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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 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:
> >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!
>
>Geoffrey
>
>
>
>
>
>: http://fer3.com/arc/m2.aspx?i=120607

   

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