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    Updated Windows lunar distance program v.
    From: Paul Hirose
    Date: 2016 Jul 03, 21:34 -0700

    My Windows program to solve lunar distance navigation problems has
    finally been updated to eliminate the bug that prevented it from working
    under Windows 8. This was possible thanks to a rewrite of the supporting
    SofaJpl "astronomy engine" DLL. All the Fortran routines in SofaJpl have
    been replaced with C++ or C#, thereby fixing the Win 8 bug and
    eliminating some annoyances and limitations in the handling of JPL
    planetary ephemerides.
    This new release has not yet been subjected to all the tests listed at
    the Web site. But the two main tests — the Sun and Pollux lunars — are
    very good. I don't expect any problems with accuracy. To the contrary,
    the former version had a flaw (now corrected) in the deflection of the
    vertical computation.
    In addition to solving the classic lunar distance problem (one
    separation angle and two altitudes), the program can also
    • Determine time from lunar distance only, observed from a known location.
    • Determine time from a single altitude at a known location (a time sight).
    • Solve for position line azimuth and intercept.
    • Generate geocentric apparent position data, as in the Nautical
    Almanac, but with higher accuracy.
    • Calculate eclipse and occultation data. The program isn't optimum for
    this application — you must find the contact times by trial and error —
    but the results are accurate. A few years ago I used the previous
    version to analyze a near occultation observed from Alexandria in the
    3rd century BC. Recently I recomputed the event with more appropriate
    software and found the differences insignificant.
    Available bodies are the Sun, Moon, all planets (including Pluto) and
    all stars to magnitude 3.0. Data for any star not in the built-in
    catalog may be entered by hand.
    I would appreciate any feedback regarding success or failure in getting
    the program to run. Include your Windows version. One user with ver. 7
    reports his antivirus software blocks the lunar program for an unknown
    Speaking of security, installation is improved from the previous
    version. The "installer" is just a .zip file, which you extract into the
    desired directory. Thus the software will install into a Windows limited
    account. You don't need system manager privileges, and for security I
    don't recommend installation via a system manager account.

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