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    Time Sight Problem: Joshua Slocum Lunar
    From: David Fleming
    Date: 2011 Mar 25, 13:30 -0700

    I have questions concerning the nature of the solution not proceedure.

    The noon meridian transit series is straight forward demonstrating the simple math required to extract Lat from these series of solar altitude measurements.

    The afternoon solar altitude, given Lat is by definition a LAT measurement. We do not need to know DR Lo at all to obtain this result.

    The afternoon lunar is an ideal sight to obtain Lo given that moon is most rapidly moving object in the sky and its near Prime Vertical position reduce erros in Lo attributable to measurement errors.

    What is troubling is the lunar sight produced a GMT of 23:50:48. How is that possible? Given assumed DR and measured altitude I can compute GMT but it has errors carried by the DR in it.

    So What kind of animal would the result be? It is Running since we are combining different times and an estimated position if it depends on DR, a Running Estimated Position?

    I'm guessing that Frank simplified the solution for our benefit. Is there a way to process sun and moon altitudes to extract GMT independent of DR? Are you going to tell us?

    Dave Fleming
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