Opposition
Aspect Degree: 180
Degree Orbs: 6-10°
Glyph: ☍
Description:
The opposition is formed when two planets are directly across from each other at 180 degrees. It is considered a major dynamic aspects, characterized by tension, duality, and relational pull. Oppositions reflect a polarity in consciousness — where two forces mirror, reflect, or challenge each other across a divide.
This aspect reveals area of life where projection mirroring, and inner conflict are likely. Though oppositions can bring stress, they also offer potential for balance, awareness, and/or integration through contrast. Growth often comes by learning to hold two opposing truths or desires simultaneously, without collapsing into either side.
Key Points:
- Indicates duality and tension between planetary energies.
- Can. Reflect projection of traits onto others or the outside world.
- Offers a path to balance, awareness, and/or relational maturity.
- Shows where growth happens by holding opposing forces in conscious dialogue.
Example interpretations:
Sun opposing Moon: Identity vs. emotional needs: tension between self-expression and belonging.
Mars opposite Neptune: Drive vs. surrender; direct action challenged by blurred motivation or spiritual diffusion.
Mercury in opposition with Uranus: Thought vs. revelation; tension between rationality and intuition, stability and insight.
Use in Practice:
Oppositions are often seen in relationships, life lessons, and developmental arcs that require integration. In a birth chart, they highlight internal or external confrontations that are meant to bring clarity through reflection. In energetic or magical practice, opposition aspects may call for shadow work, mirror rituals, or polarity healing. They’re a call to recognize what we resist, disown, or externalize — and to bring that energy home with awareness, compassio0n, and/or conscious alignment.
aspects/major
🧮 Aspect Arithmetic
| Quantity | Value |
|---|---|
| Exact angle | 180.000000° = 180°00′00.0″ |
| Formula | 360° × 1/2 |
| Harmonic number | H2 |
| Fraction of circle | 1/2 |
| Shortest-arc separation | 180.000000° |
| Explement (360° − angle) | 180.000000° |
| Orb (this vault) | 6–10° (author); traditional: sum of moieties |
| Family | Major (Ptolemaic) aspects — harmonics 1, 2, 3, 4, 6 |
One of the five classical configurations described by Ptolemy (opposition, trine, square, sextile; the conjunction is treated as a bodily joining rather than a configuration). Ptolemy derives them from the musical ratios 1:2, 2:3, 3:4 and 5:6 of the circle (Tetrabiblos I.13).
Detection rule (all aspects): with Δ = |λ₁ − λ₂| mod 360 and d = min(Δ, 360 − Δ), an aspect of angle A (≤ 180°) is in orb when |d − A| ≤ orb. Applying vs. separating is decided by whether |d − A| is shrinking or growing as the faster body moves.
🔗 Related
- Family: 1 Major · index
- Siblings: Conjunction, Sextile, Square, Trine
- All aspects: Aspect Index · Aspects README
Traditional and modern attributions above are optional correspondences. Within Astrology Arith(m)etic the definition at the top of this note is the working law.
Sources (aspect arithmetic)
- Claudius Ptolemy, Tetrabiblos (2nd c. CE), Book I — trans. F. E. Robbins, Loeb Classical Library 435 (1940), public-domain text at LacusCurtius: https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Ptolemy/Tetrabiblos/home.html
- William Lilly, Christian Astrology (London, 1647), Book I (houses, orbs p. 107, essential dignities table p. 104) — public domain; orb table transcribed at https://www.renaissanceastrology.com/aspects.html and https://www.skyscript.co.uk/aspectorbs.html