Unidentified flying object (UFO), History, Sightings, & Facts

Unidentified flying object (UFO), any aerial object or optical phenomenon not readily identifiable to the observer. UFOs became a major subject of interest following the development of rocketry after World War II and were thought by some researchers to be intelligent extraterrestrial life visiting Earth.

What exactly are UFOs?, Articles

History's Most Infamous UFO Sightings of the Modern Era

How the U.S. Air Force Investigated UFOs During the Cold War

Unidentified flying object (UFO), History, Sightings, & Facts

See Something, Say Something”: UFO Reporting Requirements, Office of Military Government for Bavaria, Germany May 1948 – The Text Message

FBI — The FBI and UFOs

No evidence of space aliens so far in the Pentagon's UFO deep-dive

UFO Sightings in Arkansas

Pentagon report says UFOs can't be explained, and this admission is a big deal

Piedmont, Mo.: Future UFO capital of Missouri?

U.F.O.s: Why the Truth Has Not Always Been Out There - The New York Times

NASA's UFO Study Isn't Really Looking for Space Aliens

Pentagon now reports about 400 UFO encounters: 'We want to know what's out there' - ABC News