K37 Gem 5
From Tardis Wiki, the free Doctor Who reference
K37J5 is the designation of a Black hole on the very edge of Mutter's Spiral. In the 44th century the New British Empire sent two expeditions to the vicinity of the Black hole in order to find the planet Krop Tor and to find out what was keeping it in orbit. Its existence was known by the Valtino, who believed it was a demon. (DW: The Impossible Planet, The Satan Pit)
