The Kelly–Hopkinsville encounter is a claimed close encounter with extraterrestrial beings that occurred near the communities of Kelly and Hopkinsville in Christian County, Kentucky, United States during the night and early morning of August 21–22, 1955. UFOlogists regard it as one of the most significant and well-documented cases in the history of UFO incidents, while skeptics maintain there was no actual physical evidence that the encounter ever took place and the reports were due to "the effects of excitement" and misidentification of natural phenomena such as meteors and owls. The alleged encounter was officially classified as a hoax in the Project Blue Book files by the United States Air Force.