Friday, April 04, 2008

Default Ayanamsa in Jhora 7.1b2

From: Narasimha P.V.R. Rao <>
Date: Wed, Apr 2, 2008 at 6:52 AM
Subject: Re: [jhora] Default Ayanamsa in Jhora 7.1b2


Yes, this was deliberate.

In regular ayanamsa implementations, the two-dimensional plane onto
which planets are being projected for the purpose of finding
longitudes is *oscillating*. The plane in use at birth and the plane
in use in the Tithi Pravesha chart of a year later are different. When
we are trying to fix the starting point of the zodiac, does it make
sense to have the "plane of zodiac" vary from day to day?

Vishnunabhi plane chitrapaksha ayanamsa is a new addition in JHora
7.1. It is essentially Lahiri ayanamsa only, but takes a fixed mean
plane. Thus, when we find planetary longitudes at birth and in an
annual Tajaka/Tithi Pravesha chart later, the same fixed zodiacal
plane is used to project planets in both cases.

It is more consistent and logical.

This makes very little difference in natal charts (unless a planet is
on a border), but makes a considerable difference in the Tithi
Pravesha charts. TP Time can change by 5-10 min and lagna in some
divisional charts may change in TP charts. Based on my experiments, I
am convinced that this works better than the regular Lahiri

As the author of JHora, I put the defaults that I believe give better
results to people. So I made this fixed plane Lahiri ayanamsa
variation the new default. Sorry for any inconvenience.

Best regards,
Do Ganapathi Homam Yourself:
Free Jyotish lessons (MP3):
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Sri Jagannath Centre (SJC) website:

----- Original Message -----
From: pushya
Sent: Tuesday, April 01, 2008 6:55 PM
Subject: [jhora] Default Ayanamsa in Jhora 7.1b2


Default Ayanamsa in Jhora 7.1 = Lahiri (Chitrapaksha)
Default Ayanamsa in Jhora 7.1b2 = Vishnu-nabhi Plane (Chitrapaksha)

Is this a deliberate change? If yes, could you kindly explain your
rationale for doing so?

Thank you.

Best Wishes,

Brihaspati Gayatri, Vishwamitra/Gaathina Rishi Rig Veda 6.62.6