Hello yall: What I've been trying to do is to tell my sundial customers that there are four "magical" days of the year when their sundial keeps perfect Standard Mean Time. (The dials are already corrected for longitude and DLS Time). On these four days, they don't need a copy of the EOT to tell time. These are also the only days that a sundial can be set, without EOT corrections, using the time method.
>From what I've learned, with your help, is that these dates may change from year to year mostly due to leap year adjustments. This anual variation may be as much as 24 hrs. But the exact moment of the event, EOT=0, is absolute and occurs at the same time everywhere. The date, however, may be different due to longitudinal time zone differences. I guess what I need is the AVERAGE four dates for The United States. Do you think that it is ok to stick with: April 15, Jun. 14, Sep 1, and Dec 25 ? I can accept an error of about 1 minute (EOT=0 plus or minus 1), as my dials can only be read to about 1 min. EOT will be -1 min. tomarrow. Thank you all, John Carmichael Tucson
