Gene CernanEugene A. Cernan was an astronaut who flew in the
Gemini and Apollo space programs. Cernan is one of only three
men to voyage to the moon on two different occasions (the others
being Jim Lovell and John Young), and one of only twelve men to
walk on the moon. Cernan orbited the moon on Apollo 10, and
landed on the moon on Apollo 17. He also flew on Gemini 9. Gene
Cernan is the author of The Last Man on the Moon, his memoirs of
the Apollo program.