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Country: Taiwan

Distance: 8,514 km

Travel time:  10 days

On postcard: Tropic of Cancer, Fengbin

The Tropic of Cancer, also referred to as the Northern tropic, is the circle of latitude on the Earth that marks the most northerly position at which the Sun may appear directly overhead at its zenith. This event occurs once per year, at the time of the June solstice, when the Northern Hemisphere is tilted toward the Sun to its maximum extent.

Its Southern Hemisphere counterpart, marking the most southerly position at which the Sun may appear directly overhead, is the Tropic of Capricorn. These tropics are two of the five major degree measures or major circles of latitudethat mark maps of the Earth, besides the Arctic and Antarctic Circles and the Equator. The positions of these circles of latitude (other than the Equator) are dictated by the tilt of the Earth's axis of rotation relative to the plane of its orbit.

Name

The imaginary line is called the Tropic of Cancer because when it was named, the Sun was in the direction of the constellation Cancer(Latin for crab) at the June solstice. However, this is no longer true due to the precession of the equinoxes. According to International Astronomical Union boundaries, the Sun now is in Taurus at the June solstice. According to sidereal astrology, which divides the zodiacinto 12 equal parts, the Sun is in Gemini at that time. The word "tropic" itself comes from the Greek τροπή (tropi), meaning turn, referring to the fact that the Sun appears to "turn back" at the solstices.

Geography

The Tropic of Cancer currently (Epoch 2011) lies 23° 26′ 16″ north of the Equator. Its position is not fixed, but varies in a complicated manner over time. It is presently drifting south at the rate of almost half a second (0.47″) of latitude per year (it was at exactly 23º 27' in year 1917). See circles of latitude for further information.

North of Tropic of Cancer 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.