Why does Antarctica have long periods of daylight and darkness?

Antarctica experiences long periods of daylight and darkness primarily due to the Earth's axial tilt. The planet is tilted approximately 23.5° relative to the plane of its orbit around the Sun, a geometry that dictates the seasonal distribution of sunlight across the globe.12

Because of this inclination, the polar regions experience extreme variations in solar exposure:

• Summer: During the southern summer, the South Pole is tilted toward the Sun, resulting in continuous daylight.13
• Winter: During the southern winter, the South Pole is tilted away from the Sun, leading to continuous darkness.12

The duration of these periods depends on latitude. At the Antarctic Circle, there is at least one 24-hour period of continuous day or night each year. As one moves southward toward the geographic South Pole, the length of these periods increases, reaching up to six months of continuous light or darkness (though these periods are modified by twilight).132