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Unidentified Flying Object
Unidentified Flying Object (UFO) is any object or light, reportedly sighted in the sky, that cannot be immediately explained by the observer. Sightings of unusual flying objects date back to ancient times, but UFOs (sometimes called flying saucers) became widely discussed only after the first widely publicized U. S sighting in 1947. Many thousands of such observations have since been reported worldwide.
At least 90 percent of UFO sightings can be identified as conventional objects, although time—consuming investigations are often necessary for such identification. The objects most often mistaken for UFOs are bright planets and stars, aircraft, birds, balloons, kites, aorial flares, peculiar clouds, meteors, and satellites. The remaining sightings most likely can be attributed to other mistaken sightings or to inaccurate reporting, tricks, or delusions, although to disprove all claims made about UFOs is impo
A. It was the first evidence showing the existence of intelligent life outside Earth.
B. It helped to explain some sightings of unusual events occurring in the sky.
C. It aroused widespread interest in unidentified flying objects in the sky.
D. It started off a new era of flying saucers in the United States.
