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    Re: Time of meridian passage accuracy
    From: Gary LaPook
    Date: 2009 Sep 30, 23:45 -0700

    "Ho" is the standard abbreviation pour les navigateurs anglophone for
    "observed altitude" or "height-observed." All corrections have been
    applied and it is the altitude to the center of the sun. Since the
    sights are taken with a bubble sextant the corrections that have been
    applied are index error, refraction and coriolis. No need for dip or
    Ho = la hauteur vraie.
    On Sep 30, 11:10�pm,  wrote:
    > Dear GL,
    > When you state : "and all sextant corrections have been applied so the 
    values stated are the observed altitudes", do you mean that the heights you 
    indicate have been corrected :
    > (1) just for "sextant" corrections, in which case when assuming that such 
    corrections have been made, we still need to go with Dip, Refraction, 
    Semi-Diameter and parallax corrections. What is height of eye then (for dip), 
    assuming that the refraction correction is supposed to be performed under 
    standard temperature and pressure conditions �?
    > or rather :
    > (2) already corrected for the remaining "height" corrections (listed 
    hereabove), so that the heights you published are to be considered as 
    "Geocentric" heights ?
    > I am asking because I am not quite familiar with the "Ho" indication you are 
    referring to. If you were specifying for example - if such were the case - 
    that the listed heights are "Geocentric", I would feel that such wording 
    would be totally - and internationnally �:-) � �- unambiguous.
    > Thank you for your Kind Attention and reply
    > Antoine
    > Antoine M. "Kermit" Couette
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