Michael Collins, Command Module Pilot, Apollo 11

1969-07-31 / Translunar coast (approximately 1 day from the Moon) / unresolved

During the Apollo 11 Technical Crew Debriefing on July 31, 1969, Buzz Aldrin described three observations from the mission. Approximately one day from the Moon, the crew spotted an object of sizeable dimension that appeared L-shaped through the monocular and like a hollow cylinder through the sextant; ground control confirmed the S-IVB stage was 6,000 miles away, and the crew reached no conclusion about the object's size, range, or identity. Aldrin also reported recurring small flashes of light inside the darkened cabin, spaced roughly a minute apart, which he guessed were caused by some penetration of an object into the spacecraft.

Unidentified object of sizeable dimension observed approximately 1 day out from the Moon; appeared L-shaped or like an open suitcase through the monocular; appeared as a hollow cylinder or two connected rings when viewed through the sextant (possibly due to focus); tumbling motion observed; size and range could not be determined