What do the twelve zodiac signs mean?

By Ines Vasquez

The twelve signs are equal 30-degree divisions of the ecliptic, the sun's apparent yearly path around the sky. Each is read as a quality — a style of doing something rather than a thing done. Modern astrology treats a sign as a personality type. The older tradition treated it as a condition a planet is in. Both readings are still in circulation.

What do the twelve zodiac signs mean?

Each sign names a manner: a way energy tends to move, not a set of events. Aries is read as fast and initiating, Taurus as slow and retaining, and so on through the circle. What varies between schools of astrology is whose manner it describes. In sun-sign astrology, which is roughly a century old, the sign describes the person. In the older tradition, running from the Hellenistic astrologers through to the seventeenth century, the sign describes the planet sitting in it — Mars in Cancer behaves like Mars under water, cautious and indirect, while Mars in Aries behaves like Mars at home. The sign was an adverb before it was a noun.

What is a zodiac sign, actually?

A sign is a 30-degree slice of a 360-degree circle. The circle is the ecliptic, which is the plane of the earth's orbit projected onto the sky, and from the ground it looks like the path the sun walks through the year. Divide that path into twelve equal parts and you have the signs.

The zero point of the circle, in the tropical zodiac used by almost all Western astrologers, is the March equinox — the moment the sun crosses the celestial equator going north. Zero degrees of Aries is that crossing, by definition. The signs are therefore anchored to the seasons rather than to any group of stars, which is why sun-sign dates are stable from year to year, shifting by a day at most.

Are the signs the same as the constellations?

No. The constellations are irregular patterns of actual stars, of wildly different sizes; the signs are twelve equal mathematical divisions. They shared names and once roughly shared positions, but the earth's axis wobbles, completing a slow cone roughly every 26,000 years. Hipparchus noticed this drift around 130 BC and it is called the precession of the equinoxes. Over two thousand years it has pulled the tropical signs about one whole sign away from their namesake constellations.

Indian astrology and a minority of Western astrologers use a sidereal zodiac instead, which stays fixed to the stars and so gives most people a sun one sign earlier. Neither system is an error. They are measuring different things: the tropical zodiac measures the sun's relationship to the seasons, the sidereal zodiac its relationship to the fixed stars.

Did the old astrologers read signs as personality types?

Not primarily. Vettius Valens, writing around 150 AD, and Ptolemy in the Tetrabiblos in the second century, use the signs mainly as modifiers — a sign gives a planet its temperature and moisture, tells you whether the planet is in its own domicile or in exile, and conditions how that planet will act. Character came from the whole configuration, with particular weight on the Ascendant, the Moon and the chart's overall ruler. The sun's sign was one factor among many.

Reading a person as "a Taurus" is a twentieth-century development. Alan Leo, in the decades either side of 1900, simplified astrology for a mass readership and put the sun at the centre of character. R. H. Naylor's newspaper column, which began in the Sunday Express in 1930, fixed sun signs in popular culture, and Linda Goodman's Sun Signs in 1968 gave them their modern vocabulary. The psychological turn — signs as types of psyche rather than types of weather — comes mostly from Dane Rudhyar in the 1930s and the Jungian astrologers after him.

Neither reading cancels the other. But a page that offers you a sign's "personality" without saying that this framing is about a hundred years old is leaving out the one fact that explains why the older books sound so different.

What are the twelve signs, with their elements, modalities and rulers?

Sign Dates (approx.) Element Modality Traditional ruler Modern ruler
Aries 21 Mar – 19 Apr Fire Cardinal Mars Mars
Taurus 20 Apr – 20 May Earth Fixed Venus Venus
Gemini 21 May – 20 Jun Air Mutable Mercury Mercury
Cancer 21 Jun – 22 Jul Water Cardinal Moon Moon
Leo 23 Jul – 22 Aug Fire Fixed Sun Sun
Virgo 23 Aug – 22 Sep Earth Mutable Mercury Mercury
Libra 23 Sep – 22 Oct Air Cardinal Venus Venus
Scorpio 23 Oct – 21 Nov Water Fixed Mars Pluto
Sagittarius 22 Nov – 21 Dec Fire Mutable Jupiter Jupiter
Capricorn 22 Dec – 19 Jan Earth Cardinal Saturn Saturn
Aquarius 20 Jan – 18 Feb Air Fixed Saturn Uranus
Pisces 19 Feb – 20 Mar Water Mutable Jupiter Neptune

Dates move by a day either way depending on the year and the time zone, because the equinox does not fall at the same clock moment annually. Anyone born within a day of a boundary needs the chart calculated rather than assumed. The element and modality columns are not decoration: the four elements and the three modalities together generate the twelve, since each element appears once in each modality and no two signs share both.

