> Polaris, the North Star, is often suggested for sundial alignment. This > fairly bright star is pretty close to north, perhaps a half a degree off the > polar axis, generally available in the northern hemisphere and easy to find > in the sky. > I hope this is useful for any of you interested in polar alignment of > sundials. Personally I prefer to use solar noon and a shadow stick. > > Roger Bailey > Walking Shadow Designs > N 51 W 115
Obtaining accurate polar alignment is a challenge. Even despite the best efforts, there is bound to be some error, no matter which method is used. I have written a program that can determine from 3 sundial readings exactly how much error there is in your polar alignment, and then tells you how to correct it. You can then repeat your measurements until your dial is aligned as well as possible. This method is the subject of an article in the upcomming June NASS compendium. The program (SundialAlign!) is available free at www.precisionsundials.com. Unfortunately, this method does not work well near the equinoxes, so you would have to wait until around May 1st to try it on your sundial. Bill Gottesman -
