Project 10073 Record Card — Sighting in Grand Junction, Colorado, 28 September 1960

This document collection details an unidentified aerial phenomenon (UAP) sighting reported on 28 September 1960, involving observers in Grand Junction, Colorado, Farmington, New Mexico, and Eagle, Colorado. The primary report describes a square light within a round circle, displaying red, green, and white flashing lights. The object was reported to be stationary for approximately 20 minutes before moving southwest. Witnesses utilized a theodolite to estimate the object's altitude at 37.5 miles. The report was processed by the Air Technical Intelligence Center (ATIC) under Project 10073. Following an investigation, which included obtaining weather data from the Air Weather Service, ATIC concluded that the sighting was not an anomalous craft but rather an atmospheric phenomenon. Specifically, investigators identified a temperature inversion present on the date of the sighting. They argued that this inversion caused light refraction, leading to 'looming mirages' and geometric inconsistencies in the triangulation performed by the witnesses. The official assessment states that the inversion was responsible for the misidentification of common objects and errors in determining their actual location. The file includes internal military communications, a record card, and correspondence regarding the transmission of weather records to support the analysis.