Libra (♎) — Cardinal Air, The Harmonizer

Libra spans 180-210 degrees as the cardinal air sign, ruled by Venus. It marks the autumnal equinox — the point of exact balance between day and night — and governs the seventh house of partnership, contracts, and open enemies. In the Tetrabiblos, Ptolemy classifies Libra as hot and moist, emphasizing its social and relational orientation. The Scales are the only inanimate symbol in the zodiac, reflecting Libra's concern with abstract principles of justice, proportion, and aesthetic harmony; Cafe Astrology identifies its cardinal drive as the active pursuit of equilibrium in relationship.