Working with Keplerian Elements & Deriving Vernal Equinox

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SUMMARY

This discussion focuses on the application of Keplerian Elements obtained from the JPL website to derive the Vernal Equinox. Key elements include the Semi-Major Axis (a), Eccentricity (e), Inclination (I), Mean Longitude (L), Longitude of the Periapsis, and Longitude of the Ascending Node. The user successfully calculates Mean Anomaly (MA), Eccentric Anomaly (EA), True Anomaly (v), and Radius (r) based on these elements, confirming the Vernal Equinox occurs around March 21. The user also notes the reference angle for the Ascending Node is approximately 270.02 degrees for Earth.

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Philosophaie
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I am working with the Keplerian Elements from the JPL web site.

a - Semi-Major Axis
e - Eccentricity
I - Incilination
L - Mean Longitude
long.peri. - Longitude of the Periapsis
long.node.or N - Longitude of the Ascending Node

http://ssd.jpl.nasa.gov/txt/p_elem_t2.txt

From this you can derive

MA - Mean Anomaly
EA - Eccentric Anomaly
v - True Anomaly
r - Radius
Equ - Vernal Equinox

All of this data revolves around the v=0 point or the Periapsis, the point where the elliptical orbit is the closest to the sun. Now from this point the Vernal Equinox can be derived. The Vernal Equinox occurs on about March 21 every year. When looking thru the Sun on 3-21 the constellation that you see is Pisces. At the angle (the Sun to Pisces from the Periapsis) is the basis of the reference angle for the start of the Ascending Node, I think. It comes out to be 270.02 for the Earth. The data seems to be coming out right, Equ+N+w+v=0 @ 12-21, Equ+N+w+v=90 @ 3-21, Equ+N+w+v=180 @ 6-21 and Equ+N+w+v=270 @ 9-21. I just want to know If I am way off or I am right on target.
 
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