Precessional & Galactic Astrology

On the Tertiary and Quaternary Motions.

Temporal cycles are fundamental to the art of astrology. For, what is the art (particularly in its predictive context) if not the interpretive consideration of stellar and planetary cycles? Seconds, minutes, hours, months, years and the epicycles of the planets in their respective orbits against the canopy of the fixed stars and zodiac, together form a vast schema – a celestial drama, a cosmic mystery – whose inherent meaning and purpose is made fathomable only to the astrologer. This is the Great Celestial Book which has been read by astrologers alone since the development of omenic astrology in Mesopotamia nearly four-thousand years ago. But there could be no astrology in the absence of the recurring cycles precipitated by the various rotations and revolutions of celestial bodies. In this blog post, we will investigate two such long-term cosmic cycles, less commonly considered by astrologers – the precessional and the galactic – and how these respectively correspond to the tertiary and quaternary motions of the heavens.

Before we begin, however, we must first address the two cyclical motions with which astrologers are more commonly concerned: primary and secondary motion.

Primary motion is the apparent clockwise movement of the zodiac, fixed stars and planets from east to west and is caused by the diurnal rotation of the Earth upon its axis. Astrologically, primary motion makes possible the fundamental notions of an Ascendant, houses (including their angularity, succedency and cadency) and planets placed on the angles (the ASC/DSC and MC/IC axes), such as the culmination of a planet at the local meridian (Midheaven). Primary motion corresponds to the Egyptian contribution to the art, which was largely diurnal in nature, and was brought about by the temple astronomer-priest’s practice of observing certain stars and decanal asterisms as they rose on the eastern horizon. Hence, the concept of the horoskopos, or “hour watcher,” which gave way to the Ascendant in horoscopic astrology.

Secondary motion is the apparent counterclockwise movement of direct motion planets from west to east and is caused by the annual revolution of the Earth and other planets around the Sun. Astrologically, secondary motion is responsible for the Sun’s apparent transit through the signs. The other planets’ zodiacal positions are also influenced by secondary motion (in addition to their own orbits), as are the terrestrial seasons. Secondary motion corresponds to the Babylonian contribution to the art was based on their division of the ecliptic into twelve equal 30° arc segments, associated with the zodiacal constellations, through which the Sun and other planets passed over the course of one annual solar circuit. The observation of the planets in signs informed their mundane judgements in the context of omenic astrology, which was largely mundane and/or political in nature.

Again, primary and secondary motion are major components of the celestial mechanics underlying astrological theory, but there are two longer term cycles that are rarely considered in astrological delineation; we will call these are tertiary and quaternary motion.

Tertiary motion is the nearly imperceptible clockwise movement of the vernal equinoctial point along the ecliptic and is caused by the slow precessional gyration of the Earth upon its axis. The equinoctial point retrogrades at a rate of about one degree every 72 years; this means it will go through the thirty degrees of a sign over the course of approximately 2,160 years, completing a Great Year after about 25,920 tropical years, after passing through all 12 signs. Each of the Great Months (the 2,160 year period, or age, during which each sign hosts the equinoctial point) is characterized by the symbolic nature of a particular sign. For instance, during the Taurian Age (approximately 4000-2000 BCE), bovine symbolism permeated religious and cultural expression; e.g., Gugulanna, the “Bull of Heaven”, in Mesopotamia; Bat, Apis & Hathor in Egypt; the Gavaevodata of the Zoroastrians; Io and the Minotaur of the Minoans; etc. Symbolically, homage was paid to the zodiacal host of the vernal equinox, which may be seen as the annual Ascendant; because, just as the diurnal Ascendant of the natal chart signifies the persona or outward expression and physique of the native, so too does the equinox signify the mundane energetic expression, hence the use of Aries ingress charts in mundane judgement.

In the tropical system, the vernal equinox occurs in Aries. This designation fixes the equinoctial point at what is known as the First Point of Aries and aligns the four seasons to the cardinal signs on the angles at the ASC/DSC and MC/IC axes. However, due to axial precession, this point has preceded to around 6° Pisces (0-hour RA, or right ascension, per “equinox 2000.0”). Based on boundaries defined by the International Astronomical Union (IAU), the equinoctial point ingressed the sign of Pisces in 68 BCE and will ingress Aquarius in 2597 CE. This means that, sidereally, we are in the early degrees of the Piscean Age, which should be obvious considering the abundance of Piscean symbolism over the last 2,000 years, largely centered around Christianity (e.g., the acrostic ΙΧΘΥΣ, Greek Icthys or “fish”; the two fishes of the “feeding of the 5,000”; Jesus as the “fisher of men”; etc.).

Quaternary motion is the movement of the galactic center, or GC, through the signs of the zodiac and is caused by the revolution of our solar system around the center of the Milky Way galaxy. It takes approximately 238 million years for the GC to move through all twelve signs, spending approximately 20 million years in each (approx. 667,000 years in each degree). Currently, the degree of the galactic center is 27° Sagittarius. While we should certainly consider the general Sagittarian and Jupiterian (the sign ruler) significations in delineation, this immense amount of time may be made more manageable by also considering the significations of smaller segments of the sign, such as the decan ruler (Saturn), the bound ruler (also Saturn) and the planet ruling the individual monomoiriac degree (the Moon, according to Paulus Alexandrinus’ attributions), as these will allow for finer detail in tighter temporal ranges.

In the context of chart delineation, the broader precessional (tertiary motion) and galactic (quaternary motion) themes may be considered as contributing a sort of baseline hum or drone upon which the tighter zodiacal (annual; secondary motion) and planetary (diurnal; primary motion) elements rest. Four-part harmony in musical composition is an apt analogy for this concept. Imagine that the planets in signs and houses are the soprano and alto lines in the treble clef; together, they form the melody and its counterpoint. The basis supporting these two melodic figures are the tenor and bass lines in the bass clef, as they provide intermediate tonal coloration and set the root harmonic foundation, respectively. Think of the precessional and galactic significations as providing a similar tonal foundation supporting the planetary melody and zodiacal counterpoint in any given chart.