Tropic of Cancer
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- Tropic of Cancer is also the name of a novel by Henry Miller, first published in 1934.
Image:TROPIC OF CANCER021106.jpg The Tropic of Cancer (cancer (♋) is Latin for crab), one of the five major circles of latitude that mark maps of the Earth, is the parallel of latitude that lies 23° 26' 22" north of the Equator.
It is the farthest northern latitude at which the sun can appear directly overhead, which occurs on the June solstice. North of this line is the subtropics and Northern Temperate Zone. The Tropic of Capricorn is at the opposite latitude south of the Equator. South of the Tropic of Cancer and north of the Tropic of Capricorn are the Tropics.
It is difficult to specify an exact location for the Tropic of Cancer because the obliquity of the ecliptic varies between 21.5° and 24.5° with a 41,000 year periodicity. Its value also varies by ±9 arcseconds over a period of 18.6 years as a consequence of a phenomenon called nutation. This means the "real" Tropic of Cancer can be nearly 300 meters north or south of the expected location.
The Tropic of Cancer passes through the following countries (going east):
- United States of America (Hawaii) - misses every island, passing between Nihoa and Necker Island
- Mexico
- Bahamas
- Western Sahara (claimed by Morocco)
- Mauritania
- Mali
- Algeria
- Niger
- Libya
- Chad - North-most point is defined by Tropic of Cancer
- Egypt
- Saudi Arabia
- United Arab Emirates
- Oman
- India
- Bangladesh
- Myanmar
- China
- Taiwan
The line is called the Tropic of Cancer because when it was named, the sun was in the constellation of Cancer when it appeared directly overhead at this latitude during the June solstice. However, due to precession of the equinoxes, the June solstice is now in the constellation Taurus.
According to Fédération Aéronautique Internationale's rules, to qualify as a circumnavigation, a flight must be no less than the length of Tropic of Cancer (36,787.559 km), as well as cross all meridians and end on the same airfield where it started.
See also
Template:Geo-term-stubca:Tròpic de Càncer de:Nördlicher Wendekreis es:Trópico de Cáncer eo:Tropiko de Kankro fr:Tropique du Cancer gl:Trópico de Cáncer it:Tropico del Cancro hu:Ráktérítő nl:Kreeftskeerkring no:Krepsens vendekrets pt:Trópico de Câncer fi:Kravun kääntöpiiri sv:Kräftans vändkrets tr:Yengeç Dönencesi vi:Chí tuyến Bắc zh:北回歸線