Eugene A. Cernan (1934–2017), known as Gene, was an American naval aviator and NASA astronaut who flew Gemini 9A and Apollo 10 and commanded Apollo 17, becoming in December 1972 the last person to walk on the Moon. His place in UAP discussion rests on two things: lights and fragments his crew described during the flight, whose records the Department of War re-released in 2026, and a secondhand story circulated that year claiming aliens had warned him away from the Moon.

Born in Chicago on March 14, 1934, Cernan earned an electrical engineering degree from Purdue University in 1956 and was commissioned in the Navy through its reserve officer program. He flew jets as a naval aviator, completed a master's degree in aeronautical engineering at the Naval Postgraduate School and was selected by NASA in October 1963 in its third group of astronauts. On Gemini 9A in June 1966 he made the second American spacewalk, which was cut short when he became exhausted without proper restraints. In May 1969 he was lunar module pilot of Apollo 10, the dress rehearsal for the first landing, flying the lunar module Snoopy to less than ten miles above the surface.

Apollo 17 flew from December 7 to 19, 1972, with command module pilot Ronald Evans and lunar module pilot Harrison Schmitt. Cernan and Schmitt landed in the Taurus-Littrow valley and spent three days on the surface. Before climbing back aboard, Cernan said, "We leave as we came and, God willing, as we shall return, with peace and hope for all mankind." He retired from the Navy as a captain and from NASA in 1976, worked in the energy industry and founded an aerospace consulting firm in 1981. His memoir, The Last Man on the Moon, appeared in 1999 and became a 2014 documentary. He passed away in Houston on January 16, 2017, at 82.

The mission transcript in the first PURSUE release of May 2026, and an audio excerpt added two weeks later, show the crew identifying most of what they saw themselves. In the audio, from launch day, the three men describe jagged, angular "particles" or "fragments" drifting near the spacecraft and the spent rocket stage, which they guessed were paint or ice chips. Cernan also reported intense flashes, comparing one to a train's headlight, and a distant rotating object; NASA later linked the astronauts' light flashes to cosmic rays passing through the eye.

On May 9, 2026, podcaster Jesse Michels posted a clip of Japanese writer Takano Jousen, whom he called a NASA historian close to Cernan, saying Cernan had told him the crew received a message from aliens never to return to the Moon, and that this was why Apollo ended with 17. The clip drew more than a million views. IBTimes UK reported that the story does not appear in the government documents and that Cernan never made such a claim on the record, while NASA had canceled its last planned landings during 1970, amid budget cuts, before Apollo 17 flew. Cernan's own public message ran the other way: he spent his later years urging a return to the Moon, and his family asked that he not remain the last person to have walked there.