UFO Sightings
Frequency Spectrum
Every UFO sighting in the data is compared to all
subsequent listings, regardless of location.
A special array is incremented for each interval, in weeks
elapsed between sightings.
Counts for each interval show as white dots. The violet curve is a running average of these counts. As expected, time intervals between major waves show as peaks in this curve, and are marked with a green carat ^ sign.
Intervals between approaches to Venus, Mars and Jupiter are marked with colored letters V, M and P.
Only Mars, about 110 weeks, corresponds to a major peak. A 'close approach' occurs when Earth and some planet reach the same sidereal longitude, as close as they can physically get.
Special thanks to Jacques Vallee for the algorithm.