USS Challenger (NCC-2032)
The USS Challenger (NCC-2032) was a Federation starship operating in the 23rd century. The Challenger was among the task force that would have been assembled for the abandoned assault code-named Operation Retrieve, which would have rescued Captain James Kirk and Doctor Leonard McCoy from Qo'noS in 2293. (Star Trek VI: The Undiscovered Country)
- The icon representing the Challenger on the barely-visible chart in the Federation President's office was a Constitution-class starship, according to Michael Okuda. However, all ships on that chart save the USS Excelsior had the same icon, so it's very unlikely that the Challenger 's class can be determined.
- The existence of this ship is implied by the other Challenger-class starship seen in service on TNG, among the wreckage of Wolf 359 in "The Best of Both Worlds, Part II." The known modern design of the Challenger class does not permit the interpretation that it is the same ship as the NCC-2032 above.
USS Challenger (NCC-71099)
The USS Challenger (NCC-71099) was a Galaxy-class starship launched sometime prior to 2377. The Challenger was one of the starships which intercepted the Borg sphere which carried the USS Voyager back to the Alpha Quadrant in 2378. (VOY: "Endgame")
In an alternate timeline created after the USS Voyager's attempt to use quantum slipstream drive resulted in the ship being destroyed, the Challenger was captained by Geordi La Forge in 2390. The vessel was assigned to pursue and capture the Delta Flyer, which had been stolen by former USS Voyager crew members Chakotay and Harry Kim. The Challenger managed to inflict severe damage on the Flyer, causing a warp core breach. However, Harry Kim was successful in transmitting a message to Voyager into the past, giving them instructions to collapse the slipstream and avert the disaster. (VOY: "Timeless")
The Challenger was a computer-generated model; its presence during VOY: "Endgame" is inferred by the fact that the name and registry on the model was left over from VOY: "Timeless." The Challenger also appeared in the 2001 and 2002 Ships of the Line calendars from Pocket Books, although parts of the CGI image were still labeled "Enterprise" and "NCC-1701-D." Its registry number, NCC-71099, is a tribute to the space shuttle orbiter Challenger, OV-099, lost in January 1986. Like the USS Venture, the ship's name is emblazoned below the registry number on the ventral side of its saucer section. The Venture model was the first to do this.
In the non-canon Pocket TOS novel "The Return" by William Shatner (with Judith and Garfield Reeves-Stevens), a Galaxy-class starship Challenger is mentioned existing earlier in 2371. In the novel the ship was commanded by a Vulcan, Captain Simm, and, docked at Deep Space 9, was the scene of a fight between Jean-Luc Picard and a Borg-assimilated James T. Kirk.