A birth chart (also called a natal chart) is a map of the sky at the exact moment and place you were born, drawn as a circle. Every planet gets a position on that circle, measured in degrees along the zodiac. Astrology then reads those positions as a portrait of a person. The map itself is astronomy; the reading is tradition.
What you need to make one
- Date of birth. Enough for the Sun, the planets and usually the Moon.
- Time of birth, ideally to the minute. It fixes the rising sign and the houses, and it settles the Moon’s sign on days when the Moon changes sign.
- Place of birth. It sets the time zone and the horizon.
The three big ones
The Sun sign
Where the Sun was along the zodiac. This is the sign people mean when they ask “what’s your sign”. It moves one sign a month, so almost everyone knows theirs. In a reading it stands for the core of who you are becoming.
The Moon sign
Where the Moon was. The Moon moves a sign every two and a half days, so this needs the date and is sharpened by the time. It stands for how you feel and what you need.
The rising sign (ascendant)
The sign that was coming up over the eastern horizon at the moment of birth. It changes roughly every two hours, which is why the birth time matters. It stands for the first impression you make, the door you come through.
The planets
Mercury (how you think and speak), Venus (how you love and what you find beautiful), Mars (how you act and what you want), Jupiter (where you grow and get lucky), Saturn (where you are tested and build), and the slow outer three, Uranus, Neptune and Pluto, which describe a generation more than a person.
Houses
With a birth time the circle is also divided into twelve houses, counted from the rising sign: self, money, words, home, joy, work, partners, shared things, horizons, calling, friends, and the inner life. A planet’s house says where in life its theme plays out. Without a time, many readings count houses from the Sun sign instead (solar houses), the method used in sun-sign astrology.
Elements and modes
Each sign belongs to an element (fire, earth, air, water) and a mode (cardinal, fixed, mutable). Counting how many planets sit in each element is a quick way to see the weather of a chart: a lot of water and little air, say, is a person who feels first and explains later.
What a birth chart does not do
It does not predict events, and it is not a verdict on anyone. The astronomy is exact; the meanings are a language people have used for a long time to think about themselves. Read it the way you would read a good description of yourself by a friend: take what fits, leave what does not.
Read yours as a story
The Night You Were Born calculates your chart on your own device and reads it in eight illustrated chapters, with or without a birth time. Get it on Etsy.