Doctor Who: 10 Things You Didn't Know About UNIT
4. There's A UNIT Moonbase
Russell T Davies' one and only script for the Eleventh Doctor – the Sarah Jane Adventures serial Death of the Doctor – revealed that UNIT has a working Moonbase!
Death of the Doctor teamed up two out of three of the Third Doctor's companions for an adventure with Matt Smith's Eleventh Doctor. Summoned to the Doctor's funeral, Sarah Jane Smith and the gang arrive at UNIT Base Five, where it's noted that some pretty important people can't actually make it to the funeral.
It's mentioned that Liz Shaw is at a UNIT base on the Moon, and that the Brigadier is still in Peru. A Moonbase makes tactical sense for protecting the Earth from space, which raises the question of if there are now armed UNIT astronauts, or UNIT spaceships!
This idea of a UNIT Moonbase was admittedly a throwaway line, but predictably, Doctor Who expanded media has taken the idea and ran with it.
Gary Russell's Eleventh Doctor novel Horror of the Space Snakes reveals that UNIT handed its Moonbase over at some point around 2023. The new owners renamed it Moonbase Laika, and it was that same Moonbase that came under attack from the Cybermen in the Second Doctor serial called... The Moonbase.
Someone really should warn these people that they've built a base on top of a massive egg.