Spacedock A spacedock , or drydock , was a facility capable of docking starship s for maintenance . Most spacefaring species had some type of spacedock , and they thus varied widely in design . The United Federation of Planets and United Earth had spacedocks that most often took the form of a free - standing , orbital , single - starship - sized " cage " . This form of spacedock was virtually synonymous with the word drydock . Generally , these cage designs were used for major construction or refit s and could be part of a shipyard . Some spacedocks , however , were part of starbase s and outpost s , and allowed for more secure repairs in a totally enclosed , multi - functional facility . The enjoyed at least the final stages of its construction in such a facility orbiting Earth . History . " In the mirror universe year 2155 , the Tholian s took the to a spacedock built into an asteroid - moon in orbit around a gas giant and began a salvage operation , but were unable to finish because the ship was stolen by Commander of the . " ( ) " In 2259 of the alternate reality , a facility affiliated with Section 31 was in orbit of the Jovian moon Io . Known as the Io Facility , it was where the was constructed and launched . " ( ) " In 2263 , the was under construction in a spacedock located in one of the space lane s of Yorktown Station . " ( ) In 2371 , all of Earth ' s spacedocks were erased from existence after the death of Gabriel Bell in 2024 . They , and the correct timeline , were restored after Benjamin Sisko assumed Bell ' s identity and successfully brought the Bell Riots to their original conclusion . ( ) The Utopia Planitia Fleet Yards contained a number of drydocks . The spent some time in a drydock at Utopia Planitia before its launch in 2371 . ( ) In 2373 , Starfleet and the Klingon Defense Force attacked and destroyed the Cardassian spacedocks on Torros III . ( ) Also in that year , Chief Miles O ' Brien told Captain Sisko that a spacedock would be a better place to repair the than Deep Space 9 after Michael Eddington ' s cascade virus damaged the ship . ( ) There were also spacedocks in orbit of Trelka V in the 2370s . Three starships were docked there in 2375 when Martok led the attack on the Trelka starbase . ( ) Appendices . Background information . The first mention of a spacedock is in . The script for " The Motion Picture " calls the structure an " Orbital Dry Dock " . The terms " Spacedock " and " Drydock " have been used interchangeably to describe the same structures . NAR - 30974 , the facility the was launched from in , had markings saying it was a " Starfleet Drydock " while the script and dialogue used " spacedock . " " Voyager " launched from a similar , if smaller , facility that was referred to as a " drydock " in dialogue and the scripts in the episode . Very little is known about the enclosed spacedocks seen in the and TNG episodes . Their dimensions , internal layout , regular and maximum compliment , and if the spacedock was open to civilians or if it was restricted to Starfleet personnel , is unknown . There seem to be very different sizes of the enclosed spacedocks , despite having the same basic " mushroom " design in the 23rd century as they do in the 24th . It is known , for instance , that some can accommodate a starship , although the facility seen in the movies – whose space doors seem barely wide enough to accommodate the " Enterprise " – seem able to admit nothing larger than an vessel . This is because stock footage of the original " Enterprise " entering the dock was superimposed with the new , larger entering the same port .