The origin of the symbols for the zodiac signs appears to be lost in history. Some of the symbols appear in Greek horoscopes which are about 2,000 years old, some of them seem to be alchemical signs, and some of them relate to the shape of the constellations themselves.

Aries the Ram

The symbol for Aries can be described as resembling the face and horns of a goat or ram, or the eyebrows and nose of the face, which are said to be prominent in Aries people. Alternatively, this symbol is similar to that of a plant shoot when it first emerges from the ground in the spring.

Taurus the Bull

The symbol for Taurus has been described as the head of a bull, again with horns. It has also been described as the Moon resting on the Sun. Compared with the symbol for Aries, it has a nice, solid, round shape.

Gemini the Twins

Gemini's symbol is based on the twin stars Castor and Pollux in the constellation of Gemini. It is literally the Roman numeral II, and the theme of duality is the key to the meaning of this sign.

Cancer the Crab

The symbol for Cancer is circular, internal and protective. It has been described as symbolising the ovaries, the breasts, and the closeness of the mother-child relationship, reflecting the nurturing quality of this sign.

Leo the Lion

The symbol for Leo is similar to the stars in the constellation of Leo. It has also been described as the head and mane of a lion.

Virgo the Virgin

See the description for Scorpio, below.

Libra the Scales

The sign of Libra was a later addition to the zodiac, being placed between the signs of Virgo and Scorpio, 'borrowing' the claws of Scorpio to form the scales of Libra. It has been described as a dairy maid's yoke, used to balance two pales of milk. It has also been described as a symbol of the Sun setting over the western horizon, since Libra is also associated with the western side of the horoscope.

Scorpio the Scorpion

The symbols for Virgo and Scorpio are remarkably similar, since they are both created from an identical 'm' - an ancient medical symbol. Both Virgo and Scorpio are associated with medicine and healing. The two constellations of Virgo and Scorpio are extremely large and easily identifiable in the night sky. The enclosed shape in the symbol for Virgo and the 'sting' in the scorpion's tale have been described as the feminine and masculine versions of the same symbol.

Sagittarius the Archer

The glyph for Sagittarius is also similar to the constellation, with the archer's arrow pointing upwards ready to be shot into the sky. The line across the arrow is said to symbolise the fact that Sagittarius is a centaur, half human and half horse.

Capricorn the Goat

The symbol for Capricorn contains the v-shape of the goat's head and the fish tale of the sea-goat, since the constellation of Capricorn is found in the 'southern seas' of the celestial sphere. Alternatively, it has also been described as the goat bending down on its knees.

Aquarius the Water-Bearer

The symbol for Aquarius describes air waves or radio waves, and particularly relates to the travelling of information through the air.

Pisces the Fish

Pisces is the symbol of two fish or dolphins yoked together.

Zodiac signs versus constellations

It is worth knowing at this stage that the twelve zodiac signs are not the same thing as the twelve constellations (or star groups). As we have seen above, the signs of the zodiac are twelve equal 30º sections of the ecliptic, related to the seasonal year and anchored to the four cardinal points of the Sun's annual journey. Western astrology, which is based on the seasonal year, uses the tropical or seasonal zodiac. Indian or Vedic astrology uses the sidereal (or 'star') zodiac, based on the positions of the stars in the actual constellations, which are star groups of very different sizes. Owing to a phenomenon caused by the earth's 'wobble' on its axis, the two zodiacs have gradually, over the last two thousand years or so, started to drift out of alignment with each other.

Audience: Can you say more about this? I am not sure that I understand.

Clare: Perhaps the best way to imagine this is as two concentric circles, the outer circle representing the backdrop of the stars, containing the twelve constellations, and the inner circle divided into the twelve signs of the zodiac, each 30º in length. Approximately 2000 years ago these two circles lined up, with the beginning of the constellation of Aries and the beginning of the zodiac sign of Aries in the same place. Since that time, these two circles have been moving in opposite directions at the rate of 1º every 72 years. They will not line up again for approximately 26,000 years. This 26,000-year cycle has itself been divided into twelve 'astrological ages' of approximately 2,000 years each.

For the last two thousand years, at the spring equinox the Sun has in fact been rising against the constellation of Pisces and will gradually begin to rise against the constellation of Aquarius, heralding the start of the new astrological age referred to in the 1960s musical Hair as the dawn of the Age of Aquarius. In another 2,000 years, when the Sun begins to rise against the constellation of Capricorn, we will enter a new 'Age of Capricorn', which doesn't have quite the same ring to it. The astrological ages have their own meanings too, although these are on a quite different scale. Western astrology uses the tropical zodiac as its primary frame of reference, and eastern, Indian or Vedic astrology uses the sidereal zodiac as its primary frame of reference. The difference between the two zodiacs is now approximately 26º.

Audience: Does that mean that my Sun could be in the previous sign in sidereal astrology?

Clare: Yes, if your Sun is between 0º and 25º of a sign. Rather than letting this bother us too much, I think we need to appreciate that every culture has its own sky lore and its own astrology, which is an expression of the history, mythology, religion and philosophy of the culture in which it has developed. As a broad generalisation, we can say that the western tropical zodiac is solar because we use a solar calendar. This reflects the emphasis in western cultures on self-sufficiency, self-expression and the development of the individual. The eastern sidereal zodiac, on the other hand, belongs to cultures where the Moon is the basis of the calendar and of the annual festivals. Eastern astrology is not so focused on the development of the individual but puts the emphasis on community and family and tends to take a more fated approach than western psychological astrology. You will have experienced this for yourselves if you have ever had your chart done in India. It is a much more fated kind of astrology.

"Mapping the Psyche"