The Apollo Astronaut program was a series of missions conducted by the United States during the 1960s and 1970s. The astronauts involved in these missions included Neil Armstrong (4 letters), DEKE Slayton (4 letters), James Irwin (5 letters), Wally Schirra (7 letters), Michael COLLINS (7 letters), Eugene Cernan (6 letters), Alan BEAN (4 letters), Edwin Aldrin (6 letters), and James Lovell (6 letters). These brave men were the first to explore space and set foot on the moon, making them some of the most famous astronauts in history.