Hynek's Close Encounters: A Classification Framework for Unexplained Aerial Phenomena and the UAP Shift

To the point

J. Allen Hynek created a distance- and interaction-based framework for unexplained aerial phenomena, classifying sightings from close visual encounters to occupants, abductions, and human-initiated contact, later extended with radar, trace cases, and the UFO-to-UAP shift.

How UFO Encounters Are Classified From CE1 to CE5
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How UFO Encounters Are Classified From CE1 to CE5

How investigators classify UFO encounters using the Close Encounter system and where skepticism applies.