Part of the San Francisco Fleet Yards, an orbital drydock facility was a Starfleet ship construction and repair facility in Earth orbit in the late 23rd century and was usually paired with an orbital office complex which serviced it. Such facilities were designed to be easily reconfigured to fit the many shapes and sizes of Starfleet vessels.
In 2271, the U.S.S. Enterprise was nearing the end of an 18-month refit at an orbital drydock when it was assigned, under command of Admiral James T. Kirk, to investigate a massive cloud anomaly which had been observed destroying several Klingon warships. The Enterprise later returned to a similar drydock facility, launching again in 2285.
As portrayed in Star Trek: The Motion Picture (Film, 1979)
The drydock model was originally conceived by designer Mike Minor for the pilot episode of Star Trek: Phase II but was later redesigned for The Motion Picture by Andrew Probert, to better suit the increased resolution needed for a theatrical film release. The physical model was built by Magicam, and a partial, even more detailed model was built for closeup photography.
Custom made cameras and lenses had to be constructed to photograph the drydock. Director Robert Wise delegated the task of filming the drydock sequence to Special Photographic Effects Supervisor Douglas Trumbull, who wanted to “just let the audience love the Enterprise”.