Hynek's astronomical review of Project Sign cases

When
First page of the Project Sign report
The Project Sign report, which included Hynek's astronomical review of cases US Air Force, Public domain, via Wikimedia Commons

Astronomer J. Allen Hynek reviewed the 237 reports gathered by the Air Force's Project Sign. His final report attributed about a third to astronomical causes such as planets and meteors, about a third more to balloons, rockets, flares or birds, and left about a fifth unidentified.

Sources

  1. PressMeet J. Allen Hynek, the Astronomer Who First Classified UFO 'Close Encounters' (opens in a new tab)History.com (Greg Daugherty) / 2018-11-19

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