More On the Ayanamsa Issue

[Guest guest]

Namaste friends,

 

As I mentioned before, I have experimented with a variation of Lahiri ayanamsa

that uses a fixed zodiacal plane. Normally, people use the Sun-earth plane as

the zodiacal plane and it has a wobbling motion. In other words, longitudes at

different times are measured on a different plane, as the plane wobbles with

time. When we are fixing the starting point of the zodiac, does it make sense to

have a plane that is not fixed??

 

The entire solar system has a rotation too (around a point that we refer to as

" Vishnunabhi " - navel of Vishnu). The equatorial plane of this rotation is very

stable and has no wobbling motion. It makes excellent sense to use this plane as

the zodiacal plane instead of a wobbling Sun-earth plane.

 

When I used this fixed plane instead of wobbing Sun-earth plane, the longitudes

of planets change by a few arc-sec and sometimes by a few arc-min. However,

unlike in regular ayanamsa changes, the change in different planets is

different. Thus, (Moon-Sun) differential changes differently at different times.

This means that times of Tithi Pravesha (Sun-Moon angular return) can change by

several minutes compared to regular Lahiri ayanamsa. This changes the lagna in

several divisional charts of TP in almost all years.

 

I compared the divisional charts of TP between the two ayanamsas and concluded

that the fixed plane version is more consistent. I use that ayanamsa myself.

 

* * *

 

However, one thing still troubled me. Though the choice of the plane is very

logical and not really arbitrary, the choice of the zero point has a little

arbitrariness. I mean, Chitra at 180 deg is logical. But we were taking Chitra

at 180 deg on a particular date. That is arbitrary. At later dates, Chitra may

be slightly away from 180 deg due to the slow star motion.

 

It is possible to define the ayanamsa such that Chitra is at 180 deg at all

times, i.e. slow motion of star is factored in.

 

This causes only a few arc-seconds of difference in the longitudes and it

affects all planets uniformly. Hence it has no impact on TP times (Moon-Sun does

not change as both Moon and Sun change by the same amount). It cause changes in

divisional charts only in border cases that are anyway susceptible to very minor

birthtime errors. Thus, this difference is mostly of academic interest and the

practical implication is very little. On the other hand, the practical

implication of the previously mentioned use of solar system rotation plane

(already available in JHora 7.2) is huge. It changes all TP charts (not just

border cases).

 

Nevertheless, I think the arbitrariness should go. Fixing ayanamsa based on a

specific date is arbitrary. Thus, I have modified the ayanamsa to place Chitra

(Spica) star at exactly 180 deg always. The starting point of the zodiac is

fixed in such a way that Chitra star is always at 180 deg exactly and the plane

of the zodiacal plane is fixed to the solar system rotation plane around

Vishnunabhi.

 

In my mind, this is very logical, consistent and not arbitrary. Neither the

plane nor the starting point has any silliness built in.

 

When I made this change in the ayanamsa I am using, I see no impact on TP charts

and all my previous analysis still holds. However, to be more logical and remove

arbitrariness from my work, I have switched to this ayanamsa. I made my final

decision.

 

I will make it available in the next JHora release.

 

For the benefit of those who dislike the fixed Vishnunabhi plane (why???? why

use a fixed starting point when the plane itself is not fixed?????) and want to

stick to the regular wobbly Sun-earth plane, I will add another various of

Lahiri ayanamsa. This will also place Chitra at 180 deg always, but on a

wobbling plane instead of the fixed Vishnunabhi plane.

 

I will make this release by the end of September. I hope that the serious

researchers of astrology will take advantage of this.

 

* * *

 

Mooladhara chakra represents bhu loka - the earthly realm of consciousness.

Other chakras represent higher lokas - the higher spiritual realms of

consciousness. While the 0 deg of Aries contains the head of kala purusha, i.e.

sahasrara chakra, it is the 180 deg point that contains mooladhara chakra. The

top seven and bottom seven chakras/lokas are in the two halves of the zodiac.

From this point of view, it is very logical to base the zodiac from 180 deg

point, i.e. Mooladhara chakra.

 

While the people who fixed Lahiri ayanamsa got it mostly, things like factoring

in the star motion and fixing the zodiacal plane were left out.

 

Best regards,

Narasimha

 

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