Cardinal sign (astrology) Cardinal sign (astrology) The practice of astrology recognizes four cardinal signs of the zodiac: Aries, Cancer, Libra, and Capricorn — sometimes called reacting signs. It associates those people born "under" one of these with certain human behaviors and traits like being active, self-motivated, insightful and ambitious. The word "cardinal" originates from the Latin word for "important," since they each mark the turning point of a temperate season. They were called "moveable" by traditional astrologers because, as Bonatti says, the "air" changes when the Sun enters each of these signs, bringing a change of season. Sometimes the word "cardinal" is confused
Zodiac used to determine the boundaries of astronomical constellations that lie in the vicinity of the zodiac, which are, and always have been, irregular in their size and shape. The convention of measuring celestial longitude within individual signs was still being used in the mid-19th century, but modern astronomy now numbers degrees of celestial longitude from 0° to 360°, rather than 0° to 30° within each sign. The use of the zodiac as a means to determine astronomical measurement remained the main method for defining celestial positions by Western astronomers until the Renaissance, at which time preference moved to the equatorial