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    Re: Zodiacal coordinates
    From: Robert H. van Gent
    Date: 2012 Sep 17, 10:01 +0000

    Thanks Geoffrey for (re-)introducing me.
    Yes, I did confuse you with George Huxtable with whom I indeed corresponded in 
    the past and also had the pleasure of meeting at the 2006 NMM conference.
    However, although I am interested in celestial navigation and other things 
    maritime, I am (alas) not an active sailor.
    I am looking forward in joining some of the discussions on this list.
    Rob van Gent
    -----Original Message-----
    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Geoffrey Kolbe
    Sent: 17 September 2012 10:36
    To: Gent, R.H. van (Rob)
    Subject: [NavList] Re: Zodiacal coordinates
    Hello Rob
    I remember you well, welcome back.
    By way of (re)introduction for newer members, Rob is an acknowledged expert on 
    delta-T and the intricacies of UTC, UT1, leap seconds and all that goes with 
    it. When the subject of leap seconds comes around again, as I am sure it 
    will, I look forward to Rob giving us the benefit of his profound knowledge 
    on the subject.
    Rob is also active historian of astronomy in general, and an active sailor too, as I recall.
    I well remember Rob's talk on the tobacco boxes of Pieter Holm, given to the 
    National Maritime Museum symposium on navigational instruments back in 2006.
    George Huxtable (with whom I think you have confused me Rob,) is unfortunately is no longer with us.
    Geoffrey Kolbe
    At 08:51 17/09/2012, you wrote:
    >Hi George,
    >I agree - my claim that it was an astrological website was perhaps too 
    >hasty. I got this impression from the astrology adverts appearing in 
    >the bottom-right corner.
    >It is indeed better described as a website useful to both astronomers 
    >AND astrologers.
    >I note that the adopted delta-T value for now (71.7 secs) is slightly 
    >too high - a value near 67 secs would be more accurate, though this 
    >difference would only affect the moon's longitude by a few arcseconds.
    >To the older list members I should perhaps explain that I am not really 
    >'new' to this list. Many years ago I also contributed to this list but 
    >when I stopped receiving postings I assumed that the list had been 
    >I only recently discovered that the list still exists (and is also very 
    >much alive).
    >Rob van Gent
    >-----Original Message-----
    >From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Geoffrey 
    >Sent: 15 September 2012 10:24
    >To: Gent, R.H. van (Rob)
    >Subject: [NavList] Re: Zodiacal coordinates
    >At 15:16 14/09/2012, you wrote:
    > >Hi,
    > >
    > >I am new to this list but perhaps I can help.
    > >
    > >The site you have visited is an astrological website and the 
    > >celestial positions are given according to astrological conventions.
    > >
    > >The first number is indeed the degree, followed by the zodiacal sign 
    > >(Aries starts at 0, Taurus at 30, Gemini at 60, etc.) and then the 
    > >number of arcminutes and arcseconds. The positions are ecliptical and 
    > >appear to be tropical.
    > >
    > >The R found at the end of some longitudes indicates that the planet's 
    > >motion is retrograde (astrologers find this very important).
    > >
    > >I hope that this helps.
    > >
    > >Rob van Gent
    >Well Rob, this is an ephemeris which is obviously meant to be used for 
    >historical research as the validity period is 1600 to 2100.
    >Astronomers at the start of that era would certainly recognize this 
    >format for ecliptic longitudes, which is still used by astrologers 
    >today, as you correctly say. And today, astrologers do not have much 
    >use for ecliptic latitudes (they never did) and most astrologers would 
    >probably not know a Right Ascension if it hit them between the eyes. 
    >Right Ascension today is (I think) only used by astronomers. I would 
    >conclude that this is actually an astronomical almanac, formatted to be 
    >useful for historical research.
    >As for it being as astrological website, I struggle to actually find 
    >the word "astrology" anywhere on the website!
    >View and reply to this message: http://fer3.com/arc/m2.aspx?i=120607
    View and reply to this message: http://fer3.com/arc/m2.aspx?i=120629

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