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    Follow up to comments on March 22 Lunars
    From: Arthur Pearson
    Date: 2002 Mar 25, 22:29 -0500

    Gentlemen (and I hope at least some ladies):
    
    It is hard to keep up with the theoretical and practical comments that
    have been exchanged, but it is a welcome challenge. Some follow up
    remarks:
    
    1) Bill Noyce's advice on twisting the sextant knob in the same
    direction in all situations is well taken. I had not been given that
    instruction before but will practice it future.
    
    2) Bruce's "wrong way" tables convert from computed altitude to apparent
    altitude to allow the use of calculated altitudes in clearing lunars.
    Unless I am missing something, they don't allow one to "unclear" a
    calculated lunar distance. If he were willing to share the formulas for
    the wrong way tables, it would be possible to create a spreadsheet to
    derive periodic apparent altitudes from calculated altitudes, and from
    those periodic apparent altitudes, to calculate the apparent lunar
    distance, and then sextant distance as it would appear to an observer.
    This would allow examination of George's "parallactic retardation" over
    an extended period using hourly almanac data. I would be willing to take
    a run at this and share the data with the group.
    
    3) George suggested I share the intermediate values I came up with after
    I corrected the errors I had made in calculating GMT for my March 22
    lunar. Here they are in an abbreviated format that allows me to cut and
    paste out of my worksheet:
                    Deg.    Min.
    Sc              40      41.7
    Sa              40      42.8
    Mc              30      41.7
    Ma              29      53.2
    Moon R&P                48.50
    S R&P                   -1.06
    Moon aSD                15.88
    Da              99      4.2
    D               98      23.6
    D1              97      55.9
    D2              98      26.9
    
    GMT Obs 18:53:40
    
    4) George also requested additional series of lunar distances. I will
    submit a separate email with a Feb. 24 set of distances off Jupiter
    along with my results.
    
    Regards,
    Arthur
    
    
    

       
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