Tropic of Capricorn
The Tropic of Capricorn, or Southern tropic, marks the most southerly latitude on the Earth at which the Sun can be directly overhead. This event occurs at the December solstice, when the southern hemisphere is tilted towards the Sun to its maximum extent.
The Tropic of Capricorn is the dividing line between the Southern Temperate Zone to the south and the tropics to the north. The position of the Tropic of Capricorn is not fixed, but rather it varies in a complex manner over time.