Abstract
Changes in tectonic strain within the earth's crust have been hypothesized to be the primary energetic source for most documented UFO (unidentified flying object) events. Multiple regression analyses indicate that at least 50% of the variance in UFO report measures can be accommodated by optimal solar-seismic variables. Equations for the central U.S.A. accurately predicted the occurrence of UFO-report episodes after the years from which they were generated and indicate the occurrence of UFO-like reports long before the year 1947. However the labels applied to these phenomena may have changed from generation to generation.