Starbase 42 was a Starfleet installation in operation in the 23rd and 24th centuries.
In 2268, the station was under the command of Commodore Krinsky, and was in the process of being decommissioned, when dilithium deposits were found on the planet below. Klingon infiltrators killed Krinsky, and the IKS D’k’tahg arrived to take the dilithium. The crews of the USS Enterprise and USS Constellation battled Klingons on the station, and eventually expelled them. (TOS novel: Errand of Vengeance: River of Blood), (TOS novel: Errand of Fury: Seeds of Rage).
In 2272, the Enterprise went to Starbase 42 following a visit to Cragon V. (TOS novel: Home is the Hunter).
In 2333, the USS Stargazer went to Starbase 42 for new orders. (STA novel: Progenitor).
- In this novel, the station is described as brand new. It can be conjectured that either the old Starbase 42 had been heavily refurbished, or else Starfleet had given the designation to an entirely new facility.
Charles, Morgan, and Robin Lefler lived on Starbase 42 sometime prior to 2353, when they moved to Tantalus. (NF short story: Lefler's Logs)
In 2365, Commander William T. Riker was dropped off here to assemble a team to go to Paradise for a mission. (TNG novel: A Rock and a Hard Place).
Sometime prior to 2374, Worf attended a meeting with Starfleet Command on the station to discuss Klingon affairs. (TNG novel: Planet X).
In 2376, Captain David Gold and Commander Sonya Gomez were summoned to Starbase 42 for a briefing. (SCE novel: Interphase, Book One).