Project 10073 Record Card — Green Bay, Wisconsin, 17 October 1957

This document consists of a Project 10073 record card and associated teletype correspondence regarding an unidentified aerial phenomenon reported in Green Bay, Wisconsin, on October 17, 1957. Three witnesses—a school teacher, a clerk, and a city worker—observed a large, round object with a white glow for approximately 40 minutes. The object was described as traveling very slowly from north to south before fading from view. The sighting occurred at dusk, specifically noted as 18:12 hours (6:12 PM). The investigation determined that the object was a weather balloon. A check of weather schedules confirmed that a radio balloon with a light attached had been launched from the local airport one hour prior to the sighting. The balloon was reported to rise and descend very slowly, which matched the witnesses' observations. The final assessment concluded that the object was a balloon, noting that the appearance was consistent with typical characteristics of a balloon observed at dusk.