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    Emergency navigation: a Nocturnal as the Local Siderial Time source.
    From: Tony Oz
    Date: 2016 Sep 1, 09:42 -0700

    Inspired by Francis:

    I recently improved the accuracy of my homemade nocturnal by increasing the size and adding vernias .(used for polaris latitude correction without tables). Also has simple bubble level to help keep things horizontal and perpendicuar.

    Francis, could you please describe your Nocturnal in more detail?

    • how do you deal with leap years (on the calendar scale)?
    • do you take into account the difference between the Earth rotation duration agains the Sun and the stars (on the hours scale)?
    • what is the accuracy of your local time results?
    • how do you obtain UTC from it (if you do)?

    Thank you very much!

    Regards,

    Tony

       
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