Tropic of Cancer

Coordinates: 23°26′12.5″N 0°0′0″W / 23.436806°N -0.00000°E / 23.436806; -0.00000 (Prime Meridian)Road sign south of Dakhla, Western Sahara marking the Tropic of Cancer. The sign was placed by Budapest-Bamako rally participants; thus, the inscription is in English and Hungarian.Sign marking the Tropic of Cancer a few miles from Rann of Kutch, Gujarat, IndiaSign marking the Tropic of Cancer in Madhya Pradesh, IndiaSign marking the Tropic of Cancer on National Highway 34 in Nadia District, West Bengal, IndiaRuisui Tropic of Cancer Marker in Ruisui Township, Hualien County, Taiwan Coordinates: 23°26′12.5″N 0°0′0″W / 23.436806°N -0.00000°E / 23.436806; -0.00000 (Prime Meridian) The Tropic of Cancer, which is also referred to as the Northern Tropic, is the most northerly circle of latitude on Earth at which the Sun can be directly overhead. This occurs on the June solstice, when the Northern Hemisphere is tilted toward the Sun to its maximum extent. It is currently 23°26′12.3″ (or 23.43675°) north of the Equator. Its Southern Hemisphere counterpart, marking the most southerly position at which the Sun can be directly overhead, is the Tropic of Capricorn. These tropics are two of the five major circles of latitude that mark maps of Earth; the others being the Arctic and Antarctic Circles and the Equator. The positions of these two circles of latitude (relative to the Equator) are dictated by the tilt of Earth's axis of rotation relative to the plane of its orbit. When this line of latitude was named in the last centuries BC, the Sun was in the constellation Cancer (Latin for crab) at the June solstice, the time each year that the Sun reaches its zenith at this latitude. Due to the precession of the equinoxes, this is no longer the case; today the Sun is in Taurus at the June solstice. The word 'tropic' itself comes from the Greek 'trope (τροπή)', meaning turn (change of direction, or circumstances), inclination, referring to the fact that the Sun appears to 'turn back' at the solstices. The Tropic of Cancer's position is not fixed, but constantly changes because of a slight wobble in the Earth's longitudinal alignment relative to its orbit around the Sun. Earth's axial tilt varies over a 41,000-year period from 22.1 to 24.5 degrees and currently resides at about 23.4 degrees. This wobble means that the Tropic of Cancer is currently drifting southward at a rate of almost half an arcsecond (0.468″) of latitude, or 15 metres, per year (it was at exactly 23° 27′N in 1917 and will be at 23° 26'N in 2045). See axial tilt and circles of latitude for further information. North of the tropic are the subtropics and the North Temperate Zone. The equivalent line of latitude south of the Equator is called the Tropic of Capricorn, and the region between the two, centered on the Equator, is the tropics.