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Guest Editorial

UFO Defined
by Philip A. Stahl
from the March, 2003 issue of the MENSA Bulletin,
used by permission

In the January issue of the MENSA Bulletin, Donna Shirley argues there've been no recent UFO sightings because "the most likely reason is that UFOs do not exist." In fact,the problem in her argument is being unaware of the operational definition of "UFO" given by the late J. Allen Hynek of Northwestern University. Hynek, an astrophysicist, devoted many years to the scientific study of the UFO phenomenon. His definition reads as follows:

"A UFO is the reported perception of an object or light - seen in the sky or upon the land, the appearance, trajectory, and general dynamic and luminous behavior of which do not suggest a logical, conventional explanation and which is not only mystifying to the original percipients but remains unidentified after close scrutiny of all available evidence by persons who are technically capable of making a common sense identification if one were possible."

The preceding leaves the UFO unidentified so the definition doesn't descend to the most popular, debased usage, i.e. "UFO" equals "alien spacecraft." This precision then avoids the usual conflation and lack of clarity. Given Hynek's definition, the logical explanation for why fewer UFOs are being reported is that more people are better educated to discern what they are seeing in the night skies. In other words, they no longer mistake Venus or Jupiter at their brightest or the occasional artificial satellite for a UFO.

By the way, a consistent core of 3 percent of sightings remains unidentified.

Disclaimer: The opinions expressed in editorials are those of the individual authors, and do not necessarily reflect the position of The SETI League, Inc., its Trustees, officers, Advisory Board, members, donors, or commercial sponsors.

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