Tropic of Capricorn, parallel of latitude at 23°30' south of the equator; it is the southern boundary of the tropics. This parallel marks the farthest point south at which the sun can be seen directly overhead at noon; south of the parallel the sun appears less than 90° from the northern horizon at any day of the year. The sun reaches its vertical position over the Tropic of Capricorn at about Dec. 22, the summer solstice for the Southern Hemisphere. The term Capricorn comes from the Latin words caper [goat] and cornu [horn] and is the name given to one of the 12 constellations in the zodiac.

or Capricornus

(Latin: “Goat horn”) In astronomy, the constellation lying between Aquarius and Sagittarius; in astrology, the tenth sign of the zodiac, governing approximately the period December 22–January 19. It is represented as a goat with what appears to be a fishtail. One explanation for this odd depiction is that it derives from the Greek myth of Pan. To avoid the monster Typhon, Pan jumped into the water just as he was changing into animal shape. The half of his body above water became a goat, while the submerged half took the shape of a fish. Another relates the form to the Mesopotamian deity Enki (see Ea).

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