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    Re: Sidereal Hour Angle vs. Right Ascension
    From: N S Gurnell
    Date: 2005 Aug 19, 18:11 -0700
    I was navigating British passenger ships in 1949 and had to buy the American Nautical Almanac to get the GHA's and use Ogura's or H.O. short method tables.  n.s.gurnell, Victoria.B.C.

    Robert Eno <enoid@NORTHWESTEL.NET> wrote:
    I was looking through some old almanacs over the weekend and noted that in the 1940's at least, the almanac provided celestial coordinates in terms of right ascension, in hours and minutes.
    Can anyone tell me at what point in time navigators moved from using right ascension to sidereal hour angle for reckoning celestial coordinates?  Why was this done?
    My first guess is that SHA is easier because one does not have to reckon with hours and minutes but instead, uses the more familiar degrees and minutes. Nevertheless, this is the system that I learned so it would naturally appear to be easier.

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