RE: equinox solar declination

[Tom Kreyche]

John,   One of the best places to get this info is from the U.S. Naval Observatory web site. They have an online version of their MICA (Multi-year Interactive Computer almanac) which is not as complete as the CD version but perfectly adequate. Go to their data services at http://aa.usno.navy.mil/data/ and pick "Web Version of MICA."   I don't have your exact lat/lon/height but the following figures are probably pretty close. This is based on topocentric location, you can also get geocentric and a variety of other information, and change the intervals for running the data.   Tom                                          Sun                                                                                                                                                 Apparent Topocentric Positions                                                True Equator and Equinox of Date                                                                                                                        Location:  W111o00'00", N32o00'00",  1000m                                     (Longitude referred to Greenwich meridian)                                                                                                      Date        Time      Right Ascension     Declination        Distance               (UT1)                                                                       2001 Sep 22 12:00:00.0     11 58 21.029     +  0 10 42.14      1.003632643    2001 Sep 22 13:00:00.0     11 58 30.039     +  0 09 43.76      1.003611516    2001 Sep 22 14:00:00.0     11 58 39.014     +  0 08 45.37      1.003590206    2001 Sep 22 15:00:00.0     11 58 47.957     +  0 07 46.97      1.003569358    2001 Sep 22 16:00:00.0     11 58 56.869     +  0 06 48.58      1.003549582    2001 Sep 22 17:00:00.0     11 59 05.755     +  0 05 50.18      1.003531417    2001 Sep 22 18:00:00.0     11 59 14.620     +  0 04 51.78      1.003515291    2001 Sep 22 19:00:00.0     11 59 23.474     +  0 03 53.38      1.003501494    2001 Sep 22 20:00:00.0     11 59 32.324     +  0 02 54.97      1.003490156    2001 Sep 22 21:00:00.0     11 59 41.180     +  0 01 56.57      1.003481239    2001 Sep 22 22:00:00.0     11 59 50.049     +  0 00 58.16      1.003474540    2001 Sep 23 00:00:00.0     12 00 07.858     -  0 00 58.66      1.003466253    2001 Sep 23 01:00:00.0     12 00 16.808     -  0 01 57.07      1.003463606    2001 Sep 23 02:00:00.0     12 00 25.792     -  0 02 55.47      1.003461135    2001 Sep 23 03:00:00.0     12 00 34.809     -  0 03 53.88      1.003458196    2001 Sep 23 04:00:00.0     12 00 43.858     -  0 04 52.29      1.003454177    2001 Sep 23 05:00:00.0     12 00 52.933     -  0 05 50.70      1.003448540    2001 Sep 23 06:00:00.0     12 01 02.028     -  0 06 49.11      1.003440858    2001 Sep 23 07:00:00.0     12 01 11.136     -  0 07 47.52      1.003430841    2001 Sep 23 08:00:00.0     12 01 20.247     -  0 08 45.94      1.003418361    2001 Sep 23 09:00:00.0     12 01 29.354     -  0 09 44.36      1.003403454    2001 Sep 23 10:00:00.0     12 01 38.447     -  0 10 42.77      1.003386326    2001 Sep 23 11:00:00.0     12 01 47.519     -  0 11 41.20      1.003367330    2001 Sep 23 12:00:00.0     12 01 56.564     -  0 12 39.62      1.003346948                        -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]On Behalf Of John Carmichael Sent: Friday, September 21, 2001 6:53 PM To: sundial@rrz.uni-koeln.de Subject: equinox solar declination Hi all:   I'm getting this message out a little late, but tomorrow on the equinox,  I'd like to check the solar declination of the nodus's shadow. (Of the Flandrau heliochronometer). I want to see if the center of the shadow is centered exactly on the 0 degree line at the exact moment of equinox.   My astronomical calendar says that the equinox occurs here (in Tucson AZ) at exactly 4:05 pm.  But since the declination is changing so quickly this time of year, I'm wondering if the shadow will be exactly on the 0 dec. line in the morning too.   Does anybody know what the solar declination is at around 9:00 my time?  (6 hours and 55 minutes before the actual equinox).  I wonder if I'll be able to detect this small amount?   Thanks  John   John L. Carmichael Jr. Sundial Sculptures 925 E. Foothills Dr. Tucson Arizona 85718 USA   Tel: 520-696-1709 Email: [EMAIL PROTECTED] Website: <http://www.sundialsculptures.com>