In astrology, the zodiac is divided into twelve equal signs. A sign names a sector of the chosen zodiac and supplies a symbolic style for anything placed there. It is not the same thing as a constellation, and a sign keyword is not a personality diagnosis.
Two organizing patterns
Astrological tradition groups signs by element and modality. Elements describe a broad mode of expression; modalities describe how a sign is said to begin, sustain, or adapt activity.
| Sign | Element | Modality | A neutral prompt |
|---|---|---|---|
| Aries | Fire | Cardinal | What is ready to begin? |
| Taurus | Earth | Fixed | What is worth sustaining? |
| Gemini | Air | Mutable | What needs another perspective? |
| Cancer | Water | Cardinal | What needs care or protection? |
| Leo | Fire | Fixed | What deserves wholehearted expression? |
| Virgo | Earth | Mutable | What can be refined in practice? |
| Libra | Air | Cardinal | What would make the exchange fairer? |
| Scorpio | Water | Fixed | What requires depth and commitment? |
| Sagittarius | Fire | Mutable | What wider context changes the question? |
| Capricorn | Earth | Cardinal | What structure would support the aim? |
| Aquarius | Air | Fixed | What pattern could be reconsidered? |
| Pisces | Water | Mutable | Where are boundaries or empathy needed? |
The prompts are examples of reflective use, not claims that everyone with a placement in that sign will behave the same way.
Signs modify chart functions
A sign gains context from what occupies it. Mars in a sign is traditionally read as a style of effort; the Moon in the same sign is read through habits and needs. This is why “I am a Leo” gives less information than “my Sun is in Leo,” and why a whole chart cannot be reduced to one sign.
Sign, constellation, and season
Named constellations have irregular observed boundaries. Zodiac signs are defined sectors in a chosen system. The tropical zodiac anchors its cycle to seasonal points; sidereal approaches use a stellar reference and an offset convention. A page should state which system it uses.
Common mistakes
- Ranking signs as good, bad, strong, or weak people.
- Treating element and modality labels as test results.
- Mixing tropical and sidereal positions without saying so.
- Copying one keyword across the Sun, Moon, planets, and angles without considering their roles.
Next, use how to read a birth chart to place signs in context, and consult element and modality for the two grouping systems.
Sources and further reading
The project methodology documents the tropical-zodiac and coordinate conventions, while the pinned Astronomy Engine JavaScript reference documents the longitude calculation used by the project. Neither source assigns personality traits to signs; the element, modality, and prompt vocabulary above is identified as astrological tradition.