THE ZODIAC

Zodiac, imaginary belt in the celestial sphere, extending about 8° on either side of the ecliptic, the apparent path of the Sun among the stars. The width of the zodiac was determined originally so as to include the orbits of the Sun and Moon and of the five planets (Mercury, Venus, Mars, Jupiter, and Saturn) that were known to the people of ancient times. The zodiac is divided into 12 sections of 30° each, which are called the signs of the zodiac. Starting with the vernal equinox and then proceeding eastward along the ecliptic, each of the divisions is named for the constellation situated within its limits in the 2nd century bc. The names of the zodiacal signs are Aries, the Ram; Taurus, the Bull; Gemini, the Twins; Cancer, the Crab; Leo, the Lion; Virgo, the Virgin; Libra, the Balance; Scorpio, the Scorpion; Sagittarius, the Archer; Capricorn, the Goat; Aquarius, the Water Bearer; and Pisces, the Fishes. Because of the precession of the equinoxes about the ecliptic, a 26,000-year cycle, the first point of Aries retrogrades about 1° in 70 years, so that the sign Aries today lies in the constellation Pisces. In about 24,000 years, when the retrogression will have completed the entire circuit of 360°, the zodiacal signs and constellations will again coincide. See Astronomy.

It is believed that the zodiacal signs originated in Mesopotamia as early as 2000 bc. The Greeks adopted the symbols from the Babylonians and passed them on to the other ancient civilizations. The Egyptians assigned other names and symbols to the zodiacal divisions. The Chinese also adopted the 12-fold division, but called the signs rat, ox, tiger, hare, dragon, serpent, horse, sheep, monkey, hen, dog, and pig. Independently, the Aztec people devised a similar system.

Rat Shu 1900 1912 1924 1936 1948 1960 1972 1984 1996 2008

Ox Niu 1901 1913 1925 1937 1949 1961 1973 1985 1997 2009

Tiger Hu 1902 1914 1926 1938 1950 1962 1974 1986 1998 2010

Hare T'u 1903 1915 1927 1939 1951 1963 1975 1987 1999 2011

Dragon Lung 1904 1916 1928 1940 1952 1964 1976 1988 2000 2012

Snake She 1905 1917 1929 1941 1953 1965 1977 1989 2001 2013

Horse Ma 1906 1918 1930 1942 1954 1966 1978 1990 2002 2014

Sheep Yang 1907 1919 1931 1943 1955 1967 1979 1991 2003 2015

Monkey Hou 1908 1920 1932 1944 1956 1968 1980 1992 2004 2016

Rooster Chi 1909 1921 1933 1945 1957 1969 1981 1993 2005 2017

Dog Kou 1910 1922 1934 1946 1958 1970 1982 1994 2006 2018

Pig Chu 1911 1923 1935 1947 1959 1971 1983 1995 2007 2019