Hi Bill, Nice program and useful for diallists. Thanks for sharing this with us.
Couldn't you give an output for the EoT and the sun's declination too? That also would be helpful. Is the atmospheric refration incorpurated in the calculations? Not of importance for the sun due south or north but it is for the sun east or west. In the list of the time zones you write: GMT 0hrs Eastern European time, Greenwich GMT +2hrs Western European Time Eastern and Western should be reversed. Best wishes, Fer. Fer J. de Vries De Zonnewijzerkring mailto:[EMAIL PROTECTED] http://www.de-zonnewijzerkring.nl Home mailto:[EMAIL PROTECTED] http://www.iae.nl/users/ferdv/index-fer.htm Eindhoven, Netherlands lat. 51:30 N long. 5:30 E ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[email protected]> Sent: Thursday, August 28, 2003 7:15 PM Subject: Cardinal Direction Software > I just finished writing a tidy little program that calculates when the sun is > exactly south (or north), east and west for any given date and location. I > wrote it to help mark a cardinal direction for laying out analemmatic dials, > but it can help orient any sundial. Using the vertical string method, an east > west line is much easier to mark than a north south one, because the sun is > lower and so the shadow stays sharp over a longer length. > > Of course, an east west shadow can occur only in the summer half of the year > for people outside the tropic zones (most of the folks on this list). For > people within the tropic zones, the an east west shadow will not form near the > summer solstice either. And for the unfortunate sundialist who lives on the > equator, an east/west shadow can occur on only 2 days of the year--the equinoxes. > > Download CardinalDirections.exe from www.precisionsundials.com/software.htm, > and let me know what you think. > > -Bill Gottesman > - > -
