Did you know that there are places on Earth where the Sun never rises in the Winter and never sets in the Summer?
In northern winter the South Pole is angled toward the Sun and thus is continually sunlit as the Earth spins.
(click to enlarge WARNING large image: 6.2MB)

The Earth undergoes two motions simultaneously: it rotates on its axis once in 24 hours and it orbits the Sun along the ecliptic once each year. Because the Earth's axis of rotation is tilted by 23.5 degrees to the ecliptic, at some times during the year the South Pole points more towards the Sun than the North Pole (as in fig. 1) and vice versa. During northern winter, people near the North Pole will not see the Sun rise, and those near Antarctica will not see it set. The number of daylight hours varies with the season and with your location on Earth's surface. What happens in your part of the world? To explore this further, check out the Earth's Seasons animation.

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