Unidentified flying object

A UFO (Unidentified Flying Object) is an object in the sky which cannot be identified.

Photo from New Jersey, USA

Identified flying objects (IFOs)

Studies estimate that 50-90% of all reported UFO sightings are identified later. Most are natural or man-made objects that looked strange. 80-90% of UFOs are identified as one of three things:

1. astronomical causes (for example: planets, stars, or meteors)
2. aircraft
3. balloons (including weather balloons)

New term

Since the 2020s, people have come up with the following terminology:

• Unidentified Aerial Phenomena
• Unidentified Anomalous Phenomena

Therefore, it is common to hear "UFO" and "UAP" while listening to people talk about this topic.^[1][2]

References

• Allan Hendry, The UFO Handbook: A Guide to Investigating, Evaluating, and Reporting UFO Sightings, 1979, Doubleday & Co., ISBN 0-385-14348-6

Other websites

• Wikinews - UFO Archive
• CIA educational summary on UFO Archived 2007-05-09 at the Wayback Machine (working link or what? Maybe it should be used this link Archived 2019-10-01 at the Wayback Machine instead?)
• NASA Institute for Advanced Concepts
• BBC article on Mexican Air-force videotape
• NASA UFO Hacker Video Interview Archived 2007-11-13 at the Wayback Machine
• Popularmechanics Article - When UFOs Arrive: February 2004 Cover Story Archived 2007-09-27 at the Wayback Machine