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Hynek Classification System

J. Allen Hynek

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Summary: The system used to categorize the various types of UFO sightings invented by Dr J. Allen Hynek and adopted by many UFO researchers as the standard for classification. The system was later enhanced by Jacques Vallee.

J. Allen Hynek , Ph.D.

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HYNEK CLASSIFICATION SYSTEM

A system used to categorize the various types of UFO sightings invented by Dr J. Allen Hynek. The categories are as follows...

NOCTURNAL LIGHT
Any anomalous light(s) seen in the night sky whose description rules out the possibilities of aircraft lights, stars, meteors and the like.
DAYLIGHT DISK UFOs
seen in the distant daytime sky. The UFOs classed in this category can be other shapes as well, like cigars, eggs and ovals.
RADAR-VISUALS
Where UFOs are tracked on radar and can be seen at the place illustrated at the same time.

CLOSE ENCOUNTERS...

OF THE FIRST KIND (CEI)
A UFO in close proximity (within approx 500 feet) of the witness.
OF THE SECOND KIND (CEII)
A UFO that leaves markings on the ground, causes burns or paralysis to humans, frightens animals, interferes with car engines or TV and radio reception.
OF THE THIRD KIND (CEIII)
A CEI or CEII which have visible occupants.
There are also two more unofficial classes of Close Encounter...
OF THE FOURTH KIND (CEIV)
Abduction cases.
OF THE FIFTH KIND (CEV)
Communication occurs between a person and an alien.