOs & Government Secrecy

Does the government maintain secret contact with extraterrestrials? How long have they been communicating? Learn about theories of UFOs and government secrecy in the CIA and the NSA.


Hollow Earth Theory

Hollow earth theory was the brainchild of John Cleves Symmes, who sought to explore Earth's center, where UFOs supposedly come flying in and out. Read why some believe UFOs live inside the Earth. See more »

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. These organisms may even be carnivorous. 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, whether meteor or balloon or optical allusion or good old-fashioned mystery. Read more about explaining UFOs. See more »

UFOs & Government Secrecy

Does the government maintain secret contact with extraterrestrials? How long have they been communicating? Learn about theories of UFOs and government secrecy in the CIA and the NSA. See more »

UFO Theory

Since humans have observed strange phenomena, they have tried to explain them. 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

In the early 20th century, wherever there were "flying saucers," there was also ridicule, dished out to anyone courageous or foolish enough to defy the orthodoxy. How involved were the government researchers in UFO research--and what did they find? See more »

UFO History

Modern UFO history began with the 1947 UFO sighting by pilot Kenneth Arnold. But the roots of UFO stories stretch back to ancient and medieval days. Learn about the history of UFOs and strange phenomena from ancient times to the mid-20th century. See more »

How Area 51 Works

Less than 100 miles from Las Vegas, is the most famous secret military installation on the planet: Area 51. For decades, the U.S. government refused to acknowledge it existed. But now, the secret is out. See more »

July 7, 1947: UFO Crashes in Roswell, N.M.

In July, 1947, unusual debris was found in Roswell, N.M. The U.S. Army stated they had received a crashed disc, only to rescind it hours later. Learn more about the Roswell,N.M. UFO crash. See more »