by James A. Eshelman

(The following is reproduced here (with editing), by permission of the author and the publisher, from Black Pearl Vol. II, No. 1. Copyright College of Thelema, All rights reserved.)

Defining the Northern hemisphere’s vernal equinoctial point as 0° Aries, the zodiac, as known to most casual students of astrology — and, for that matter, most professionals — is called the Tropical zodiac. Throughout my various writings, frequent reference is made to a less familiar framework titled the Sidereal zodiac. All that most people know about the Sidereal zodiac is that sign placements usually shift one sign backwards!

Yet, despite this relative obscurity, the Sidereal zodiac, and the associated approach to astrology put forth by Cyril Fagan and his coworkers, has revolutionized astrological research and practice over the last 50 to 60 years. Even allowing every honest skeptical concession to its opponents, I cannot honestly admit any facts contrary to these:

  1. The Tropical zodiac is a fiction. It simply doesn’t exist, except in the minds of its proponents.
  2. The Sidereal zodiac — the same zodiac that was used from astrology’s dawn — exists objectively, has demonstrable empirical and statistical validity, and is the only legitimate zodiac existing in Nature.

These are strong statements, I know. This article, with others planned to elaborate its main points, will back them up.

One can always take a gracious and tolerant high road, of course, and not insist too loudly on either of these points. Such gracious tolerance takes the form of minding one’s own business and, if pressed on the issue, saying that someone may, of course, use whatever approach they wish. One also must have compassion for those who have invested many decades in a different way of knowing about things, and have decided that it’s too late to start all over again. I support and practice all of these behaviors in my social interaction with other astrologers. But — as we move forward into the present series of articles — I am less likely to practice them here. I ask my readers to consider that graciousness is a social emollient, and tolerance is a respect and acceptance of others’ beliefs and life choices. Neither has much to do with science — with the facts. Those noble virtues, graciousness and tolerance, are enemies of truth.

Perhaps I merely repeat the error that Frater C.R.C. made in Spain, “showing unto them the errors of our arts, and how they might be corrected, and from whence they should gather the true indicia of the times to come, and wherein they ought to agree with those things that are past.” I may well find that, despite the passage of six centuries, “it is to them a laughing matter; and being a new thing unto them, they fear that their great name would be lessened if they should now again begin to learn, and acknowledge their many years’ errors, to which they were accustomed, and wherewith they had gained them enough.” I can only respond, as did his true brethren: “Whoso loves unquietness, let him be reformed.”

Here follows an overview of what the Sidereal zodiac is, its modern history, and some of the main categories of the arguments for its authenticity. Several sections below will require more articles to substantiate the flat claims made here. Subsequent installments of this series will undertake that very task of elaborating these preliminary points. Most of the information, by the way, has been available in the public record for decades.


The Sidereal zodiac, like the more familiar Tropical zodiac (currently used by most Western astrologers), is divided into 12 equal segments of 30° each. These divisions bear the familiar names Aries, Taurus, etc. The basic difference is that the start of the Tropical zodiac (0° Aries) is permanently identified with the Vernal Equinox, while the Sidereal zodiac is measured in a way that fixes it against the starry celestial backdrop. The boundaries of the Sidereal zodiac have been precisely determined by purely observational means, confirmed by independent archaeological investigation. Because the Vernal Equinox is not fixed against the same celestial backdrop, the Tropical zodiac is in constant backwards motion in relation to the Sidereal zodiac (the “precession of the equinoxes”). As a result, “signs” of the same name in these zodiacs do not presently occupy the same areas of space.


In 1944, Cyril Fagan discovered the superiority of Sidereal Solar and Lunar Returns (“Solunars”) over their Tropical counterparts. These returns, calculated in a precession-free reference frame, yield quite different results from Tropical returns. For example, the difference in the time of a Solar Return amounts to a whole day at age 72.

The literature on this subject is very rich, though much is out of print. You may be able to find two books on the subject: Solar & Lunar Returns by Donald A. Bradley (1948) and Interpreting Solar Returns by James A. Eshelman (1979).


Fagan began favoring the use of a sidereal, or non-precessing, zodiac such as Eastern astrologers have used for centuries. He felt it made more sense than continuing to use a precessing (Tropical) zodiac but deleting precession for prediction purposes. Sidereal sign-placements also began to provide solutions for many confusing problems of astrological symbolism. In this early, formative stage of Western Sidereal astrology, Fagan adopted the leading Hindu stellar zodiac, which fixes the star Spica at 0°00'00" Libra for all time. This zodiac differed from the contemporary Tropical zodiac by about 23° in the mid-1940s.


Donald Bradley entered the scene in the late 1940s. Then an established advocate of the Tropical zodiac, Bradley undertook what was at that time the largest, most carefully performed statistical examination of astrology’s fundamental precepts. Published in 1950 as Profession & Birth Date, Bradley’s study of 2,492 eminent clergymen surprised him by indicating that, while twelve equal divisions of the zodiac do exist, their boundaries are not where Tropical tradition places them. In fact, Bradley’s work suggested that, in the 1940s, a new sign began about where Tropicalists mark 24° of each sign, not at 0°.

