The Antarctic Circle is one of the five major circles (or parallels) of latitude that mark maps of the Earth. A circle of latitude, on the Earth, is an imaginary East - West circle connecting all locations (not taking into account elevation that share a given EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 As of 2000, it lies at latitude 66° 33′ 39″ (or 66. 2000 ( MM) was a Leap year that started on Saturday of the Common Era, in accordance with the Gregorian calendar. Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the This article describes the unit of angle For other meanings see Degree. 56083°) south of the equator. The equator (sometimes referred to colloquially as "the Line") is the intersection of the Earth 's surface with the plane perpendicular to the The area south of the Antarctic Circle is known as the Antarctic, and the zone immediately to the north is called the Southern Temperate Zone. The equivalent line of latitude in the northern hemisphere is the Arctic Circle. The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth.

Every place south of the Antarctic Circle experiences a period of twenty-four hours' continuous daylight at least once per year, and a period of twenty-four hours' continuous night time at least once per year. That is to say, there is at least one whole day during which the sun does not set, and at least one whole day during which the sun does not rise. On the Antarctic Circle these events occur, in principle, exactly once per year, at the December solstice and June solstice respectively. Solstices occur twice a year when the tilt of the Earth's axis is most oriented toward or away from the Sun, causing the Sun to reach its northernmost and southernmost extremes Solstices occur twice a year when the tilt of the Earth's axis is most oriented toward or away from the Sun, causing the Sun to reach its northernmost and southernmost extremes This happens because the earth's axis is tilted, by approximately 23. 5 degrees, relative to ecliptic (the plane of the earth's orbit around the sun). The ecliptic is the apparent path that the Sun traces out in the sky during the year At the June solstice the southern hemisphere is tilted away from the Sun to its maximum extent, and the region of permanent darkness reaches its northern limit; at the December solstice the southern hemisphere is tilted towards the Sun to its maximum extent, and the region of permanent sunlight reaches its northern limit. Solstices occur twice a year when the tilt of the Earth's axis is most oriented toward or away from the Sun, causing the Sun to reach its northernmost and southernmost extremes Solstices occur twice a year when the tilt of the Earth's axis is most oriented toward or away from the Sun, causing the Sun to reach its northernmost and southernmost extremes

In practice several other factors affect the appearance of continuous day or night, the most important being atmospheric refraction, the altitude of the observer above sea level, mirages, and the fact that the sun is a disc rather than a point. Atmospheric Refraction is the deviation of Light or other Electromagnetic wave from a straight line as it passes through the atmosphere due to the A mirage is a naturally-occurring Optical phenomenon, in which light rays are bent to produce a displaced image of distant objects or the sky 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 under the horizon.

Due to gradual changes in the tilt of the Earth's axis, the Antarctic Circle is slowly moving. ^[1].

Contents 1 Geography and demographics 2 See also 3 References 4 External links

Geography and demographics

The continent of Antarctica forms a land mass covering much of the area within the Antarctic Circle. A continent is one of several large Landmasses on Earth. They are generally identified by Convention rather than any strict criteria with seven regions There is no permanent human population on Earth south of the Antarctic Circle. There are, however, several Antarctic research centers from various nations that are inhabited by teams of scientists that rotate on a seasonal basis. In previous centuries, some semi-permanent whaling stations were established on the continent and some of the whalers would live there for a year or more. At least three children have been born in Antarctica. ^[2] However, they were born in stations north of the Antarctic Circle.

See also

• Arctic Circle
• Equator
• Antarctic Convergence
• Solstice
• Obliquity of the Ecliptic
• Tropic of Cancer
• Tropic of Capricorn

References

External links

• Antarctic circle org
• Map

The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. The equator (sometimes referred to colloquially as "the Line") is the intersection of the Earth 's surface with the plane perpendicular to the The Antarctic Convergence, better known as the Antarctic Polar Frontal Zone (or "Polar Front" for short is a line encircling Antarctica where cold northward-flowing Solstices occur twice a year when the tilt of the Earth's axis is most oriented toward or away from the Sun, causing the Sun to reach its northernmost and southernmost extremes In Astronomy, axial tilt is the Inclination angle of a planet's rotational axis in relation to its orbital plane. For the novel by Henry Miller, see Tropic of Cancer (novel. The Tropic of Cancer, or Northern tropic, is one of five For the novel by Henry Miller, see Tropic of Capricorn (novel. A circle of latitude, on the Earth, is an imaginary East - West circle connecting all locations (not taking into account elevation that share a given Antarctica has no indigenous inhabitants but there are permanently- and seasonally-staffed research stations and former Whaling settlements

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