There's been so much discussion about equinoctial precession on this list that I hope this question is not too far off target:
"Precession of the equinoxes" means the earth's rotational axis is precessing like a tilted top (one revolution every 25,000 years or so.) Can someone help me with the name of the axis (vector, whatever) that the earth's axis precesses _about_? And the real question: is this "central" axis perpendicular to the ecliptic? (I.e. throughout the Great Year, is the earth always tilted 23.5 degrees from the ecliptic?) Thanks. Rory Sellers P.S. There was a bunch of "shortest day/earliest sunset" discussion posted a while back, some of which was initiated by me. (It has to do with the tilt of the analemma.) I'll be posting a summary soon (other folks have also emailed me on this subject and I wanted to put something out for everyone -- sorry it's taken so long).
