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    Re: Historical Lunars : take in account 'delta-T' or ignore it ?
    From: Paul Hirose
    Date: 2009 Dec 15, 13:51 -0800

    antoine.m.couette{at}club-internet.fr wrote:
    > Sorry for lazily selecting directly from my keyboard a sign which more 
    > or less looks like the "smaller than" sign. Certainly this is why your 
    > software interpreted my post as an HTML message. In the future, I will 
    > carefully choose all characters only from the Windows Characters list.
    I believe you typed the correct character (<), but something converted
    it to a character entity (<). The Windows Character Map probably
    won't prevent that problem. Fortunately I have written HTML so I know
    < means "less than".
    > Let me first try with the degree sign : � . Did it work this time ?
    Yes, perfect.
    > If I keep understanding correctly you consider that the great circle GC1 
    > which joins up both refracted centers is exactly the same as the great 
    > circle GC2 joining up the closest two points between both apparent limbs 
    > (because a sextant will - or is supposed to at least - measure exactly 
    > that angular distance alongside GC2 I would think). And from the sextant 
    > measured distance you add-up both refracted semi-diameters computed 
    > alongside GC1.
    That is correct, except the last sentence. I begin with the predicted
    unrefracted azimuths and altitudes, apply refraction, compute the
    separation angle, and subtract the refracted semidiameters. The result
    should equal the observed lunar distance. In effect, it's the same as
    what you wrote, just a different way to sequence the calculation.
    > LAST NOTE : Just to be to be sure, and since it was the first time I 
    > sent an attachment, did you see and could you read my post on the Cras 
    > Plotter [NavList 11145] ?
    I did not see it because I filter out all emails with attachments.
    That's a defensive move because some people attach large files which
    take too much time on my low speed connection. Of course if I'm
    expecting a file I will look for it.
    I filter out messages with attachments or HTML.
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