UFO
A UFO, or unidentified flying object, is any apparent aerial object or phenomenon observed in the sky whose nature, origin, or identity cannot be immediately or readily explained by the observer. The equivalents submerged in water are called unidentified submerged (submarine) objects (USO).
History
The term was formally introduced by the U.S. Air Force in the early 1950s (replacing the more sensational “flying saucer”) to describe sightings that do not conform to known aircraft, missiles, or familiar phenomena at the time of observation. By definition, a UFO is simply “unidentified”—it carries no inherent implication of extraterrestrial origin, advanced technology, or anything extraordinary. Most reported UFOs are later explained as conventional aircraft, weather balloons, drones, astronomical events, optical illusions, or hoaxes once investigated. The term has largely been superseded in official and scientific contexts by the more neutral UAP (Unidentified Aerial Phenomena or Unidentified Anomalous Phenomena) to reduce cultural baggage. In short: UFO = something seen in the air that hasn’t been identified yet. Nothing more, nothing less.
