Sun/Moon Midpoint

Definition

The Sun/Moon midpoint is the half-sum of the Sun's and Moon's longitudes — the zodiac point exactly between the two lights on their shorter arc, with an inverse half-sum 180° opposite. Cosmobiology and Uranian astrology treat it as the single most important midpoint in the chart, because it merges the symbolism of the day light and the night light and is held to register how conscious will (the Sun) and emotional, habitual nature (the Moon) come together in a person.

In Tradition

In the Cosmobiology and Uranian schools, a planet making a hard aspect to the Sun/Moon midpoint — conjunction, opposition, square, semi-square, sesquisquare — is read as active in how the chart integrates self and feeling, with the contacting planet adding its own colour. The midpoint carries particular weight in synastry, the comparison of two people's charts: a contact from one chart's planets to the other chart's Sun/Moon midpoint is read as deeply formative for the relationship.

In Practice

Astrologers find the Sun/Moon midpoint by averaging the two longitudes, reducing modulo 360° if needed, and then check the birth chart and any timing series for hard-aspect contacts to that point and to its 180° inverse, with tight orbs of 1° to 1.5°. Ebertin's framework supplies a ready-made combined-meaning gloss for each contacting planet — Saturn at the Sun/Moon midpoint as restriction or maturing of the integration, Venus as ease or affection in it. On the 90° dial, the natal Sun/Moon midpoint and its multiples of 90° all collapse onto one dial position, making the contacts easy to inspect.

Historical Origin

The doctrine is established in Alfred Witte's Hamburg School (early twentieth century) and given canonical form in Reinhold Ebertin's Kombination der Gestirneinflüsse (1940; English The Combination of Stellar Influences, AFA 1972, trans. Brummund). Modern treatments by Hand (Horoscope Symbols) and Tyl (Synthesis & Counseling) keep the technique within mainstream Western practice.

Further Reading

  • Reinhold Ebertin, The Combination of Stellar Influences
  • Robert Hand, Horoscope Symbols
  • Noel Tyl, Synthesis & Counseling in Astrology