Hi Art (and other list members) I guess getting within 6 minutes of accuracy isn't all that hard after all. With only four years of observations, you get a year of 365.25 days, or 365 plus 6 hours. This puts you within 12 minutes of accuracy, since one source I've found says the exact value over 365 days is 5 h, 48 min, 43 sec. So with a few centuries of observations, it would be possible to get closer.
Al Pratt
