CardinalDirections uses Jean Meeus' formulas from "Astronomical Algorithms." I ran your [Patrick Powers] numbers through NASS's "The Dialist Companion." It gives the sun east at 7:32:33 AM (3 second difference), south at 1:01:20 PM (1 second difference), and west at 6:30:40 PM, a 3 second difference. I have no experience with WinEphem, and can not explain the large differences. CardinalDirections calculates the proper Eot and declination for each cardinal direction, and does not assume the noon value as the day's average. Selecting the correction for refraction did not change these values at all, which makes sense to me. I am not an expert on the effect of refraction, but it seems to me that it effects only the sun's altitude, and not its azimuth at all. The Cardinal Directions are strictly azimuthal measurements. I wonder if the problem with fonts getting crowded on some people's computers has to do with my selection of MS sans serif. I will change the font to Arial, which I think is more universally present on people's computers, and reissue CardinalDirections in a few days. I designed it to be viewed at 1024x768 screen resolution, forgetting that may not work for all users. I will also add Declinations and EoTs, as suggested by Fer. -Bill
In a message dated 8/28/2003 3:10:50 PM Eastern Daylight Time, [EMAIL PROTECTED] writes: > > Yes, the boxes for W and E of Greenwich are apparently 'merged' a little, > though the times for the Greenwich meridian and Lat 52 degs seem the same > whether E or W is specified However, times of transit of the sun on 28th > August 2003 at Greenwich and at Lat 52 degs are given as 13:01:21 but > WinEphem gives it as 13:03. I am not sure which is correct. (For ref: > times for East (given as 07:32:36) are 07:34:10 on WinEphem and times for > West (given as 18:30:37) are 18:31:51 on WinEphem. > -
