What was Neil Armstrong's middle name?

Neil Armstrong's middle name was Alden.

He was born Neil Alden Armstrong on August 5, 1930, in Ohio. “Alden” was part of his given name, not a nickname acquired during his aviation or NASA career. Armstrong later became an aerospace engineer, naval aviator, test pilot, and NASA astronaut.

Armstrong commanded Apollo 11, the first crewed mission to land on the Moon, and became the first person to step onto the lunar surface on July 20, 1969. Before Apollo 11, he had flown Gemini 8, where he and David Scott performed the first docking of two spacecraft in orbit.

A common mix-up is “Neil Alden Armstrong” being remembered as though Alden were a middle initial or a second surname. The names of his Apollo 11 crewmates can also cause confusion: Edwin “Buzz” Aldrin and Michael Collins were his fellow astronauts, but neither name is Armstrong's middle name.