Project 10073 Record Cards — Denver, Colorado, September 1956

This document consists of two Project 10073 record cards documenting civilian sightings of unidentified aerial phenomena in Denver, Colorado, in early September 1956. The first incident occurred on September 1, 1956, at 0310Z. A civilian observer reported a single red object that changed shape from oblong to square and emitted a very bright light. The object was observed visually and through binoculars for one hour and ten minutes, moving from the West to the Northwest. The official conclusion for this event was that it was likely caused by an astronomical body. The second incident occurred on September 2, 1956, at 0500Z. A civilian observer reported a single shiny, light green, elongated object, estimated to be the size of a large airplane. The object was observed with a green vapor trail, streaking downward at a very high rate of speed from North to South before vanishing in the sky. The observation lasted approximately thirty seconds. Following the receipt of this report via phone, an ATIC Form 164 was sent to the observer. Analysis of the returned form led investigators to conclude that the sighting was caused by a meteor. Both records note that there was no further report in the file.