Astrology houses: what each one means and how they're drawn

Signs say how, houses say where

A planet's sign describes its style: Mars in Aries charges, Mars in Libra negotiates. Its house says which part of life that energy goes into: work, home, love, money, friends. The twelve houses divide the sky as seen from your birthplace at your birth time, starting from the eastern horizon (the ascendant) and running anticlockwise round the wheel.

That's why houses need a birth time and place. The signs are the same for everyone on Earth at a given moment; the houses depend on where you were standing and the minute you arrived.

The twelve, briefly

Four cusps carry extra weight. The 1st is the ascendant, the 4th the lowest point of the chart (home and roots), the 7th the descendant (partners), and the 10th, in most systems, the Midheaven (career and reputation). Planets near these angles tend to be loud in a chart.

Why there are several house systems

Dividing a sphere into twelve sounds simple until you try it. The ecliptic (the Sun's path, where the signs are) is tilted against the equator and against your horizon, so "equal parts" can mean equal parts of the ecliptic, of time, or of space, and each gives different lines. The common choices:

• Placidus divides the time each degree takes to travel from the horizon to the meridian into thirds. It's the most used system in modern Western astrology and our default. It can't be drawn above the polar circles, where some degrees never rise.
• Whole sign makes the entire rising sign the 1st house, the next sign the 2nd, and so on. It's the oldest system and has come back into fashion; houses always line up with signs.
• Equal starts at the ascendant degree and marks a cusp every 30°.
• Porphyry splits each quarter of the chart (between the angles) into three equal parts. It works at any latitude, which is why we fall back to it near the poles.

One chart, four systems

Here are the cusps for someone born on 4 August 1990 at 7:20pm in Chicago, worked out in each system:

The 1st house cusp is the same in Placidus, Equal and Porphyry (it's the ascendant), while Whole sign starts it at 0° of the rising sign. The middle cusps drift apart, sometimes by many degrees. In this chart that moves the Moon: it lands in the 12th (Placidus), 1st (Whole sign), 12th (Equal), 12th (Porphyry).

Which is right? Astrologers argue about it, and there's no experiment that settles it. A reasonable approach is to start with Placidus, then look at Whole sign, and notice which reading fits your life. Every chart you save in Charthood can switch between all four.