It was the last group to be selected during the Project Apollo era, and the first since the Mercury Seven in which all members were active-duty military personnel, and all made flights into space.

The Manned Orbiting Laboratory (MOL) was a semi-secret United States Air Force (USAF) space project, with a public face but a covert reconnaissance mission.

The former MOL astronauts went on to form the core of early Space Shuttle pilots, upgrading to commander after their first flight, and flying 17 missions between them.

[10] Fourteen of its seventeen astronauts were still with the program; John L. Finley had returned to the Navy, Michael J. Adams transferred to the X-15, and Robert H. Lawrence died during training.

Manned Spacecraft Center director Robert R. Gilruth agreed, but Deputy Administrator of NASA George Mueller thought that sooner or later the agency would need help from the USAF, and maintaining good relations was good policy.

[34] While Slayton warned the MOL transfers that they would probably not fly until the space shuttle around 1980, he did have many duties for them.

[36] On February 24, 1976, NASA announced the two crews of two astronauts to fly the Approach and Landing Tests in the Space Shuttle Enterprise.

[38] All seven MOL astronauts flew on the Space Shuttle,[33] starting with Crippen on STS-1, the first mission, in April 1981.

Peterson's extravehicular activity on that mission, the first in the Space Shuttle program, was the only one conducted by a member of the group.