21 November

21 November was a date.
In 1962, Peri Brown's parents, Janine and Paul Brown, were married. (AUDIO: Peri and the Piscon Paradox)
The Thirteenth Doctor, Yaz, and Dan were brought to Medderton in 1967 by a Weeping Angel who seized control of her TARDIS. (TV: Village of the Angels)
In 1979, Ian Dury and the Blockheads performed in concert at Sheffield, England. (TV: Tooth and Claw)
21 November 2059 was a fixed point in time: Bowie Base One, the first human colony on Mars, was destroyed and its crew was killed. The death of the captain, Adelaide Brooke, would inspire her granddaughter, Susie Fontana Brooke, to venture out into space, ensuring humanity's place among the stars. When the Tenth Doctor visited, the Flood infected the base. When Adelaide initiated Action 5, as per history, the base was, sixteen weeks into its mission, destroyed.
thumb|left|The Doctor describes the day's events to Adelaide. (TV: The Waters of Mars)
With the rebellious Doctor's intervention, defying the Laws of Time, Brooke, Yuri Kerenski and Mia Bennett were all saved and returned to Earth in his TARDIS. Disgusted by the "Time Lord Victorious", Adelaide shot herself, fixing the timelines, except dying on Earth instead. (TV: The Waters of Mars, PROSE: Time Traveller's Diary)
In 2119, the Drum brought an alien spaceship aboard during its mining operations. Jonathan Moran was killed by the "ghost" of Albar Prentis burning him alive with the spaceship's engines, so that Moran himself became a ghost to function as a transmitter for the spaceship's coordinates. (TV: Under the Lake)