The famous "One small step for man" phrase that Neil Armstrong uttered after first stepping onto the Moon was long thought to have been decided upon after the spacecraft's landing. A new interview with Armstrong’s brother, however, suggests that the astronaut scripted the line months ahead of the mission. In the BBC biopic Neil Armstrong – First Man on the Moon, Dean Armstrong reveals that Neil asked him what he thought of the quote while playing a game of Risk before leaving for Cape Canaveral. Armstrong’s brother also confirms that the astronaut had originally written "for a man" despite the omission of the "a" from the line's transmission.

The interview runs counter to what Armstrong says in his 2005 biography, clarifying that the quote evolved over the course of the flight mission. But as Dr Christopher Riley — the director of the BBC program — points out, Armstrong had a good reason for doing so: "It was probably easier to just say that he’d thought it up after landing, thus dodging the issue of where the words came from, and who maybe suggested them, or influenced him."