Yuma City, Ariz., February 1953February 1953

On February 4, 1953, a weather observer at Yuma County Municipal Airport in Arizona was using a theodolite (an optical instrument for measuring angles) to track a lost weather balloon when he spotted two solid white objects in the sky.

At 1:50 p.m., the observer noticed the first object ascending straight up, then leveling off. About twenty seconds later, a second object appeared and flew near the first one in a formation pattern. The observer described both objects as nearly round, pure white in color, and roughly one minute of arc in size (a very small angular measurement through the theodolite lens). Each object appeared to have a thin white mist around its edges. The two objects remained visible for five minutes as the observer tracked them through the instrument. Both objects moved westward, with the second one staying lower and behind the first. They finally disappeared behind cirrus clouds (thin, feathery clouds at about 25,000 feet elevation).

The observer noted something unusual: the objects rose much faster than any balloon he had encountered during his seventeen years tracking weather balloons for the U.S. Weather Bureau. He also held a private pilot's license and was familiar with aircraft. More striking still, the objects moved against the prevailing westerly winds. There was no glimmer or reflection from the sun on either object.

The Air Force investigation concluded that the objects could not have been balloons, given their rapid ascent and movement against the wind. Aircraft in the area were ruled out because the observer was aware of them and could distinguish them from what he saw. The file states that ATIC (the Air Technical Intelligence Center) was unable to find an answer to the sighting. The case was evaluated as unknown.

The full case file is reproduced below as held by the National Archives across 25 pages of scanned documents.