Three astronauts participating in Apollo desert survival training in Washington state pose with Air Force Col. Chester Bohart (second from right). Standing from left to right are Charles M. Duke, Jr., Thomas K Mattingly, Col. Bohart, and John L. Swigert. Since the Mercury Program, astronauts have taken survival courses in case they are forced to land on a remote part of the Earth where they may need to do without human help for several weeks.
