UFO near collision with plane in Iowa 1957

Summary

An aircraft nearly collided with a large white object, the size of a basketball, at 7,000 feet altitude. The pilot described it as a solid object with bright light. The sighting occurred about 10 miles south of Ottumwa, Iowa. Although a weather balloon from the Des Moines station was considered a possible explanation, no definitive conclusion was reached. Wind direction and location align with the balloon station, suggesting a plausible but unconfirmed explanation.

The official report includes weather data and a detailed description of the object. The pilot did not report any unusual actions and did not attempt to follow the object, which disappeared from the area in five to six minutes. Despite a clear visual description, the object could not be identified with certainty, and various possibilities were considered, from balloons to astronomical objects.