23.5 degrees South Latitude is known as the Tropic of Capricorn. This latitude circle is one of the five major circles of latitude that mark maps of the Earth and distinguishes the southern boundary of the tropics. The Tropic of Capricorn is significant because it represents the southernmost point on Earth at which the Sun can be directly overhead. This occurs during the December solstice when the Southern Hemisphere is tilted towards the Sun.