Manned Orbiting Laboratory
The Manned Orbiting Laboratory (MOL) was part of the United States Air Force (USAF) human spaceflight program in the 1960s. The project was developed from early USAF concepts of crewed space stations as reconnaissance satellites, and was a successor to the canceled Boeing X-20 Dyna-Soar military reconnaissance space plane.
Source: Wikipedia — Manned Orbiting Laboratory (CC BY-SA 4.0)