What is the Arctic Circle?
The Arctic Circle is an imaginary line around Earth at about 66.5 degrees north latitude. North of it, there is at least one day a year when the Sun does not set and one day when it does not rise.
On the summer solstice, around June 21, places on the Arctic Circle experience 24 hours of daylight, known as the midnight sun. On the winter solstice, around December 21, they have a full day without the Sun rising, called polar night. The farther north you go, the longer these periods last, up to six months at the North Pole.
The Arctic Circle passes through eight countries: Norway, Sweden, Finland, Russia, the United States through Alaska, Canada, Denmark through Greenland and Iceland, where it crosses the small island of Grímsey. The region north of the circle is home to about four million people, including Indigenous peoples such as the Sámi and Inuit.
A moving line
The position of the Arctic Circle slowly shifts because Earth's axial tilt changes slightly over time. Currently, it is moving north by about 14 to 15 meters per year. The Antarctic Circle, at about 66.5 degrees south, is its southern equivalent.
Did You Know?
Rovaniemi in Finnish Lapland, on the Arctic Circle, promotes itself as the official hometown of Santa Claus.