[ILLEGIBLE], January [ILLEGIBLE]Date unknown

On June 28, 1952, at 6:00 p.m. Central time, a man on the shore of Lake Koshkonong in Wisconsin, about five miles southwest of Fort Atkinson and 32 miles southeast of Madison, reported one silver-white sphere. He saw it about the same time as a jet fighter he believed was an F-80 or P-80, flying southwest at about 6,000 feet. The sphere was much higher and on the same heading.

The observer said the object was about half the wingspan of the jet. It turned 180 degrees, becoming an ellipse during the turn and round again, then took a northeast course and seemed to climb as it disappeared. Its speed was estimated at about five times that of the jet. There was no sound other than the jet, and no trail or exhaust. It was in sight about ten seconds.

Weather was clear with bright sun and 15 miles visibility. A temperature inversion was called very unlikely. A later message reported that about 5,000 small balloons were released in the Chicago area on June 28, and that no balloon releases were known near the lake. The observer was a private citizen whose reliability was listed as unknown.