The Cochrane Ayanamsha

Copyright © 2018 All Rights Reserved

by David Cochrane


The Cochrane ayanamsha has a value of 355 degrees 27 min 34 sec on January 1, 1900. This is very different from most ayanamshas. For example, the Fagan/Bradley ayanamsha on this date is 23 deg 20 min 55 sec and the Lahiri ayanamsha is 22 deg 27 min 55 sec. The difference between the Fagan/Bradley and the Lahiri ayanamsha is less than a degree, while both of them are over 27 degrees different from the Cochrane ayanamsha.

To convert tropical positions to sidereal positions for someone born within about the past 100 years you subtract about 22 to 25 degrees depending on the data and the ayanamsha used. A few ayanamshas are slightly outside this range, but the Cochrane ayanamsha is very different. Instead of subtracting 22 to 25 degrees, you add 3 to 5 degrees.

Another difference between the Cochrane ayanamsha and other ayanamshas is that with the Cochrane ayanamsha the tropical zodiac is considered the primary zodiac and of particular interest is where the sidereal Zero-Aries point is in the tropical zodiac rather than where the tropical Zero-Aries point is in the sidereal zodiac. According to most theories of the Great Ages we are currently in the Piscean Age because tropical Zero-Aries is in the sidereal sign of Pisces. However, the Cochrane ayanamsha is designed, as described below, with a frame of reference in which the tropical zodiac is the primary zodiac and from this perspective what is important is that currently sidereal Zero-Aries is in the tropical sign of Pisces so using the Cochrane ayanamsha and this point of view, there is agreement that we are currently in the Piscean Age. Note, however, the sidereal signs move forward through the tropical zodiac, and tropical signs therefore move retrograde through the sidereal signs, so from the more common point of view tropical Zero-Aries is moving in a retrograde motion through the sidereal sign of Pisces and when it reaches the sign of Aquarius the Aquarian Age will begin. However, using the point of view used with the Cochrane ayanamsha sidereal Zero-Aries is moving in direct motion through tropical Pisces and the next Age will be the Age of Aries, not the Age of Aquarius. According to the Cochrane ayanamsha the age of Aries begins in the year 2225 and the tropical and sidereal signs will be identical in the year 2225, whereas according to most ayanamshas the tropical zodiac and the sidereal zodiac were identical approximately 2,000 years ago.


The Cochrane ayanamsha is based on a theoretical framework for astrology in which sacred geometry is the foundation of astrology. This theory is explained in detail in several tutorial youtube videos, one of which is the video "How Astrology Works: A New Theoretical Framework" at Key concepts presented in this video are summarized below.

Some key concepts for understanding why there is a tropical zodiac are: (1) According to some recently develop ideas in physics there are jewel-like structures in a higher dimensional space. It is proposed that the zodiac is one of these jewel-like structures, (2) Spin is a fundmental principle of the Universe and the Spin of the Earth on its axis and the revolution of the Earth around the Sun generate a zodiac through a process of growth sequences of numbers known as pisano periods and prime numbers and a process of dimension reduction. This process is explained in some detail in the video referenced above. (3) The intersection of the Great Circles of the ecliptic plane and the equatorial plane create the Zero-Aries and Zero-Libra points of the tropical zodiac.


The Galactic Center is, in a sense, the Sun of the Sun. In other words the Sun travels around the Sun just as the Earth and other planets travel around the Sun. In antropomorphic terms the Sun is analogous to a father and the Galactic Center is analogous to a grandfather. A zodiac is formed by the relationship of the Earth to Galactic Sun in a very similar way to how a zodiac is created by the relationship of the Earth to the Sun.

When the Earth is inclined with a maximum tilt away from the Sun in the Earth's annual revolution around the Sun of approximately 365.25 days the Sun is exactly at 0 Capricorn. Similarly, when the Earth is at maximum tilt away from the Galactic center in the cycle of approximately 25,800 years the Galactic Center is exactly at 0 Capricorn in a galactic scale zodiac rather than the solar system scale zodiac. The zodiac at the scale of the solar system, or in other words the zodiac created by the Earth's relationship to the Sun, is called the tropical zodiac. The zodiac at the scale of the galaxy, or in other words the zodiac that is created by relationship of the Earth to the Galactic Center, is called the sidereal zodiac. In the year 2225 the Galactic Center will reach exactly 0 Capricorn in the tropical zodiac and at this time the tropical and sidereal zodiacs are identical.

Just as 1/12 of approximately 365.25 days is the duration that the Sun is in each tropical zodiac sign, the Galactic center is in a sign for approximately 1/12 of 25,800 years, which is approximately 2,156 years.


The sidereal zodiac is a zodiac that is based on a relationship the Galactic Center to the Zero-Aries and Zero-Capricorn points in the tropical zodiac. The sidereal zodiac is actually not based on the fixed stars as has been largely assumed but rather it is based on the geometry of the heavens, just as the tropical zodiac is also based on this sacred geometry. The sidereal zodiac is another layer of the jewel-like structure in higher dimensional space that creates the tropical zodiac. This jewel-like structure is intricate and exquisite like a beautifully cut precious stone. The first cuts of this gem are the tropical zodiac signs. Additional refinements to the jewel-like zodiac is created by relationships from the primary points of the first layer of the jewel, the zodiac sign cardinal points, in relationship to the galactic context in which our solar system is embedded.

