Science Fair Project Encyclopedia
The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. This is the parallel of latitude that runs 66° 33' 38" north of the Equator. Everything north of this circle is known as the Arctic, and the zone just to the south of this circle is the Northern Temperate Zone.
The Arctic Circle marks the southern extremity of the polar day of the summer solstice in June and the polar night of the winter solstice in December. Within the Arctic Circle, the arctic Sun is above the horizon for at least 24 continuous hours per year, in conjunction with the Arctic's Summer Solstice. Likewise, in conjunction with the Arctic's Winter Solstice, the Arctic sun will be below the horizon for at least 24 continuous hours.
Due to precession, the Arctic Circle fluctuates within a band of 250 kilometres, moving by about half a kilometre in one year.
Countries which have significant territory within the arctic circle include:
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