I-19 Powell’s hermetic astrological charts and tabulations

Hermetic Astrology I (HA1), Chap. 3

The length of time required for the Sun to travel its complete cycle through the 12 constellations of the Zodiac is 25,920 years (an astronomical fact). The average length of time allocable to each constellation is thus 25,920/12, or 2160 years.

In Sidereal Zodiac (SZ), Robert Powell updates “the original definition of the zodiac by Babylonian astronomers” to our own time by formally defining it “for the epoch 1950.0, in line with conventional astronomical practice” (p. 12). That practice, however, appears to involve some other changes from Babylonian practice, changes made by the Greek Hipparchus by the second century B.C. One of these is the use of the “ecliptic” rather than the “zodiacal belt” as a frame of reference. In SZ, p. 1, Powell states:

In modern astronomy the zodiacal belt is defined in relation to the path of the Sun through the fixed stars, which path is taken as the middle of the belt, so that the zodiacal belt, usually taken to be 16 degrees wide, by this definition extends 8 degrees north and 8 degrees south of the path of the Sun. The zodiacal belt is thus a belt of fixed stars along the middle of which runs the path of the Sun and contains also the paths of the Moon and the five planets known to the ancients through naked eye observation—Mercury, Venus, Mars, Jupiter, and Saturn.

Another is given by Powell as follows (SZ, pp. 9-10):

The vernal point, i.e., the location of the Sun in the ecliptic at the time of vernal equinox, was adopted in Greek astronomy as the beginning of the ecliptic, apparently because the vernal equinox was considered by Greek astronomers as the start of the year. This represents another point of difference between Greek and Babylonian astronomy. Since the Babylonian year consisted of twelve or thirteen lunar months, the start of the year was related to a lunar phenomenon, namely the appearance of the first new Moon of the year, which was, generally speaking (at least in later Babylonian times), the new Moon falling nearest to the vernal equinox. However, as early as the fifth century B.C., the Greek astronomer Euctemon defined a seasonal calendar, consisting of twelve (approximately) equal solar months, related to the solar phenomena of equinoxes and solstices. The months in Euctemon’s calendar have the same names— the equivalent Greek names—as the signs of the zodiac in Babylonian astronomy. Thus the solar month commencing on the day of the vernal equinox was called by Euctemon the month of Aries. Similarly, the solar month commencing on the day of the summer solstice was called the month of Cancer.... This calendrical system is still in vogue today in astrology.

Christians will readily recognize the lunar nature of the Yahweh faith, since the Passover, and the Christian Easter celebration, are both related to the vernal equinox in terms of its proximity to the new Moon. At the time these systems were established, it was Aries that was arising at sunrise on the eastern horizon at the vernal equinox, but today this is no longer true due to the precession of the equinoxes (an astronomical fact that conventional astrology ignores). See 4 Brit 534, “equinox” and “equinoxes, precession of the,” and 1 Brit 551, “Aries.”

Because humanity must come to recognize the “ages” preordained by its relationship to the heavenly bodies (as the outward manifestation of spiritual beings and their forces), it is important to understand that it is the “vernal point” that determines the dates of the “ages.” It is based upon the zodiacal sign rising in the eastern sky at sunrise at the vernal (spring) equinox. Due to the “precession of the equinoxes,” this point retrogresses one degree each 72 years so that an “age” consists of 2,160 years and a “zodiacal year” of twelve ages consists of 25,920 years.

In order to relate to the reality of the changing relationship of the heavenly bodies to the Earth by taking the precession of the equinoxes into account, Powell defines the “sidereal zodiac” by fixing it in relation to the brightest star in the zodiacal belt, Aldebaran, located approximately in the middle of the constellation Taurus (as the eye of the bull), placing the zero point exactly 45 degrees west of Aldebaran on that date, i.e., 1950 (pp. 27 and 32). His portrayal of the sidereal zodiac, so defined, is shown below. ^{(click here to view zodiac)}