Mitchell was selected in 1966 as part of NASA's fifth astronaut group. He was assigned to the support crew for Apollo 9, then was designated as backup Lunar Module Pilot for Apollo 10. This placed him in rotation for Apollo 13, but his crew was switched to Apollo 14 so that Commander Alan Shepard, who had been grounded by a medical problem since the Gemini program, could train longer. During the Apollo 13 crisis, Mitchell was a part of the Apollo 13 Mission Operations Team and as such was awarded the Presidential Medal of Freedom by President Richard M. Nixon in 1970. He worked in an Apollo simulator to help bring the crew back. One issue he worked on was how to "fly" (meaning control the attitude of) the Lunar Module with an inert Apollo Command/Service Module attached to it. (Usually it was the other way around, but the Service Module was damaged during that mission.) He then went to serve as Lunar Module Pilot on Apollo 14, landing with Shepard aboard the Lunar Module Antares on February 5, 1971, in the hilly upland Fra Mauro Highlands region of the Moon. They stayed on the Moon for 33 hours, deployed and activated lunar surface scientific equipment and experiments, and collected almost 100 pounds of lunar samples for return to Earth. Other Apollo 14 achievements include: only use of the Mobile Equipment Transporter (MET); first successful use of color television with a new Vidicon tube; longest distance traversed on foot on the lunar surface; largest payload placed in lunar orbit; first use of shortened lunar orbit rendezvous techniques; and first extensive orbital science period conducted during CSM solo operations. In completing his first space flight, Mitchell logged a total of 216 hours and 42 minutes in space. He was subsequently designated to serve as backup Lunar Module Pilot for Apollo 16. During the mission, he took photos, including the one with Shepard raising the American flag. In the photo Mitchell's shadow is cast over the lunar surface near the flag. That photo was listed on Popular Science's photo gallery of the best astronaut selfies.