In mid 1947, a crash of a military Air Force surveillance balloon at a ranch near Roswell, New Mexico gave rise to claims alleging the crash was of an extraterrestrial spaceship.After an initial spike of interest, the military reported that the crash was merely of a conventional weather balloonInterest subsequently waned until the late 1970s when ufologists began promulgating a variety of increasingly elaborate conspiracy theories claiming that one or more alien spacecraft had crash-landed and that the extraterrestrial occupants had been recovered by the military who then engaged in a cover-up.Tap to save Roswell's Alien!