15 October

15 October was a date.

In 1855, the Seventh Doctor, Ace and Bernice Summerfield visited Lifton. (COMIC: Cuckoo)

In 1957, the launch of Earth's first artificial satellite — named Sputnik — by the Soviet Union was reported by the BBC. (AUDIO: Unregenerate!)

In 1915, 57 Project: Twilight test subjects escaped from the Forge Alpha Facility. (PROSE: Project: Valhalla)

In 1991, the first ultra-high-energy cosmic ray was detected on Earth. It became known as the Oh-My-God particle. (PROSE: Time Traveller's Diary)

In 2070, the Telosian Cybermen attempted an invasion by attrition through poisoning and converting several members of the Moonbase on Earth's Moon. The Second Doctor, Ben Jackson, Polly Wright and Jamie McCrimmon arrived on the Moon at the same time and prevented the Cybermen proceeding with their plans to use the Gravitron against Earth. (TV: The Moonbase, PROSE: Doctor Who and the Cybermen)