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    Stark Lunar Tables for LOP sight reduction
    From: Robin Stuart
    Date: 2011 Mar 13, 09:48 -0700

    I have by now spent many contented hours understanding and reproducing the values in the Stark Tables for clearing lunar distances. The tables are an interesting body of work with uses that go beyond just clearing lunar distances. For example, as well as the obvious refraction + semidiameter calculations for the Sun and Moon, the r&p column in Table 3 for Jupiter, Saturn and Stars provides a table of refraction corrections themselves. The exact parameters are not specified but p=1010mb, T=66F appears to give a good fit.

    In addition, the formulas used in the tables to clear lunar distances are closely analogous to those needed for LOP sight reductions. All Bruce Stark's tricks, such as the use of Gaussian logarithms, can then be exploited.

    The formula in the tables used to calculate lunar distances from the Nautical Almanac is the same as that needed for calculating altitude (actually zenithal distance).

    The formula for converting the measured distance to the true (geocentric) distance involves obtaining an expression for the difference in azimuths between the Moon and other body which closely matches the operations needed to compute azimuth.

    I have put together a spreadsheet that shows how to use the Stark Tables for LOP sight reduction. The spreadsheet contains instructions, in which I attempted to follow Stark's conventions and style, as well as a description of the underlying formulas. The spreadsheet is fully active and only requires that the relevant data be entered in the inputs section. Values that would be copied from the tables are calculated by the spreadsheet that provides a guide for manual calculations. The contents of this spreadsheet are also attached as a pdf file.

    Robin Stuart
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