He flew spaceflight missions during Project Gemini and then flew to the moon twice, first to orbit as the Lunar Module Pilot for Apollo 10, and then to land as the Commander of Apollo 17. He received a Master’s degree in Aeronautical Engineering from the U.S. Naval Postgraduate School in 1963, when he became one of fourteen people selected for NASA’s Astronaut Group 3, along with Buzz Aldrin. During the Gemini mission, Cernan became the second American to go on a spacewalk, and the third person to ever perform extravehicular activity (EVA), staying outside of the spacecraft in his suit for 2 hours and 7 minutes.
During the Apollo 17 mission, Cernan and Lunar Module Pilot Harrison H. Schmitt spent more time on the moon than anyone before them, a total of just over three days and drove the Lunar Rover more than 22 miles over of the lunar surface. Cernan’s experience on the Moon was described in his 1999 memoir, The Last Man on the Moon, as well as in the 2016 documentary of the same name.