Re: Anti-sundial

[Edley McKnight]

<x-rich>Steve,

Although there are a number of "sun compass" programs and physical dials around the simplest approach would be to use Karen Robinson's approximation to a ring dial using just one's fingers. I've tried it a number of times and it has always been within 10-15 degrees of pointing true north. Her article is in NASS Compendium issue of March 2002. The article is called "A “Digital ” Universal Ring Dial – More Time At Your Fingertips". Of course a universal ring dial itself would work better, but would be another thing that could be lost or left at home.

Hope this helps!

Edley.

Esteemed list...

My wife is a realtor who often wants to determine the direction a house is
facing. Being directionally impaired, and not having a car with a built-in
compass, she is usually at a loss. I had the idea, not especially original
or brilliant, of writing an anti-sundial for her Palm PDA. My idea is
that, given the time and approximate location and knowing the position of
the sun, we should be able to determine which way is North. I was thinking
of a program that would draw a compass rose and display a marker showing
the sun's position. She would then rotate the Palm until the marker
pointed at the sun and, voila, the rose would be oriented properly.
Accuracy of +/- 30 degrees is adequate. Any reason this won't work? And,
since I'm mathematically lazy, can someone tell me how to do the
calculation?

Thanks.


-

- </x-rich>