What does each of the twelve signs mean?

Aries. Cardinal fire, ruled by Mars, and read as the impulse to begin: directness, appetite, a short fuse between wanting and doing. Classical sources call it hot and dry. The difficulty the tradition names is that starting and finishing are separate skills, and Aries is credited with only the first.

Taurus. Fixed earth and one of Venus's two homes, read as steadiness, physical appetite, and a strong attachment to what is already in hand. The older texts associate it with fertility and accumulation.

Gemini. Mutable air, Mercury's day home, and read as plurality — two of everything, including minds about a decision. The tradition gives it quickness, facility with language, an interest in the next thing. What it is said to cost is depth: the classical complaint about Gemini is not shallowness of feeling but a reluctance to stay long enough with one object to exhaust it.

Cancer. Cardinal water and the Moon's only domicile, which makes it the most changeable of the four cardinal signs: protective, retentive, organised around what it does not want to lose. The named difficulty is that it keeps things past their usefulness, including grievances.

Leo. Fixed fire and the Sun's single home, read as warmth, generosity and the wish to be visible doing something worth seeing.

Virgo. Here the ancient and modern readings genuinely part company. Modern astrology gives Virgo the anxious perfectionist, the health-conscious editor, the one who notices the error — a reading that arrived largely through the twentieth-century habit of equating each sign with the matching house, so Virgo inherited the sixth house's territory of work, service and illness. Valens does not describe Virgo natives at all in those terms. His entry for the sign is a list of technical attributes — feminine, bicorporeal, earthy, barren — and the learning and love of enquiry that modern descriptions attach to Virgo belong, in his text, to Mercury. Mercury's nocturnal domicile, earth rather than air, is better read as applied intelligence than as fussiness.

Libra. The last of the twelve to be named: Greek astronomers called this stretch of sky the Claws, borrowing it from Scorpio, and the Scales are a Babylonian image that the Latin world made standard. Venus's other home, cardinal air, read as the sign most concerned with the space between two people — comparison, fairness, the weighing itself. Deferral is the cost usually named, since scales that keep adjusting never settle.

Scorpio. Fixed water. Traditional astrologers give it to Mars and read it as Mars submerged — pressure that does not vent. Modern astrologers give it to Pluto, assigned after Pluto's discovery in 1930, and read it as depth, crisis and transformation. Both rulerships are in active use and they produce noticeably different readings.

Sagittarius. Mutable fire, Jupiter's day home, read as the appetite for more horizon: travel, belief, the long view. Overshooting is the classical complaint.

Capricorn. The drawback first, since the tradition names it readily: coldness, a tendency to treat people as functions, difficulty resting. Saturn's domicile in cardinal earth is otherwise read as endurance, realism about time, and the willingness to do unglamorous work for a result that is years away.

Aquarius. Fixed air and Saturn's other home, which is why the older reading is colder than the modern one — detachment, principle, a certain immovability — while modern astrology, handing it to Uranus after 1781, emphasises invention and dissent instead. What survives both readings is the preference for the group over the pair, and for the idea over the instance.

Pisces. Mutable water, Jupiter's night home. Read as permeability: the sign with the least defined edge, which the tradition treats as both its gift and its problem, since what comes in easily includes things better kept out.

Why is your sun sign only part of the chart?

Because the sun is one of roughly ten bodies, and the sign it occupies tells you nothing about where it sits in the day. Two people born the same date twelve hours apart share every planetary sign placement bar, often, the Moon — and share almost nothing of the chart’s structure, because the Ascendant — the degree of the ecliptic rising over the eastern horizon, which moves about a degree every four minutes and through a whole sign in roughly two hours — will be on the far side of the chart. The Ascendant is what determines the houses, and the houses are what attach a planet to an area of life rather than leaving it as a free-floating quality.

Sign, house and aspect are three separate layers. A sign says how, a house says where, an aspect says what else is involved. Sun, Moon and rising together are the usual starting point for a reason, and transits — the planets' current positions measured against the birth chart — are a different question again.

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