Astrology aspects for beginners
The opposition
The opposition is the aspect of 180 degrees, half the circle, the full face. Two planets stand in opposite signs, or within orb of that axis. At a Full Moon the Sun and Moon are in opposition, which is why the Moon's whole earthward face is lit. The aspect is a major hard aspect. Its difficulty is not the square's grinding right angle. Its difficulty is polarity. Each planet sees the other at the greatest distance, and neither can pretend the other is a private mood.
Opposite signs share a modality and a polarity, and they split the element. Aries opposes Libra: cardinal fire against cardinal air, self and other, the ram and the scales. Taurus opposes Scorpio: fixed earth and fixed water, having and sharing. Gemini opposes Sagittarius: the near fact and the far aim. Cancer opposes Capricorn: private root and public structure. Leo opposes Aquarius: the heart and the circle. Virgo opposes Pisces: the sorted part and the unbounded whole. Learn the six pairs. Most opposition readings are a variation on one of them, plus the planets that happen to be standing there.
The opposition gives awareness through an other. Sometimes the other is a person, especially when the axis is the first house and the seventh. Sometimes the other is a rival topic inside one life: the career and the home, the speech and the belief. The chart shows a face-off. The work is being able to look at both faces.
Orbs for the opposition are traditionally wide, similar to the trine and the conjunction. An exact opposition is unmistakable, a Full Moon kind of clarity in whatever topics are involved. A wide opposition is a background polarity. Out-of-sign oppositions, planets 180 degrees apart but not in opposite signs, are a later or a more degree-driven claim. The sign pair is the part a beginner should be able to say aloud.
Applying oppositions build toward a culmination. Separating oppositions are the light after the full phase, a polarity the chart has already survived and still carries. In natal work, both are structure. People often meet an applying opposition between slow planets as a chapter of adulthood, and a luminary opposition as a theme they have known since childhood. The transiting opposition of a slow planet to a natal planet is a season of that same full-face clarity. It is a season, not a verdict.
Reception and dignity change the manners of the face-off. The Moon opposite Saturn is a classic tension of need and limit. If Saturn is in his domicile and the Moon is in her fall, the limit has the stronger traditional footing, and the reading should say so without cruelty. If the Moon is exalted and Saturn is in fall, the need has the stronger footing. The aspect is the same geometry. The dignities say who is equipped for the weather.
Oppositions want a witness. Libra's scales are the emblem of the Aries axis and a fair emblem for the aspect as a whole: a beam that holds two real weights. Let each planet keep its topic.
In practice, name the pair of signs, name the two planets, and ask who or what is holding the far end. For the fusion at zero degrees, read the conjunction. For the right angle, read the square. For the horizon itself, read the first house and the seventh.