Project Blue Book Case File
PLATTEVILLE, [ILLEGIBLE]Date unknown
Summary
# Platteville, Wisconsin UFO Sighting
On June 28, 1952, a civilian observer near Platteville, Wisconsin reported seeing an unusual object in the sky. The witness, whose background and reliability were unknown at the time, described a round or teardrop-shaped object about the size of a dime held at arm's length. The object was pale green in color, left no trail or exhaust, and moved at tremendous speed in a smooth arc toward the north-northwest. The entire sighting lasted roughly two seconds.
The observer was positioned on the ground at coordinates near Platteville, looking northeast into the sky at an angle of approximately 35 degrees above the horizon. Weather conditions at the time were clear, though lightning was visible in the western sky from an approaching cold front. The Air Force investigators found no meteorological or other solar disturbances that might have explained the sighting, and no physical evidence was recovered. Because the report reached investigators with a significant delay, no immediate interception or identification action was possible.
The file also contains unrelated UFO reports from Japan and other U.S. locations from the same period in June and July 1952. The Platteville case itself concludes with no definitive explanation. The full case file is reproduced below as held by the National Archives across 34 pages.
Reported location
PLATTEVILLE, [ILLEGIBLE]
Date of incident
Date unknown
State / country
? / XX
Page count
34 scanned pages
USAF evaluation
unknown
Microfilm
T1206, Roll 10