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The 12 zodiac signs at a glance

tl;dr
  • Twelve signs split the tropical zodiac into 30° each, anchored to the seasons, not the constellations.
  • Each sign has a fixed element (fire, earth, air, water), a modality (cardinal, fixed, mutable) and a ruling planet.
  • Dates shift by a day year to year because the Sun's ingress is an astronomical instant, not a calendar rule.

All twelve signs

SignGlyphDates (approx.)ElementModalityRuling planetSymbol
AriesMar 21 – Apr 19FireCardinalMarsRam
TaurusApr 20 – May 20EarthFixedVenusBull
GeminiMay 21 – Jun 20AirMutableMercuryTwins
CancerJun 21 – Jul 22WaterCardinalMoonCrab
LeoJul 23 – Aug 22FireFixedSunLion
VirgoAug 23 – Sep 22EarthMutableMercuryMaiden
LibraSep 23 – Oct 22AirCardinalVenusScales
ScorpioOct 23 – Nov 21WaterFixedMars (Pluto, modern)Scorpion
SagittariusNov 22 – Dec 21FireMutableJupiterArcher
CapricornDec 22 – Jan 19EarthCardinalSaturnSea-Goat
AquariusJan 20 – Feb 18AirFixedSaturn (Uranus, modern)Water Bearer
PiscesFeb 19 – Mar 20WaterMutableJupiter (Neptune, modern)Fishes

How the four elements and three modalities map

The four elements repeat in the same order around the wheel: fire, earth, air, water, starting at Aries. Signs sharing an element sit 120° apart and form a triangle, called a trigon.

The three modalities also repeat — cardinal, fixed, mutable — starting at Aries. Cardinal signs open each season (Aries/spring, Cancer/summer, Libra/autumn, Capricorn/winter in the northern hemisphere), fixed signs hold its middle, and mutable signs transition out of it.

Because every sign has exactly one element and one modality, the pair is unique: there is only one cardinal-fire sign (Aries), one fixed-earth sign (Taurus), and so on.

Classical vs modern rulers

Before the outer planets were discovered, each of the seven classical planets ruled either one or two signs, with the Sun and Moon ruling one each. That scheme is still used in traditional and Hellenistic astrology.

Modern Western astrology reassigned Scorpio to Pluto, Aquarius to Uranus, and Pisces to Neptune after those planets were found (1781–1930). Both rulers are shown above so the table is usable in either tradition.

Full sign-by-sign reference on astro.otldr.com