Charlie Duke was the NASA Capcom during the Apollo 11 landing. The Capcom (capsule communicator) is the sole contact between NASA mission control and the mission crew in space.
Only seconds away from depleting their fuel, Neil Armstrong and Buzz Aldrin advised they had landed the Lunar Module on the moon’s surface, and Duke acknowledged the achievement:
“Roger, Tranquility, we copy you on the ground. You got a bunch of guys about to turn blue. We’re breathing again. Thanks a lot!”
Almost three years later, Charlie Duke also landed on the moon as part of the Apollo 16 mission, becoming the 10th man to step onto the moon’s surface.
Charlie Duke’s biography.