Sun, moon & rising sign calculator

Western Astrology and the Horoscope

The twelve zodiac signs go back to Babylonian astronomers of the fifth century BCE, who divided the band of sky through which the sun, moon and planets move into twelve equal sections named after constellations. In Hellenistic Egypt, from around the second century BCE, this was combined with Greek philosophy and Egyptian timekeeping to create horoscopic astrology: the casting of a chart for the moment of birth, with the rising sign (the horoskopos, 'hour-marker'), twelve houses and the positions of the seven classical planets. Ptolemy's Tetrabiblos (2nd century CE) became its most influential textbook.

Western astrology uses the tropical zodiac, which starts the signs at the spring equinox. Because of the slow precession of the equinoxes, the signs no longer line up with the constellations whose names they bear — the sun is in the constellation Pisces at the start of tropical Aries — whereas Indian (Vedic) astrology uses a sidereal zodiac fixed to the stars.

The 'sun sign' horoscope familiar today is a twentieth-century creation. It began with R. H. Naylor's newspaper column in 1930, written after the birth of Princess Margaret, and simplified astrology to the sign the sun occupied at birth. Traditional astrologers consider the moon, the rising sign and the whole chart at least as important. Scientific tests have not found that astrological signs predict personality or events, a point astrologers themselves debate.