Sante Fe, N.M., September 1948 - Incident Number: 175September 1948

On September 23, 1948, an experienced pilot in downtown Santa Fe, New Mexico, spotted an unusual object in the sky while watching another aircraft. The object appeared brilliant white, perfectly round and flat when viewed from above, with no metallic sheen. Estimating it at roughly the size of a dime at arm's length and using a nearby radio tower for perspective, he judged it to be at an altitude of 30,000 feet. That would make the object approximately 100 to 150 feet in diameter.

The observer watched the object remain almost stationary for about 15 to 20 minutes. He reported seeing no sound, exhaust trail, or air turbulence. He drew the attention of a companion to the object, and both men went inside a building to conduct business. When they emerged several minutes later, the object was still roughly in the same spot in the sky.

A second witness interviewed in the case provided some conflicting details. He described the object as silvery and egg-shaped rather than perfectly round, and estimated it moved at speeds between 700 and 800 miles per hour. He also noted a bluish tint at the rear, which he thought might be exhaust. This observer believed the object traveled from northeast to southwest, while the first witness described it as moving in a semicircle from south to east and finally to northeast, though he acknowledged this could have been an optical illusion.

The investigation noted that weather conditions were clear on the day of the sighting, with excellent visibility extending 40 miles. Investigators checked local flight schedules for military, commercial, and private aircraft in the area but found no explanation. They also checked for weather balloons released by the Air Force, Navy, and Weather Bureau at the same time as the observation. A pilot balloon released from Albuquerque at the moment of sighting showed upper winds that could not have carried it to Santa Fe, ruling it out as a possible explanation.

The Air Force's investigative report on the case concluded that the object was "not a balloon." The file notes suggest disagreement among those examining the evidence, with some observers insisting the object could not have been a weather balloon given their familiarity with such equipment. The full case file, comprising 39 pages as held by the National Archives, is reproduced below.