Tropic of Cancer
From Tardis Wiki, the free Doctor Who reference
According to a book owned by Chloe Webber, the Tropic of Cancer was a line of latitude in the Northern Hemisphere (TV: Fear Her [+]Loading...["Fear Her (TV story)"]) opposite to the Southern Hemisphere's Tropic of Capricorn on the planet Earth. (PROSE: Iceberg [+]Loading...["Iceberg (novel)"]) The Equator, which divided the Earth horizontally, ran between the Tropics of Cancer and Capricorn. (TV: Fear Her [+]Loading...["Fear Her (TV story)"])