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    Re: Possible limitaion for lunar distance measurement
    From: Frank Reed
    Date: 2009 Feb 27, 16:37 -0800

    Kent, you wrote:
    "in this manual it is stated that it is only possible (or feasible) to use the 
    lunar distance method if the distance is between 70 and 110 degrees. "
    Historically, this is generally the case. But the reasons are practical, not 
    mathematical. Mostly, the Sun was the "other body" for lunar observations. 
    And the results were generally better when the Moon was around first or last 
    quarter which would be when the distances were in the range you gave: 90 
    degrees, plus or minus twenty. You would have three or four days to shoot 
    lunars twice a month. In practice that was enough. 
    By the way, one should take comments on lunars from those later years (like 
    1906) with a grain of salt. Lunars were entirely obsolete at sea, and some of 
    the textbook advice from that era was muddled.
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