In astrology, the 7th house is the realm of partnership — marriage, business partners, open enemies, and the qualities you project onto others. It's also the house most directly related to your relationship patterns. The 7th house cusp is called the Descendant — the point on the western horizon where the sky met the earth at the moment of your birth.
The 7th house begins at the Descendant — the exact opposite point from your Ascendant (rising sign). If your Ascendant is Aries, your Descendant is Libra, and your 7th house begins there. Because Ascendant changes every two hours, the 7th house cusp is highly time-sensitive. Two people born on the same day three hours apart may have entirely different 7th houses.
In the Placidus system (the most common in modern Western astrology), the 7th house spans an arc determined by the latitude and time of birth, not a fixed 30 degrees.
A planet placed in your natal 7th house describes a quality you frequently encounter in partners and project onto others. Venus in the 7th house draws partners who embody beauty, harmony, or financial stability — and tends to idealize relationships.
Mars in the 7th house attracts or unconsciously generates conflict in partnerships. Saturn in the 7th house makes relationships feel weighty, slow to form, and often involves age or authority differentials. Moon in the 7th house seeks emotional caretaking in partners; familiarity registers as recognition.
These are archetypal patterns — the specific texture depends on the planet's sign, aspects, and the chart as a whole.
The planet that rules the sign on your 7th house cusp (the 'ruler of the 7th') describes the deeper structure of your partnership patterns. If your 7th house is Libra, Venus is your 7th house ruler — and where Venus sits in your chart describes where you find or lose love. This is one of the most analytically rich points in any chart — and a primary diagnostic tool for understanding why certain patterns repeat.