# Sesquiquadrate: the 135° minor aspect in a birth chart > What a sesquiquadrate is in astrology: the 135° angle, a square plus a semi-square, a 1-2° orb, the eighth harmonic, and how to read it in a real chart. URL: https://kb.astroway.info/en/aspects/sesquiquadrate A sesquiquadrate is an aspect between two planets that stand 135° apart along the ecliptic. The name comes from the Latin sesqui, one and a half: the angle is a square and a half, 90° plus 45°. English texts also call it a sesquisquare or a trioctile, three eighths of the circle. The sesquiquadrate is a minor aspect and, together with the [semi-square](/en/aspects/semisquare), forms the family of aspects in multiples of 45°. ## Geometry: three eighths of the circle Dividing the circle into eight parts gives the angles 45°, 90°, 135° and 180°. The square and opposition in this series are major aspects; the semi-square and sesquiquadrate are minor. Astrologers who work with harmonics place all four, together with the conjunction, in the eighth harmonic: angles of tension that demand action. The sesquiquadrate is easy to find once you remember that it completes the semi-square to an opposition: 45° + 135° = 180°. If two planets are in opposition, any third planet in semi-square to one of them will be in sesquiquadrate to the other. An angle of 135° equals four and a half signs, so the sesquiquadrate is not tied to a pair of signs. A planet at 0° Aries is in sesquiquadrate to one at 15° Leo, and a planet at 20° Aries to one at 5° Virgo. The signs can belong to any element or modality, and the aspect itself tells you nothing about them. ## Where the aspect comes from The sesquiquadrate is one of the angles Johannes Kepler proposed in the early 17th century while looking for a geometric basis for astrology akin to musical intervals. Before him, aspects were counted by sign, and the traditional system had no angle that splits a sign in half. In the 20th century, multiples of 45° became the backbone of Alfred Witte's Hamburg School and of Reinhold Ebertin's cosmobiology. On their 90° dial the semi-square and the sesquiquadrate fall on the same point, so for these schools they are essentially one aspect. Ordinary natal practice keeps them apart and usually treats the sesquiquadrate as slightly stronger than the semi-square, because it lies closer to the opposition. ## The orb of a sesquiquadrate The sesquiquadrate gets a narrow [orb](/en/aspects/orbs) like other minor aspects: 1-2°, up to 2-3° with the Sun or Moon. Schools that use the 90° dial allow even less. Most astrologers ignore one wider than 2° and consider one within 1° noticeable, especially when a luminary is involved. ## How to read a sesquiquadrate In character the sesquiquadrate is close to the square: two functions pull in different directions, and the person feels it as inner pressure. The difference lies in scale and visibility. A square usually describes a conflict the person knows well; a sesquiquadrate describes tension that shows up in episodes, when in certain situations two parts of the character suddenly stop cooperating. Modern writers often describe it as an aspect that throws a person off balance and forces a rethink of habitual ways of acting. The order of reading is the usual one: - **Planets.** Which functions are under tension. A sesquiquadrate of the Sun to the Moon speaks of will and needs; one of Jupiter to Uranus, of expansion and sudden change. - **Signs.** How each planet acts. The signs are arbitrary, so read each planet in its own sign. - **Exactness and role.** A sesquiquadrate within 1° that involves a luminary or the ruler of the Ascendant deserves attention. The sesquiquadrate refines the picture drawn by the major aspects. It can explain why two planets without a major link still clearly affect each other. ## Example: the sesquiquadrate in Emmanuel Macron's chart In [Emmanuel Macron's chart](/en/people/emmanuel-macron) the Sun is at 29°25′ Sagittarius and the Moon at 14°28′ Taurus. The angle between them is about 135°03′, an orb of 0°03′. This is an almost exact sesquiquadrate between the luminaries, and it can be stated only because the birth time is known: the Moon moves 1° in about two hours, and without a time such an aspect cannot be established. Tradition would read tension between the Sun and Moon as a gap between what a person strives for and what they need for inner calm. In a sesquiquadrate that gap is not constant but situational: it surfaces when circumstances force a choice between a goal and comfort. This describes a link between two functions of the chart, not a judgement of the person. ## How to find a sesquiquadrate in your own chart Most software omits the sesquiquadrate from its aspect tables, so you find it yourself. Convert the planets' positions to absolute degrees: Aries 0-30°, Taurus 30-60°, Gemini 60-90° and so on to Pisces at 330-360°. Macron's Sun at 29°25′ Sagittarius becomes 269°25′, his Moon at 14°28′ Taurus becomes 44°28′. Subtract the smaller number from the larger: here that gives 224°57′. If the result is over 180°, subtract it from 360°, which gives 135°03′. An angle within 1-2° of 135° is a sesquiquadrate. A useful hint: as with the semi-square, the two planets' degrees within their signs differ by 15°. To find a possible partner, add 135° to a planet's position and subtract 135°: for a planet at 0° Aries that gives 15° Leo and 15° Scorpio. ## Sesquiquadrates in configurations The best-known figure with sesquiquadrates goes by the names Thor's hammer and fist of God: two planets in square and a third in sesquiquadrate to both. The apex stands roughly opposite the midpoint of the square and is read as the point where the square's tension finds its outlet. The section has no separate page for this figure yet. The classic configurations of major aspects, including the [T-square](/en/aspects/patterns/t-square), are covered under [aspect patterns](/en/aspects/patterns).