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    Re: Bubble horizon altitude corrections
    From: Gary LaPook
    Date: 2024 Aug 29, 16:52 -0700

    Use the "horizontal parallax" values from the nautical almanac with this table. This table only has to provide values for horizontal parallax from 54 to 60 minutes sice that is the limit of changes due to distance changes from the earth to the moon. If you have the Air Almanac then you have a separate "Parallax in Altitude" table on each page based on the moon's horizontal parallax for that day which varies with the moon's distance.

    So, index error, and rerraction and parallax in latitude either from the attached table or from the Air Almanac

    gl

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    Dreisonstok-sextant-correction-tables-(1).pdf
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