Bradley continued this avenue of research over the remaining quarter century of his life. He published a consolidation of the cumulative results shortly before his death. The statistical concepts and fascinating factual implications cannot be summarized in a few sentences, but can be easily explained even to lay readers if one has a bit of patience. Because they lead to explorations not only of statistics, but also of zodiacal symbolism, mythology, and practical interpretation, these investigations are among of the most interesting and valuable areas of this study, and are high on our priority list for elaborating in future installments.


Bradley’s statistical determination (that a new sign begins about where Tropicalists mark 24° of each sign) differed by 1° from Fagan’s initial speculation. Bradley noted that this purely empirical determination (which has since been replicated with other large data samples) carried further symbolic virtues. For instance, it placed the star Aldebaran, “the Bull’s Eye,” exactly at 15° Taurus, the “bull’s-eye” of this original first sign of the zodiac. Spica, symbolically the sheaf of wheat in Virgo’s hands, was now found at 29° Virgo, not 0° Libra. Shortly thereafter, Fagan verified these speculations when he solved the mystery of the origin of traditional exaltation degrees (hypsomata — see Zodiacs Old & New), thereby determining to the nearest degree the boundaries of the ancient Egypto-Babylonian zodiac. Spica was officially shifted, by Fagan, Bradley, and others who had by that time joined them, to 29°00'00" Virgo.

Yet, no single “fixed” star can reasonably be presumed to determine the structure of the entire zodiac. These Sidereal longitudes of Spica, Aldebaran, etc. were known to be near-approximations at best, and not precise “permanent residences” by which a zodiac is defined. Current Sidereal theorists generally presume that their zodiac is the resultant of the harmonic interplay of all galactic and extra-galactic material, visible and invisible. In other words, it is a “field” in which the relative positions of the planets produce astrological effects, a concept by no means out of alignment with either progressive physics or Thelemic cosmology.


In 1956, a dozen years after Fagan’s initial discovery, Bradley began investigating Sidereal Solar and Lunar Cardinal Ingresses; that is, charts for the moments that the Sun or Moon entered one of the Sidereal Cardinal signs. The accuracy of his calculations was naturally dependent on the exact locations of Sidereal 0° Aries, Cancer, Libra, and Capricorn. A half-degree error in these points would displace the timing of a Lunar Ingress by about an hour, or of a Solar Ingress by about 12 hours. Initially, the Solar Ingress results were quite disappointing. Sidereal Lunar Ingresses, however, were exceptionally illuminating. Bradley found that by adjusting the zero-point by only 0°06', these Lunar Ingresses were often nearly perfect in their symbolic representations of socio-political events and natural phenomena. Spica was temporarily redefined as marking 29°06' Virgo.

These six minutes altered by about 2½ hours the timing of Solar Ingresses, miraculously transforming them, like the Lunar Ingresses, into valid mundane charts. A further adjustment of only 0°00'05" produced the most significant “polishing” improvement on this already pleasing technique. Spica, therefore, was redefined as marking 29°06'05" Virgo for the epoch 1950.0, placing the mean longitude of the Vernal Point at 5°57'28".64 Pisces for the same point in time. This defines what was named the Synetic Vernal Point (S.V.P.), utilized by Western Siderealists since 1957. It is presumed to be in error by no more than a few seconds (if that much). Thus, no longer are the boundaries of the twelve zodiacal divisions even nominally dependent on any single star with its own proper motion, but rather on a truly sidereal matrix that encompasses the totality of space.


Two important corroborations deserve mention in closing this overview. One, statistical in nature, arose from a discovery made by Bradley after his initial experiments with Sidereal ingresses. Investigating Sidereal Lunar Capricorn Ingresses (“Caplunars”) for record rainfalls, he found that Jupiter appeared near the angles of these charts at the localities of the cloud-bursters many times more than normal expectation would allow. Further pursuit of this led to a grant from the National Science Foundation administered by New York University to continue this research and related studies. This “Jupiter effect,” awesomely replicated in Bradley’s larger-scale studies, naturally depends upon the correct placement of the Sidereal zodiacal boundaries, and lends considerable support to their defined locations.


The second corroboration, from archaeological sources and non-astrological scholars who study the history of astrology and astronomy, was unknown to either Fagan or Bradley during their lives. In 1958 (a year after Bradley’s published determination of the S.V.P.), Peter Huber published some noteworthy findings on the Babylonian zodiac. In order to determine the boundaries of the zodiac the ancient Babylonians used, Huber compared the calculated dates of planetary conjunctions with certain stars, as recorded in Babylonian astronomical texts. Huber’s conclusions, published in the German journal Centaurus (1958, Vol. IX, pp. 192-208), were that the Babylonian zodiac, adjusted to the epoch —100 (101 BCE), placed the Vernal Point at 4°28' Aries plus-minus 20'. The Fagan-Bradley S.V.P., for the same epoch, locates the Vernal Point at 4°27' Aries, agreeing within 0°01’ of arc!

This page last updated 25 Nov 2008 E.V.