How many UFO sightings have there been?
In 1992, several professors at MIT, the prestigious Massachusetts Institute of Technology, held a conference at the university on one aspect of the UFO phenomenon, the alien abduction experience. Speakers were carefully selected by a committee of highly respected university professors. Some of them had studied a considerable number of cases: Randles, 200; Harder, whose PhD is in physics, 300 cases; Hopkins, more than 500; and Ann Druffel, 2,000 cases in 35 years.
By summarizing their data, could we obtain an idea of the total number of sighting reports investigated?
In 1992, Jacques Vallée, a French astrophysicist now residing in California, estimated that over 100,000 such reports existed. This figure can be substantiated by data from a study of several thousand reports made by Gilda Moura (5). This study concluded that 11% of them occurred in the United States. A very incomplete survey taken in the U.S. shows that there were 8,000 cases up to 1994. That makes 72,000 cases worldwide, an unrealistically low number, since it is only based upon a partial count, which would be consistent with the number of over 100,000 indicated by Vallée, one of the leading experts in this field.
As most of these sighting reports have been recorded since the 1960s, this means that 3,000 new reports are being investigated every year. We will thus obtain some 130,000 valid sightings of varying quality by the beginning of the 3rd millennium.
Several sets of data can be used to make a rough estimate, and to cross-check the various figures. The average number of sightings is huge: in developed countries, 8 people out of every 1,000 claim to have seen a UFO before 1970, and 6 out of every 1,000 claim that they were abducted between 1970 and 2000.