Pulsating blue UFO over Arizona and New Mexico

Summary

An unidentified object was observed in September 1953 over Arizona, Texas, and New Mexico. Both military pilots and civilian observers reported seeing an object emitting a pulsating blue flame, similar to a jet engine. It was estimated to be traveling at over 500 mph at an altitude of between 18,000 and 20,000 feet. The object was seen for a few seconds, and while some witnesses described it as bright and white, others compared it to a flash in the cloud. Despite multiple sightings, no physical evidence or photographs were found. The official conclusion was that the phenomenon had an astronomical origin, although witness descriptions varied slightly. The case remains a mystery in UFO history.