As explained above, the tropical zodiac is formed out of the intersection points of the ecliptic plane and the equatorial plane. These ecliptic plane and the equatorial plane are created by the rotation of the Earth on its axis and the revolution of the Earth around the Sun. These two forms of Spin generate a zodiac. However this dynamic system of the Earth spinning on its axis as it revolves around the Earth is embedded in the larger context of the Earth's relatively slow wobble and the Earth's relationship to its "grandfather", the Galactic Center. The Earth's wobble on its axis is too slow to noticeably affect the relationship of the tilt of the Earth to the Sun; the Earth reaches its maximum tilt from the Sun around December 21 of each year and the length of the seasonal year would be affected only very slightly if the Earth was not wobbling in a 25,800 year cycle. However, the wobble of the Earth on its axis has a more obvious effect on the relationsip of the Earth to the fixed stars, including the Galatic Center. As noted above, the year 2225 within the context of the Great Year of 25,800 years is analogous to the date December 21 in a seasonal year of 365.25 days.

The tropical cardinal points are the key points of power in the tropical zodiac. As explained in the tutorial video mentioned earlier, the points Zero-Aries and Zero-Libra are condensed points that, in a sense, contain the power of the entire sky through a process of dimension reduction. The Zero-Aries point is also analogous to the Ascendant, where the Ascendant is essentially the Zero-Aries point within the context a cycle of one day rather than within the context of a cycle of 365.25 days. The Ascendant is the intersection point of the horizon plane and ecliptic plane and is similar to the the Zero-Aries point which is the intersection point of the equatorial plane and the ecliptic plane. The MC as the point of highest elevation of the equatorial plane in relationship to the Horizon plane and is analogous to the point of greatest southern declination of the Sun when it reaches 0-Capricorn and the point of greatest southern declination of the Galactic Center when it reaches 0-Capricorn. The angular house cusps, the cardinal points in tropical zodiac and the Galactic Center are the key players in a fractal-like structure of space at three different levels.

One of the most powerful geometric structures in astrology is an isosceles trapezoid or Isotrap as we call in in the system of astrology known as Vibrational Astrology. An Isotrap occurs whenever two pairs of planets are in the same angular relationship to each other. When this occurs there are two pairs of planets with the same angular distance so there is a double resonance. In geometry, this is the well-known fact that in an isosceles trapezoid the two sides are the same length and the diagonals are the same length. When these 4 points are planet positions in the zodiac circle this is evident in the fact that two pairs of angles are identical.

For any given three points there are three other points that make Isotraps. Thus, given any three points there are three other points that make extremely powerful resonating points with the three planets. In a natal chart three obviously important points are the Sun, Moon, and Ascendant. Therefore, the three extremely powerful resonating points are (1) Asc+Moon-Sun or Part of Fortune, (2) Asc+Sun-Moon or Part of Spirit, and (3) Sun+Moon-Asc which is rarely used in astrology but used by a few astrologers and called the Part of Redemption. The Arabic Part formula is actually the formula for finding these powerful resonating points, i.e., the fourth point of an Isotrap formed with the 3 given points.

If we take tropical Zero-Aries, tropical Zero-Capricorn, and the Galactic Center as three vitally important fundamental points in the geometry of space that relate our tropical zodiac to the context in which it is embedded within the galaxy, then Zero-Aries and Zero-Capricorn can be used as two power points in the tropical zodiac in relationship to the third point of the GC, which is the focal point of the galaxy. GIven these 3 points, we have these formulas for calculating powerful resonance points created by the relationship of the sacred geometry within our solar system in relationship to the galaxy: GC + Zero-Aries - 0-Capricorn, Zero-Aries + Zero-Capricorn - GC, and GC + Zero-Capricorn. Zero-Aries, of course = 0, and 0-Capricorn = 270, so the 3 formulas reduce to the following: GC-270, 270-GC, and GC+270. Adding 270 is the same as subtracting 90, and subtracting 270 is the same as adding 90, so these 3 formulas can be expressed as follows: GC+90, 270-GC, and GC-90. Using the GC position of 27 Sag 00 in the year 2010 we obtain these 3 points: 27 Pisces, 3 Aries, and 27 Virgo. Thus we have 3 powerful resonating points and two of the points are opposite to each other. Of the 3 resonating points, one is 90 degrees ahead of the GC, one is 90 degrees before the GC and there is one additional point, which in this case is 3 Aries. The two opposite points create an extremely powerful axis.

In the Middle Ages astrologers would sometimes use the Part of Fortune or Part of Spirit as an Ascendant point. The Arabic Parts (also known as Lots) were regarded as very special and powerful points. The 3 power points described in the previous paragraph are Arabic Parts that are formed by the relationship of the tropical zodiac to the Galactic Center. These arabic parts also can be used as starting points of a zodiac and the powerful axis square to the Galactic Center already has the required characteristics of an axis that is needed to establish the axis of a house system or zodiac.

