Q: New Year

[Girish Beeharry]

Hi,

>I'm still not sure the indology list is the right forum for this discussion,
>but anyway: the northern and southern courses of the sun (the ayanas) are
>not really related to the rAs'is; they are related to the summer and winter
>solstices, which no longer coincide with the sidereal saMkrAntis. Any
>paNDita worth his salt surely knows this. Like the equinoctial points, the
>solstice points are slowly regressing through the zodiac; in a few hundred
>years, they will coincide with dhanuH- and mithuna-saMkrAntis, respectively.


You are right, the Indology list is not really meant for this discussion.
The ayanas are related to the raashis in the sense that the raashis 
provide one of the axes of reference for the motions of the grahas. The 
grahas describe curves whose trajectories are projected on the celestial 
sphere. Therefore, as we are dealing with a motion in three dimensions, 
we need two other axes of reference to describe completely how grahas 
move. One of these axes is found by doing some maths on the points where, 
say the Sun, starts the uttarAyaNa & the dakshinAyana. Therefore these two
concepts, ayanas and rAshis, are intimately connected. The third 
reference is trivial; as we are working on the surface of a sphere, we do 
not have to worry about distances.

The whole problem of the ayanAMsha lies in defining accurately the 
precise set of spherical rotations that will map the sidereal system onto the
tropical one.

I am sorry if this sounds like sci.astro.research! :-) Members wishing to
continue this interesting discussion are invited to do so privately.

Bye,

Girish Beeharry