https://en.m.wikipedia.org/wiki/Jack_Swigert

Swigert gained some notoriety as NASA's first unmarried astronaut, living in a bachelor pad in Houston, a luxury apartment which included beer and wine dispensers and a hi-fi stereo system. In the early days of Project Mercury, the agency's requirements for astronauts were rather strict and included the expectation that all of them be married family men, but as the 1960s ended, social attitudes in America were quickly changing. Therefore, NASA decided to loosen the restrictions.