Astrology basics 02
The parts of a birth chart
Signs, houses, aspects and points: the four things every chart is built from.
Every birth chart is built from the same parts: Sun, Moon and planets, the twelve signs, the twelve houses, the aspects between them, and some other important points. Every chart is a unique combination of all these parts.
The signs
A birth chart is, at heart, a two-dimensional chart showing the positions of the planets and other points on the zodiac circle, which is made of twelve signs.
Every zodiac sign carries one of two polarities (positive, negative), one of three qualities (cardinal, fixed, mutable) and one of four elements (fire, earth, air, water). So each sign is a unique combination of its own.
- Aries positive, cardinal, fire
- Taurus negative, fixed, earth
- Gemini positive, mutable, air
- Cancer negative, cardinal, water
- Leo positive, fixed, fire
- Virgo negative, mutable, earth
- Libra positive, cardinal, air
- Scorpio negative, fixed, water
- Sagittarius positive, mutable, fire
- Capricorn negative, cardinal, earth
- Aquarius positive, fixed, air
- Pisces negative, mutable, water
The houses
The circle is divided a second time, into twelve houses. Where they begin is set by the Ascendant, the point that was rising in the east at the moment you were born.
Each house stands for one area of life. Some houses hold planets, and a planet in a house gives that area more weight and its own colour. The houses have a chapter of their own.
The aspects
Every one of these positions is calculated astronomically and drawn on the circle, and between them are angles. Some of those angles, the aspects, matter a great deal: they colour, for instance, how a planet in its sign is read. More in Aspects.
The three points that count most
The most important points in a personal horoscope are the Sun, the Moon and the Ascendant, and they are given special emphasis in the analysis. We are particularly interested in which sign and house they are in, and in all the aspects they form with other points.
- Sun your self, your will, how you shine
- Moon feelings, moods, instinct
- Ascendant how you come across, and how you begin
The personal planets
Four more planets matter a great deal in reading a chart: Mercury, Venus, Mars and Jupiter. Each one describes one part of your personality.
The generation planets
Saturn, Uranus, Neptune and Pluto travel very slowly, and are called the generation planets. Neptune and Pluto keep whole generations in the same sign, so the sign they are in says little about one person. But it counts if they sit on one of the important points, which aspects they make and which houses they are in.
Both groups are in The Sun, the Moon and the planets.
Other points
Beside the planets and the houses, a reading uses a few more points: two Arabic parts, the Part of Spirit and the Part of Fortune; the North Node; the culminating planet; the rising planet; and any planet in domicile. Read more about important points in the last chapter.
Your birth chart reading
Your whole chart, read in one book
The book goes through every planet, every house and every aspect in one birth chart, the way these pages explain them, but about you.
Marsa wrote every word. Your chart decides which of them you get.
See the books →See it in your own birth chart
Enter your birth details and we calculate your chart precisely, with every planet this guide describes in the sign and house where it stood. You get the chart wheel and a short reading as a PDF, by email.
It is free, and there is nothing to pay at any point.
Five details, and the birth chart is yours. If you do not know the exact time of birth, that is fine — the link below sets it to the standard value.