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    Re: Zodiacal coordinates
    From: Robert H. van Gent
    Date: 2012 Sep 17, 07:51 +0000

    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 suspended.
    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 Kolbe
    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:
    >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

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