UFO sighting in 1957 over the United States and Canada

Summary

In August 1957, a UFO case was reported simultaneously in the United States and Canada. Observers, both civilian and military, described an object with characteristics resembling a comet's tail. The main source was a ground visual observation, and several data points suggest it could be Comet MRKOS, which was visible during that period. Although there were no photographs or radar involvement, testimonies align on aspects like direction and the object's behavior. A USAF officer, Stephen M. Flanagan, concluded it was likely Comet MRKOS, based on its trajectory and astronomical reports.