Tropic of Cancer (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. There are approximately 13 hours, 35 minutes of daylight during the summer solstice. During the winter solstice, there are 10 hours, 41 minutes of daylight. Starting
Equator is derived from medieval Latin word "aequator", in the phrase "circulus aequator diei et noctis," meaning ‘circle equalizing day and night’, from the Latin word "aequare" meaning ‘make equal’. The latitude of the Earth's equator is, by definition, 0° (zero degrees) of arc. The Equator is one of the five notable circles of latitude on Earth; the other four are both polar circles (the Arctic Circle and the Antarctic Circle) and both tropical circles (the Tropic of Cancer and the Tropic of Capricorn). The Equator is the only line of latitude which is also a great circle — that is,