The Mathematicians' Moon was a moon in orbit of the psychoplasmic Skaro within the Golden City Zone of the Dalek Dome, entirely populated by Quadruple-Brained Algebraists whose calculations sustained the quantum-powered reality gates which in turned sustained the psychoplasmic constructs of Daleks in the real universe. When the Dalek Alliance attacked the Golden City Zone, the Golden Emperor attempted to flee on a rocket. Boarding the craft, the Fourteenth Doctor sabotaged its navigation systems, sending it crashing into the Mathematicians' Moon, destroying it and dissipating the construct Daleks who had made it to N-Space. (COMIC: Liberation of the Daleks [+]Alan Barnes, DWM Comics (Panini Comics, 2022-2023).)
Tardis