UFO

An unidentified flying object (UFO) is an aerial phenomenon that cannot be immediately identified or explained. This is primarily a Type 0 phenomenon and the majority of sightings can be explained. However a Type I civilization realizes that some of them had actually been monitoring technology or actual visits from extraterrestrials.

Type 0 explanations

 * astronomical objects: stars; bolides; planets; the Moon
 * aircraft; aerial advertising; rocket launches, artificial satellites; kites; drones
 * balloons
 * atmospheric objects: birds; clouds; flares
 * other phenomena: mirages; ball lightning; searchlights
 * psychological effects: psychosis; suggestibility; mass psychogenesis; optical illusions; hallucinations
 * hoaxes

UFOs are commonly seen as flying saucers or flying craft having disc or saucer-shaped bodies.

Because of the inclination from governments to cover up a potential alien threat, UFOs enter the mainstream culture of Type 0 societies but are passed off as conspiracy theories due to the lack of sufficient proof e.g. Area 51 and Roswell.

News

 * In June 2021, U.S. Defense and intelligence officials released the Pentagon UFO Report on what they know about a series of unidentified flying objects that have been seen by American military pilots.
 * Michio Kaku discussing with CNN about the United States hosting the first public hearing on the subject of UFOs in decades, and declassifying some related findings.