Planet Longitudes in Babylonian Horoscopes

Astrological Origins by Cyril Fagan was published by his wife in 1971 after his death. In Chapter 14, “Six Babylonian Genitures,” Fagan set out to prove that the Babylonian zodiac was sidereal. Today we know that it’s unquestionably true that the Babylonians used a sidereal zodiac.

Fagan had to depend on tables for his computation but today we have computer programs that can instantly calculate charts for ancient dates.

A book published in 1998, almost 30 years after Fagan’s death, should interest every sidereal astrologer. Babylonian Horoscopes by Francesca Rochberg (Philadelphia: American Philosophical Society) has brought together all the known Babylonian horoscopes, 28 according to Rochberg. Several of these horoscopes have degree notations for the planets. Thus, we have definitive positions in the equal 30 degree Babylonian sidereal signs for the planets.

Rochberg used an average correction factor, employing a program designed by P. Huber, to adjust the longitudes, which gives approximate computed values. However with today’s astrological software we can get exact positions for any zodiac and compare them to the ancient texts. I have computed the horoscopes that have degrees listed, so anyone can see at a glance how the modern Fagan-Bradley and Lahiri/Krishnamurti longitudes compare to the degrees given in the Babylonian tablets. The actual tablets are illustrated in Rochberg’s book.

From the computed positions of the planets, we realize that the Babylonian scribes didn’t have the ability to be completely precise with planetary positions. Nevertheless, the majority of the positions are remarkably close to the Lahairi/Krishnamurti and Fagan-Bradley zodiacs of today. We need to admit to ourselves the origin of our precise modern zodiacs:

1. Fagan-Bradley: This ayanamsa is a construct based primarily on personal research by Cyril Fagan and Donald Bradley. Fagan based his ayanamsa on the historical research that was available in his time. He is credited with the discovery (from the astrological point of view) that the Babylonian zodiac was strictly sidereal. The Fagan-Bradley ayanamsa has been enthusiastically adopted by many western siderealists.

2. Lahiri: This ayanamsa is a contemporary one based on the research of the Indian government’s Calendar Reform Committee. The Committee Report was published in 1955. Lahiri’s ayanamsa comes the closest to a universally accepted value in India and among western Jyotish astrologers.

3. Krishnamurti: This is the personal ayanamsa of K.S. Krishnamurti which he claims to have discovered in very precise work with predictive timing techniques. This ayanamsa has become popular with modern Jyotish astrologers due primarily to dasa timing and placement of planets in divisional (varga) charts. Krishnamurti's books were published in the latter third of the 20th century. The difference between the Lahiri and Krishnamurti zodiacs is very small: 5 minutes 47 seconds.

There is no problem using any of these ayanamsas as long as their origins are understood, and no claims are made regarding their antiquity. As far as the the Babylonian horoscopes go, there is no evidence for a precise ayanamsa, although the scribes were amazingly accurate using methods crude by today's standards.

Babylonian Tablet Longitudes

The modern longitudes that come the closest to those on the ancient tablets are in red boldface. For interest, the Tropical longitudes have also been included. Calculations are by Solar Fire v 5.1.4.

Text 10: June 3, 235 BCE 4:00 a.m. LMT Babylon
Planet  Text Longitude Krishnamurti Fagan-Bradley Tropical at
Date of Birth
Venus 4 Taurus 28 Ari 47 27 Ari 48 21 Ari 29
Sun 12.5 Gemini 14 Gem 25 13 Gem 26 07 Gem 08
Saturn 6 Cancer 01 Can 33 00 Can 34 24 Gem 16
Mars 24 Cancer 26 Can 31 25 Can 32 19 Can 14

Text 16b: June 5, 200 BCE 5:00 a.m. LMT Babylon
Planet Text Longitude Krishnamurti Fagan-Bradley Tropical at
Date of Birth
Mars 10 Taurus 09 Tau 13 08 Tau 14 02 Tau 26
Venus 5 Gemini 03 Gem 22 02 Gem 23 26 Tau 34
Mercury 27 Gemini 25 Gem 17 24 Gem 18 18 Gem 29
Saturn 10 Virgo 08 Vir 17 07 Vir 18 01 Vir 29

Text 16a: October 31 199 BCE 5 a.m. LMT Babylon
Planet Text Longitude Krishnamurti Fagan-Bradley Tropical at
Date of Birth
Saturn 3 Libra 04 Lib 08 03 Lib 09 27 Vir 21
Mercury 8 Scorpio 18 Sco 43 17 Sco 44 11 Sco 56
Mars 10 Sagittarius 08 Sag 54 07 Sag 55 02 Sag 07
Venus 4 Capricorn 28 Sag 15 27 Sag 16 21 Sag 29
Jupiter 10 Capricorn 06 Cap 09 05 Cap 10 29 Sag 22

Text 23: January 5, 88 BCE 11:59 p.m. LMT Babylon
Planet Text Krishnamurti Fagan-Bradley
Mars 20 Leo 22 Leo 01 21 Leo 02
Mercury 26 Sagittarius 27 Sag 17 26 Sag 18
Venus 1 Pisces 01 Pis 41 00 Pis 42
Jupiter 27 Aries 26 Ari 45 25 Ari 46
Moon 5 Taurus 04 Tau 36 03 Tau 37
Saturn 20 Gemini 20 Gem 28 19 Gem 29

This horoscope (one of the more recent Babylonian charts) is interesting because it agrees with the longitudes in Babylonian star catalogues in that there is an average between the Lahiri/Krishnamurti and Fagan-Bradley degrees.

Text 27: April 16, 69 BCE 2:30 p.m. LMT Babylon
Planet Text Krishnamurti Fagan-Bradley Tropical at
Date of Brith
Mars 14 Libra 10 Lib 41 09 Lib 42 05 Lib 42
Jupiter 24 Sagittarius 22 Sag 47 21 Sag 48 17 Sag 48
Moon 18 Capricorn 29 Cap 20 28 Cap 21 24 Cap 21
Saturn 15 Aquarius 15 Aqu 15 14 Aqu 16 10 Aqu 15
Sun 30 Aries 28 Ari 27 27 Ari 28 23 Ari 28
Venus 13 Gemini 13 Gem 38 12 Gem 39 08 Gem 39

Calculating the above horoscope for the previous day to agree with the Moon
Planet Text Krishnamurti Fagan-Bradley
 Mars 14 Libra 11 Lib 01 R 10 Lib 02 R
Jupiter 24 Sagittarius 22 Sag 49 21 Sag 50
Moon 18 Capricorn 16 Cap 29 15 Cap 30
Saturn 15 Aquarius 15 Aqu 11 14 Aqu 12
Sun 30 Aries 27 Ari 30 26 Ari 31
Venus 13 Gemini 12 Gem 39 11 Gem 40

This horoscope is the most recent of the Babylonian genitures. Even the longitude of the Moon is given as computation apparently became more exact. Comparing these two dates highlights the problem with the Babylonian calculations. The Krishnamurti/Lahiri calculaitons fit better with the April 15 date, but the Sun is off by an extra degree. Scholars had to find these dates by trial and error. As astrologers we can be grateful for their work. All we have to do is plug the data into our astrological programs!

Posted by Therese Hamilton
April 2, 2005

© 2005 Therese Hamilton, East-West Publishing
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