The Moon

The largest natural satellite of Earth, The Moon has a storied history.

Origin
The specific physical origin is unknown. It wasn't seen to form at the same time as the Earth (DW: The Runaway Bride), and the Silurians reported that it did not appear in Earth's sky until their time (DW: Doctor Who and the Silurians).

Human bases
By the late 21st century, Humans had at least one base on the Moon. One functioned as a T-Mat relay, co-ordinating T-Mat on Earth (DW: The Seeds of Death),

By 2070, a base housed the Gravitron, a machine for regulating Earth's weather. (DW: The Moonbase).

By 2540, it served as a penal colony for dissidents against the war between Earth's empire and the Draconians. (DW: Frontier in Space)

By the time of the Fourth Great and Bountiful Human Empire, the Earth had five moons. A penal colony still existed at this time. (DW: The Long Game)


 * We do not know if, by this time, the original natural moon still existed or the nature (artificial or natural) of the moons mentioned in passing.

Other bases

 * Some time before the late 20th century, the Cybermen established a base on the dark side of the Moon which served as the staging area for a fleet poised to invade Earth. It also could fire missiles at approaching craft such as the Doctor's TARDIS. (DW: The Invasion)


 * The Cybermen active in London in 1985 also maintained a moonbase, but whether this was the same one mentioned above is unknown - as these Cybermen were time travellers, it seems doubtful.


 * Prior to 2001 there was a base on the Moon at Tycho crater. Movements suggesting active lifeforms further north in the Eratosthenes crater were spotted as early as 1924. (visittorchwood.co.uk).

Other information

 * Moonlight, concentrated into a laser-like beam, killed the Host at Torchwood House. (DW: Tooth and Claw)


 * The Moon was, during and before the 21st century, "Neutral Ground" under Galactic Law, meaning that if law-enforcement agents such as the Judoon had business involving Earth, they needed to move the place they would have needed to go to the Moon. (DW: Smith and Jones)


 * As mentioned above, in the early 21st century the Royal Hope Hospital was transported from London to the Moon by Judoon searching for a plasmavore murderer. Their target destroyed, the hospital was returned to Earth with the loss of only one Human life.