Planets, signs and houses
A birth chart has three main building blocks. A simple way to remember them:
- Planets are the "what": different drives, such as Venus for love and Mars for action.
- Signs are the "how": the style a planet expresses itself in, such as fiery Aries or careful Virgo.
- Houses are the "where": the area of life where that energy shows up, such as home, work or friendships.
So Venus in Gemini in the tenth house might be read as a love of conversation and variety (Venus in Gemini) showing up in your career and public life (tenth house).
What exactly is a house?
The signs are fixed to the sky (or the seasons) and move across the sky every day as the Earth turns. The houses are fixed to the place where you were born. They divide the sky around that spot into twelve sections, using the horizon and the meridian (the line running overhead from north to south).
Two key points anchor the houses:
- The ascendant, or rising sign: the point of the zodiac rising over the eastern horizon at your birth. It begins the first house.
- The midheaven: the highest point of the zodiac in the sky at your birth. In many house systems it begins the tenth house.
Because the Earth spins once a day, all twelve signs pass over the horizon in about 24 hours. The ascendant moves about one degree every four minutes on average. This is why the houses need an accurate birth time, while planet signs usually do not.
The twelve houses
These are the traditional themes. Different schools stress different parts, but this is the broad picture.
1st house: self
Your body, appearance, first impressions and general approach to life. It is the house of the rising sign.
2nd house: resources
Money, possessions, what you value and your sense of self-worth.
3rd house: communication
Everyday talk, writing, learning, siblings, neighbours and short trips.
4th house: home and roots
Family, home, your background and your private inner life. It sits at the bottom of the chart.
5th house: joy
Creativity, play, romance, hobbies and children.
6th house: daily life
Work routines, habits, health habits, service and pets.
7th house: partnership
Marriage, close partners, business partners and open rivals. It sits opposite the first house: self and other.
8th house: shared and hidden
Shared money, debts, inheritance, intimacy, endings and deep change.
9th house: horizons
Travel, higher learning, beliefs, philosophy and long journeys of the mind.
10th house: career and reputation
Your public role, ambitions, achievements and how the world sees you.
11th house: community
Friends, groups, networks, hopes and plans for the future.
12th house: the unseen
Rest, solitude, the subconscious, endings, and things done behind the scenes.
Angular, succedent and cadent houses
Astrologers often group the houses into three types:
- Angular houses (1, 4, 7, 10) begin at the four main angles of the chart. Planets here are traditionally thought to be strong and visible.
- Succedent houses (2, 5, 8, 11) follow them and are linked to stability and resources.
- Cadent houses (3, 6, 9, 12) come before the next angle and are linked to learning, adjusting and change.
House systems: why charts differ
Dividing a curved sky into twelve parts is a geometry problem, and astrologers have solved it in different ways. The main systems are:
- Whole Sign houses. The oldest known system, used in Hellenistic astrology about 2,000 years ago and still standard in Vedic astrology. The whole sign containing the ascendant becomes the first house, the next sign the second house, and so on. Simple and clear.
- Equal houses. Each house is exactly 30 degrees, starting from the exact degree of the ascendant.
- Placidus. Named after the 17th century monk Placidus de Titis. It divides the sky by time, so houses can be uneven in size. It is the most common system in modern Western astrology. At very high latitudes, near the Arctic and Antarctic circles, it stops working properly.
- Others, such as Koch, Porphyry and Regiomontanus, use different geometric methods.
Because of these differences, a planet near the edge of a house may fall in one house in Placidus and the next house in Whole Sign. Neither is the "real" answer. They are different conventions. A good chart tells you which one it used.
Why your birth time matters
If your birth time is off by even 15 to 30 minutes, the ascendant can move several degrees, and planets near house edges can change houses. If you do not know your birth time at all, the houses cannot be calculated reliably. Some astrologers then use a "solar chart", which puts the Sun's sign in the first house, as a symbolic stand-in.
Birth certificates and hospital records are usually the best sources. Family memories ("it was just after lunch") are a useful start, but often rounded.
Empty houses
With ten or so planets and twelve houses, some houses will always be empty. That does not mean that area of life is missing or unlucky. Astrologers look at the sign on the house cusp (its starting edge) and the planet that rules that sign to describe it.
What the houses are and are not
The houses are a symbolic map. They are a way of organising life into areas so you can think about each one. They are not physical regions of space that send out influences, and there is no scientific evidence that a planet's house placement shapes events in your life. Many people still find them a useful framework for reflecting on where their energy goes.
Try it
Our birth chart calculator places every planet in its house and names the house system it used. To see which houses current planets are moving through, try the transit storyteller.