The point 90 degrees ahead of the GC is a powerful resonating point that integrates the power of the solar system with the power of the galaxy. It is a point that connects us to a galactic perspective. It is the 0-Aries point of the sidereal zodiac! The calculation of the 0-Aries point in the sidereal zodiac is extraordinariy simple. It is just GC+90. For example, in the year 2010, the tropical GC position is 27 Pis 00 so 27 Pis 00 is the Zero-Aries point in the year 2010. Note that in the calculation above of the 3 resonating points for the year 2010 the 3 resonating points are 27 Pisces, 27 Virgo and 3 Aries. Tropical 27 Pisces is the 0-Aries point in the sidereal zodiac, the opposite point of Tropical 27 Virgo is the 0-Libra point in the sidereal zodiac, and 3-Aries is the is the sidereal position of tropical 0-Aries.

Rather than the sidereal zodiac being star-based, the sidereal zodiac is another layer of the sacred geometry of space that formed the 12 houses and 12 tropical zodiac signs. Note also that the tropical zodiac is sometimes regarded as a zodiac based on the seasons but it is a zodiac based on sacred geometry, and sacred geometry creates both the seasons and the tropical zodiac. Sacred geometry also is the foundation of the sidereal zodiac. Some astrologers may regard the Cochrane ayanamsha as very far-fetched and extremely speculative but this is true only if you do not regard sacred geometry and vibration as the only foundations of astrology, or if you do not consider the sacred geometry to be an exquisite and intricate jewel but instead assume that the sacred geometry is very simple and restricted to twelve divisions without very much additional sophistication, elegance, or complexity. One attractive feature of the Cochrane ayanamsha is that it is based on the idea that there is one underlying principle for both zodiac: sacred geometry. Sacred geometry has also been proposed by scientists as a foundation of many ideas in physics (although they don't call the jewel-like higher dimensional structure sacred) so these ideas move our ideas towards a theory of everything that is elegant and unified.


Although it may be disturbing that the Cochrane ayanamsha has a very different value from other aynamshas, a pleasing result is that the Cochrane ayanamsha agrees that we are near the end of an approximately 2,156 year Age of Pisces. According to our theory the tropical zodiac is the fundamental and most important zodiac. The sidereal zodiac is an additional layer in the intricate tapestry in which we live and this layer is a structure that connects our life to the level of the galaxy. This idea is the reverse of what has been assumed. It has been assumed that the astrological ages are based on the position of the tropical 0-Aries point in a sidereal zodiac sign but this idea is inconsistent with the model which we have built where the tropical zodiac is fundamental and primary. It is the placement of sidereal 0-Aries in the tropical zodiac that creates the ages. In the year 2010 sidereal 0-Aries is in the tropical sign of Pisces so we are in the Age of Pisces.

If it is true that the astrological ages are created by the movement of sidereal 0-Aries through the tropical signs, then the ages proceed in direction motion through the zodiac rather than retrograde motion, and in the year 2225 we enter the Age of Aries-Libra not the Age of Aquarius. The past 2,000 years have emphasized the Savior and the Virgon (Pisces and Virgo) and the next 2,000 years will emphasize honesty, integrity, and equality. In the next age gender discrimination and racism will end, and spirituality will emphasize the divnity of everyone and not just the enlightened.

We may feel disappointment if eventually it is found that the Cochrane ayanasha is correct and other ayanamshas are incorrect because this would mean that a great many astrologers have been deluded. However, this is only a possibility and despite the elegance of the Cochrane ayanamsha, an idea must be validated empirically and not just by theory. As noted earlier, it is also possible that there is more than one siderel zodiac. We can, however, also feel a sense of relief and fulfillment that a basis for the sidereal zodiac has been found, albeit a bit different from what was expected. The proposal of this paper that there is a sidereal zodiac and that there is an elegant beautiful basis for both the tropical and sidereal zodiac and all is based on sacred geometry and vibration preserves the spirit of the Vedic tradition and also of modern string theory in which vibration is fundamental to the nature of the universe. The poet in me would feel disappointed if the Earth's wobble and the changing pole stars over the course of the grand scale of the Great Year, and all of the efforts of great saints and sages like Sri Yukteswar to probe the depths of grand cycles of human development in the Yugas was all misguided. It would seem a grand waste of Mother Nature's work to leave the Earth's wobble as a merely mechanical function with no relevance to the drama of human history. As the physicist Richard Feynman emphasized, Nature is what she is and we do not get to decide, but nevertheless we can be delighted or disappointed in what we discover. As is invariably the case, these developments in model building and explorations into the nature of reality and our lives are delightful, albeit unexpected. My only hope, and it is only a hope as time will tell, is that these efforts and the great number of hours that I spent sorting through these ideas to finally come to a conclusion is a step towards greater understanding and at least a small contribution and step in the right direction of what Sri Yukteswar and others were investigating, rather than another blind alley that eventually leads to a dead end from which we must return back to continue our journey.

David Cochrane AUTHOR: David Cochrane