NavList:

There was a wonderful posting on the list (I think it was last year, could have been the year before) noting that the sun's true path was slightly below its theoretical one due to the moon's pull.   So the question became did the equinox occur when the sun's theoretical path crossed the equator or its actual path....

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From: Peter Hakel <pmh099@yahoo.com>
To: luabel@ymail.com
Sent: Friday, March 21, 2014 3:06 PM
Subject: [NavList] Re: Vernal equinox

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Declination is measured against the celestial equator - are you referring to precession and nutation?  Can you point me to H. Prinz's original postings?


Peter Hakel

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From: Bill B <billyrem42---.net>
To: pmh099---.com
Sent: Friday, March 21, 2014 2:01 AM
Subject: [NavList] Re: Vernal equinox

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On 3/21/2014 2:21 AM, Bill B wrote:
....As George H. might query,
>
My bad. Give credit where credit is due. Herbert Prinz, both in text and
graphically, illustrated the historic subtleties.

Risking censure for diverting the hot traditional-navigation
discussion-group topic from 21st century avionics and interpersonal
electronic communications, my question remains, "... measured against
exactly what?"

: http://fer3.com/arc/m2.aspx?i=127307

: http://fer3.com/arc/m2.aspx?i=127329