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    Re: Angular Distance Between Stars By Camera and Sextant
    From: Paul Hirose
    Date: 2012 Sep 17, 20:49 -0700

    Marcel Tschudin wrote:
    > Thanks, Paul, for your code. May I ask you where you obtained for the stars
    > the high precission epoch 2000 coordinates from ?
    I'm surprised you could read the message. In the copy of my own message
    received by email, the link to the file gives a "page not found" error
    message. And when I view it on the Web in Firefox, there seems to be an
    extra character between every character of the source code. In IE, the
    source code looks clean, but with horrible narrow margins. And the link
    to the file still doesn't work. Next time, instead of attaching a file,
    I'll just say, "anyone who wants the source code, please ask via email."
    My star data came from the SIMBAD astronomical database:
    The separation angle program illustrates an unfortunate design flaw in
    the constructor for the Star class. With few exceptions, throughout
    SofaJpl I use radians, AU, and days as the units of measure. This
    enables a programmer to easily use the output of one routine as the
    input of another. But in the case of the Star constructor, it forces you
    to convert the usual measure of proper motion, milli arc seconds per
    Julian year, to radians per day. Radial velocity is even worse. You must
    convert km/s to AU/day.
    Generally, consistent units are a good thing, but here I should have
    compromised. The next release of SofaJpl (now in work) will fix that,
    and several other annoyances.
    I filter out messages with attachments or HTML.

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