Sky & aerial phenomena
Close encounter
A Hynek-style scale describing how near a witness came to an unexplained aerial event.
Close encounters (CE1–CE3 and later extensions) classify sightings by distance and interaction, from visual observation to claimed contact.
Using the scale is optional; clear distance and duration notes still matter if you do not use CE labels.
Also known as
Close encounter · close encounter · close encounters · CE1 · CE2 · CE3 · CE-1 · CE-2 · CE-3
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