Response to a paper seeking to establish a Sidereal Indian Zodiac

I published my article explaining that the original Indian zodiac is tropical (not sidereal as is currently in use).

Today a rebuttal was published.

Here is my reply to that rebuttal.

Tale of Two Zodiacs Reply

Dear Antardwipa Dasa and Shyamasundara Dasa,

Respectful thanks a well written and knowledgeable article. I will reply to a few points.

You expressed uncertainty about my phrase “center of space.” I use that phrase to refer to the point at which the ecliptic intersects the equator, providing a “center” for observational space.

The fact that there are not 12 equal-sized constellations among the stars is only one of several observations depreciating the concept that the 12 signs are intrinsically stellar. But even so, you proceeded on with your article without offering any specific counterpoint to this particular observation.

I agree that the rashi system (12 sections of 30 degrees) can be, and often is, abstracted to a mathematical principle of circular geometry, including the measure of sidereal phenomenon. However, the actual rashi themselves are intrinsically tropical (i.e. defined with reference to solstice and equinox) as per Surya Siddhānta 14.7-10 and the Puranas viz. Bhāgavatam 5.21.2-6.

Thus SS 1.28 states that such a system of seconds, degrees, signs, etc. can be used to measure sidereal space. But SS 14.7-10 makes it explicitly clear that the 12 signs themselves (not as mathematical abstractions, but the signs themselves) are tropical. SS 1.28 does not say that the signs are sidereal, merely it states that 12 divisions of 30 degrees is used to measure sidereal space. Thus I agree that both tropical and sidereal space can be measured in 12 30 degree sections. However, the origin of the 30 degree system is tropical – and thus the 12 30 degree signs are inherently tropical, although they have sidereal mathematical application.

I agree with and appreciate your statement that certain calculations (declination, rising signs, etc) are impossible to make without a tropical zodiac.

You make an interesting statement that planetary longitude is not included among the tropical calculations indicated in Surya Siddhānta. My reply:  (a) As you noted, the Siddhānta uses the word “etcetera” (adhikam) in its list of this to be tropically figured. (b) Planetary positions amongst the sidereal nakṣatra is very important, in fact far more important to the original indigenous Vedic astrology, than planetary positions among the 12 signs.

I agree that calculations of planetary revolutions per Surya Siddhānta are done with reference to Revatī, and that these reference points are observably fixed and stable. As you noted, this data is calculated first (in chapter 2), and then the lagna is calculated tropically (in chapter 3). If one wants planetary positions in reference to the nakṣatra, there is no further work to be done. If one wants the sidereal location of the lagna, the ayana must be subtracted from it. If one wants planetary positions in reference to the rashi (not as mathematical sections, but as actual rāśi themselves, divisions of space relative to the equinox), one must add the ayana to the previous calculations.

You quoted Bhāgavatam 5.22.2, but I feel you have misrepresented. It does define the planets moving differently than the signs and nakshatras. However, it does not state that the signs and nakshatras do not move with respect to one another.  This is an implication which you infer, it is not in the text itself.

It is misleading in the extreme to say that 5.22.2 gives a sidereal “definition” of the zodiac signs. A definition has already been given in 5.21.2-6 (and that definition is tropical). Definitions are explicit. They are not analogies. Furthermore, your inference from the analogy certainly does not qualify as a “definition.”

5.22.5 explains that a solar month is equivalent [not identical] to 2.25 nakshatras. Sripad Vijayadhvaj Tirtha is from the 15th century and explained this according to the prevalent custom of his time.

Varaha Mihira also spoke accurately of the correlation of stars and signs extant at his time. As he pointed out, the size of a navāmśa and the size of a nakṣatra pada are identical, and therefore the size of a rashi equals 9 nakṣatra pada.

I agree that Varaha Mihira was aware of the distinction between the tropical and sidereal chakra. I believe the confusion amongst Indian astrologers gradually arose over the several following centuries.

Your article was well written and researched. Thank you for the excellent effort. In it you have clearly demonstrated that 30 degree units called rashis can also be used to make sidereal measurements. However you failed to counter-argue the fact that rashis by definition are inherently tropical, as presented in my argument (

If this discussion of the zodiac helps us remember Krishna it is useful. Since you are both, Syamasundar and Antardwipa, dear servant of the servant of Krishna, my hope is that the dust of your feet will always be falling towards my lowered head. Please forgive the academic nature of discussion in which this person speaks up with an equal voice in a spirit of healthy debate.

Hare Krishna.

Your servant,

Vraja Kishor das