And they would be wrong. Niel Armstrong didn’t seem to carry a nickname; he was an aviator in the US Navy, who usually end up with callsigns, but I’m struggling to find what his was. Google “assistant” is hallucinating; it’s saying that Neil Armstrong’s navy callsign was “WARL” and links to a Wikipedia page about the oceanographic research ship RV Neil Armstrong(AGOR-27) whose maritime radio callsign is WARL. I know of no personal nickname or callsign of his.

Aldrin, on the other hand…I’m just now learning this. I assumed he got the nickname Buzz as a USAF pilot callsign, but no. His sister Faye mispronounced “brother” as “buzzer” which was shortened to “Buzz.” And he legally changed his name to “Buzz Aldrin” in 1988. It was still a nickname during the Apollo program.