Antarctic Circle

The position of the Antarctic Circle is not fixed and, not taking account of the nutation, currently runs 66°33′50.3″ south of the Equator.

Its latitude depends on the Earth's axial tilt, which fluctuates within a margin of more than 2° over a 41,000-year period, due to tidal forces resulting from the orbit of the Moon.

[3][4] Directly on the Antarctic Circle these events occur, in principle, exactly once per year: at the December and June solstices, respectively.

Mirages on the Antarctic continent tend to be even more spectacular than in Arctic regions, creating, for example, a series of apparent sunsets and sunrises while in reality the sun remains below the horizon.

There is no permanent human population south of the Antarctic Circle, but there are several research stations in Antarctica operated by various nations that are inhabited by teams of scientists who rotate on a seasonal basis.