Mean Equinox J2000.0: Confirm Ecliptic Plane Intersection

[WildEnergy]

Hi

I can't find a clear answer to this anywhere.

Can anybody confirm that the ecliptic plane for J2000.0 intersects these 3 points:

a) center of mass of sun @ J2000.0
b) center of mass of Earth @ J2000.0
c) center of mass of Earth @ 20 March 2000 07:35 UTC

Experiments with Celestia seem to confirm this.

But I am confused by the phrase "Mean Equinox at Epoch J2000.0"

Also does anybody know where to find the official definition?
Looking around the IERS website - never seem to find the actual full answer.

 

[WildEnergy]

all this is deprecated now, as explained by this PDF:
http://syrte.obspm.fr/iau/iauWGnfa/wallace_com8_ga06.pdf"
the reason I could find no answer - is because there is no answer