Spherical UFO seen in Oregon in 1954

Summary

A witness at a dairy in Oregon, USA, reported a bright silver spherical object in December 1954. The object was about 40 feet in diameter, emitted thin black smoke, and was spinning rapidly. It was observed for 45 minutes, with periodic jet-like sounds. Although the report mentions a possible balloon explanation, the data was insufficient for a conclusive evaluation. The observer used binoculars, a rifle scope, and a surveyor's transit, suggesting a detailed observation. The object's movement, which seemed to stop and then accelerate, adds mystery to the case.