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    Re: Where was the solstice?
    From: Antoine Couëtte
    Date: 2018 Jun 21, 12:34 -0700

    RE : Where-was-solstice-Howard-jun-2018-g42281

    Hello to all,

    IF the solstice is defined as "SUN apparent RA equal to 90°", then I do agree to John's Value to within less than 1 second of time, hence getting the same Latitude and Longitude on Earth. NOTE : Additionnal significant digits here on request  -:). This is pretty straightforward to determine since the Sun RA varies by + 156.0" / hour at this time of the year, and also because the final result is almost insensitive to the very small difference in DeltaT expected between us. I have used DeltaT = +70.8s which I trust as being excessive by almost one second of time.

    IF the solstice is to be defined as "SUN apparent declination maximum", then it is more delicate to accurately pinpoint. However I would reckon this moment as having happened about 5 minutes earlier than the one listed hereabove, which would yield essentially the same Latitude, but a Longitude about 1°15' to the East of the one previously indicated.

    Kermit

       
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