# Opposition aspect: the 180° angle in a birth chart > What an opposition means in astrology: the 180° angle, opposite signs and house axes, projection, out-of-sign oppositions, the Full Moon, and a real chart example. URL: https://kb.astroway.info/en/aspects/opposition An opposition is an aspect between two points of a chart that stand 180° apart, at opposite ends of the circle. It is one of the five major aspects and, together with the square, counts as a hard aspect. The tension here has a different geometry. In a square the planets press on each other from the side; in an opposition they look each other straight in the face. That is why an opposition is read as a polarity the person learns to hold in balance. ## Geometry: why 180° The opposition cuts the circle in half. Each planet has the other directly across from it, with five signs between them on either side. The classic pairs of opposite signs are Aries and Libra, Taurus and Scorpio, Gemini and Sagittarius, Cancer and Capricorn, Leo and Aquarius, Virgo and Pisces. These pairs share two features. First, both signs belong to the same modality: Aries and Libra are cardinal, Taurus and Scorpio fixed, Gemini and Sagittarius mutable. Second, they share a polarity. Fire always faces air and earth always faces water, and these elements are traditionally considered compatible: fire needs air, earth needs water. This is the main difference between an opposition and a square. In a square the signs share a modality but their elements do not mix, so the conflict is harsher. In an opposition the signs speak related languages from opposite positions. Each has what the other lacks, which is why the opposition is often described as two halves of one whole. ## The orb of an opposition Oppositions usually get the same wide orb as conjunctions: about 7-8° between personal planets and 8-10° with the Sun or Moon. The more exact the angle, the more noticeable the polarity. How to set orbs for different pairs of planets, and why schools disagree, is covered in [aspect orbs](/en/aspects/orbs). Like any aspect, an opposition is applying while the faster planet is still approaching the exact angle and separating once it has passed it. The opposition is the farthest point in the cycle of two planets: after it, the faster planet begins to close in on the slower one again. ## House axes An opposition often falls across opposite houses, and then it links two areas of life that astrology has always considered in pairs. These pairs are called axes. - **1st-7th.** Self and other: personal initiative against partnership, open relationships and rivals. - **2nd-8th.** Mine and shared: one's own money and values against other people's resources, debts and inheritance. - **3rd-9th.** Near and far: everyday communication and learning against worldview, long journeys and higher education. - **4th-10th.** Home and world: family and roots against career, status and public role. - **5th-11th.** Personal and collective: one's own creativity and pleasure against friends, groups and shared plans. - **6th-12th.** Visible and hidden: daily work and routine against retreat and whatever happens behind the scenes. When planets sit at the two ends of one axis, the person feels the two areas pulling in different directions. The answer is rarely to pick one. More often it is a matter of rhythm: a period when one side matters most gives way to a period when the other does. ## Projection: when one end lives in other people The most characteristic feature of an opposition is that the person often fails to recognise one of its halves as their own. They meet it in other people instead: a partner, a boss, an opponent. Modern psychological astrology calls this projection. The mechanism is simple. It is easier to identify with one pole, the more familiar one or the one closer to how the person sees themselves. The other planet then seems to move out into the surroundings. Someone with Venus opposite Mars may think of themselves as gentle and keep running into abrasive people, although the abrasiveness belongs to them as well. Relationships are therefore where an opposition most often shows itself. What irritates or attracts us in others frequently points to where the other end of the axis lies. ## Out-of-sign oppositions Some oppositions have an angle close to 180° while the signs are not opposite. A planet at 29° Aries and another at 1° Scorpio are 182° apart, an opposition by orb. Aries and Scorpio, however, are not a pair of opposite signs: Aries is cardinal fire, Scorpio fixed water. This is called an out-of-sign or dissociate opposition. Most astrologers count it but read it without the kinship of a regular opposition: the confrontation remains, while the complementary elements and the shared modality are missing. Chart software lists it as an ordinary opposition. ## The Full Moon as an opposition The best-known opposition in astrology needs no chart at all: it is the Full Moon. When the Moon stands exactly opposite the Sun it is fully lit, and that moment is what we call the Full Moon. Every Full Moon is an opposition of the Sun and Moon, and every Sun-Moon opposition is a Full Moon. Astrologers who work with lunar phases describe people born near the Full Moon through that same polarity. The Sun stands for conscious will and who the person believes they are; the Moon for needs, habits and emotional reactions. In opposition the two sides are as far apart as they can be and, at the same time, in full view of each other. Hence the traditional reading: awareness of the opposites within oneself, swinging between them, and a strong orientation toward other people. A Full Moon always falls in opposite signs of the same polarity, so the Sun and Moon in such a chart sit in a compatible pair of elements: fire with air, or earth with water. ## Example: oppositions in Donald Trump's chart [Donald Trump's chart](/en/people/donald-trump) has two oppositions, and both run through the Moon. The first links the two lights. The Sun is at 22°55′ Gemini, the Moon at 21°12′ Sagittarius, an orb of 1°43′. Gemini and Sagittarius form the mutable axis, air facing fire. This is an opposition in the full sense: opposite signs, one modality, compatible elements. He was born on the day of a Full Moon. By the positions in the chart the Moon had not yet reached the exact angle and was still catching up with the opposition, so in terms of motion the aspect was applying. The Sun also stands in the 10th house and the Moon in the 4th, which puts the opposition on the 4th-10th axis: home against public role. The second opposition links the Moon with Uranus at 17°53′ Gemini, an orb of 3°18′, separating. Uranus is in the 10th house as well, so this is the same axis. Tradition reads a Moon-Uranus contact as a need for independence and change, quick emotional reactions, and impatience with routine. Through the opposition the theme often arrives by way of other people: the surprises come from outside. The remaining tension in the chart comes from Mercury square Neptune, the only [square](/en/aspects/square) within AstroWay's orbs. ## Oppositions in configurations The opposition is the backbone of several figures. When a third planet squares both of its ends, the result is a [T-square](/en/aspects/patterns/t-square), the most common hard configuration. Two oppositions joined by four squares form a grand cross. The opposition's counterpart is the [conjunction](/en/aspects/conjunction): there the planets stand together, here they stand across from each other, and between them the two aspects open and close the cycle of any pair of planets.