7 December

On 7 December 1952, the Third Doctor and Sarah Jane Smith, then being assisted be former adversary Tommy Ramsey, turned back a Xhinn advance invasion fleet. The cost of victory was, however, high, with many ordinary Londoners losing their lives. (PROSE: Amorality Tale)

According to a calendar on the Snowcap base, 7 December 1986 was a Sunday. (TV: The Tenth Planet)