Libra
Libra is cardinal air, the sign of the September equinox, when day and night balance again and the northern year tips toward dark. The image is the scales. A scale is a tool, not a mood. It compares two weights and tells you which way the beam tilts. Cardinal signs begin. Air signs begin in relationship and in ideas. Libra begins a pairing: a treaty, a conversation that has two real sides, an aesthetic choice that considers the whole room.
The weather is proportional. It wants a fair arrangement, a beautiful one if beauty can be had without a lie, and a decision that can be shown to the other person. Classical hot and moist air is social heat. In Libra that heat is aimed at the bond. The sign can delay, because a scale that rushes is not a scale. The delay is part of the method. It becomes a problem only when the beam never settles.
Venus rules Libra, and she also rules Taurus. In Libra, Venus is in her air domicile: worth, affection, and grace expressed as an agreement between people, or as a composition the eye can judge. Saturn is exalted in Libra, classically near 21 degrees. The planet of limit is an honored guest in the sign of the contract. A bond with a boundary, a peace that has terms, a beauty that can bear weight: that is the dignity. The Sun is in fall in Libra, opposite his exaltation in Aries. The single radiant will fits this weather poorly, because the sign keeps asking what the other side of the scale is doing. Mars is in detriment in Libra, opposite his domicile in Aries. Open conflict is a bad fit for a sign trying to set the beam level. Mars can still act, usually by choosing a side and keeping the choice clean.
The natural house is the seventh: the partner, the open opponent, the contract, the person across the table. It is an angular house, as structurally important as the first. A planet in the sign of Libra brings a pairing style into whatever house it occupies. Libra on the seventh is the natural match. Libra on the first describes a person who meets the world already considering the other, and that rising sign needs a birth time.
Sun in Libra makes the conscious will diplomatic and sensitive to dissonance. The person often finds themselves through a relationship or a craft of balance, and they can lose the thread when they perform agreement they do not feel. Moon in Libra feels safer when the room is fair and the tone is kind, and feeling may wait for the other person's face before it knows its own. Venus in Libra is the ruler at home. The Ascendant in Libra makes an entrance that seeks rapport.
Libra squares Cancer and Capricorn, and it opposes Aries. The opposition is the pair of the other and the self, the scales and the ram. Trines run to Gemini and Aquarius. Air talks to air, and the social craft comes easily. The risk is a grace that never decides, a scale kept in motion so that no weight has to be refused.
In a reading, ask who the other is, and what the terms are. Libra's gift is a beginning made of two. Its risk is a beginning that belongs to neither person because both were being polite. For the ruler, read Venus. For the exaltation, read Saturn. For the partner and the open other, read the seventh house.