San Juan, Puerto Rico, February 1960February 1960

On the evening of February 26, 1960, a geologist in San Juan, Puerto Rico saw a bright red object streak across the sky. The object was ball-shaped and about the size of a large pea held at arm's length. It had a yellowish-orange tinge and was visible for less than one second. As it disappeared, it left behind a contrail (a thin, wispy trail of smoke) that persisted for about ten minutes.

The observer, Reginald P. Briggs, was standing about three and three-quarters miles northwest of Isla Verde Airport when he spotted the object. He estimated it was moving in a nearly straight line across the sky, from east to west. The object seemed to intensify in brightness just before it vanished. Briggs was described in the official report as reliable and an experienced observer, being a geologist with the U.S. Geological Survey.

The Air Force investigation quickly picked up multiple corroborating reports. A Navy tower at nearby Roosevelt Roads saw a large ball of fire with a trailing plume of smoke that descended from about 20,000 feet to 15,000 feet. An aircraft at 35,000 feet reported seeing a ball of fire fall from 55,000 feet to 6,000 feet. An airline pilot saw a streak of blue-white fire moving northwest, which he suggested might have been a missile or satellite reentry. A controller at an airport tower also reported seeing a stationary ball of fire with red sparks trailing behind it. The USS Tringa, a Navy ship in Ponce Harbor, recorded a brilliant flash with trailing smoke at an estimated altitude of 39,000 feet.

The Air Force prepared two competing explanations. The initial preliminary analysis suggested the sighting could have been a reentry of a ballistic missile or satellite. However, the official evaluation concluded it was most likely a Navy surface unit conducting a night illumination training exercise involving pyrotechnic (fireworks-like) activities. The short duration of the sighting and uncertainty about the object's exact direction of movement made the Air Force cautious about its conclusions. A weather balloon was released from Isla Verde Airport shortly after the sighting, but investigators did not believe it could account for what was observed.

The full case file, comprising 10 pages as held by the National Archives, is reproduced below.