Astrology (from Greek: αστρολογία = άστρον, astron, "star" + λόγος, logos, "word") refers to any of several traditions or beliefs in which knowledge of the apparent positions of celestial bodies is held to be useful in understanding, interpreting, and organizing knowledge about reality and human existence on earth. All traditions are based on the relative positions and movements of various real and construed celestial bodies as seen at the time and place of the birth or other event being studied. These are chiefly the Sun, Moon, planets, Ascendant & Midheaven axes, and the lunar nodes. A practitioner of astrology is called an astrologer, or sometimes an astrologist. Astromancy, divination by the stars, is a slightly archaic synonym for astrology (likewise for astromancer and the rather rarely used astromancist).
Many of those who practice astrology believe the positions of certain celestial bodies either influence or correlate with people's personality traits, important events in their lives, and even physical characteristics.
Astrology is not considered to be a science, but is more appropriately an art, and is separate from astronomy, the scientific study of outer space. The calculations performed in astrology involve arithmetic and simple geometry and serve to locate the apparent location of heavenly bodies on desired dates and times based on tables constructed by astronomers. There have been astrologers who claim to try to put astrology on a sound scientific basis, but for most it is an art that merges calculations with their own intuitive perceptions. For most astrologers the purported relationship between the celestial bodies and events on earth need not be causal, nor even scientific.
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