Space Station Chimera was a scientific research space station in the Third Zone, where the scientists Kartz and Reimer were conducting time travel experiments. Dastari was the station Head of Projects, and Shockeye of the Quawncing Grig was the chef. The Time Lords sent the Doctor to the station to put a stop to the experiments. The station was then attacked by Sontarans.
Upon seeing the station on the TARDIS scanner screen, Jamie McCrimmon was amazed by its size, calling it "like 20 castles in the sky." (DW: The Two Doctors)
Behind the scenes
In the novelisation of The Two Doctors the station is called "Space Station J7."