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    Re: getting GHA from MICA
    From: Paul Hirose
    Date: 2014 Mar 20, 21:08 -0700

    Sean C wrote:
    > I meant to ask which program you were referring to in your earlier post. I 
    found it and am going to play around with it today.
    If you mean Tinyac, it's more a general purpose almanac than a celestial
    nav program. My later program, Lunar3, is better for navigation. It's
    primarily for lunars, but will also compute altitude intercepts. Some
    advantages over Tinyac:
    Built-in star catalog (Hipparcos 2 data) complete to mag. 3. Any star
    not in the catalog may be entered manually as in Tinyac.
    Automatic delta T feature has unlimited range via a combination of
    lookup table and polynomials. No more error messages whining that the
    date is out of range, forcing you to supply delta T.
    The observed limb may be selected, for automatic semidiameter correction.
    If desired, a dip correction will be applied.
    Improved atmosphere and refraction models include effect of humidity.
    Tinyac's refraction dincontinuity (where it shifts to the low altitude
    formula around 15°) does not exist in Lunar3.
    Automatic solution of time sights and lunars.
    Compensation for deflection of the vertical is implemented correctly.
    Tinyac gets the altitude right, but not azimuth.
    Tinyac does have a more comprehensive selection of coordinate systems. A
    few days ago I needed a body's azimuth expressed in sexagesimal hours,
    and zenith distance instead of altitude. That's easy with Tinyac.
    Aside from the issues noted above, the programs are equally accurate.
    I filter out messages with attachments or HTML.

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