Jack Swigert, in full John Leonard Swigert, Jr., (born August 30, 1931, Denver, Colorado, U.S.—died December 27, 1982, Washington, D.C.), was an American NASA astronaut, test pilot, mechanical engineer, aerospace engineer, United States Air Force pilot, and politician. In April 1970, as command module pilot of Apollo 13, he became one of twenty-four astronauts who flew to the Moon.
An astronaut (or cosmonaut) is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft.
Although generally reserved for professional space travelers, the terms are sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and tourists.