Originally Posted by Eta C

We need to be careful in our terms here. Right Ascention is measured in an hour/minute/second system. A precession rate of 20 minutes of RA a year is way too fast. At that rate the entire sky would cycle around once every 72 years. The actual precession period is 26,000 years. That corresponds to 3.3 seconds of RA per year (or 50 arc-seconds if measuring in a degree/minute/second system). At that rate it takes 18 years to move one minute of RA and 1080 to shift one hour. Still, RichardR's estimate of 72 years of the solstices being close to the galactic/ecliptic intersection is about right. In that time, the precession is 4 min of RA, so if we define +/- 2 minutes RA as "close enough" we're about on.