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    From: Mike Burkes
    Date: 2010 Jan 29, 12:37 -0800
    Hi Richard, the "d" from the Almanac refers to the daily difference of the declination and is noted as "d value" to be entered in the "Increments and Corrections" table at rear of Almanac. The d correction is the desired number.  I believe Table 5 of HO 249 is an interpolation table and I am not familiar with it. I have Mary's book but cannot seem to find her reference to Table 5. In essence the "d" values of NA and 249 are unrelated. HTH and the Nav L folks are extremely knowledgable and feel free to ask away.
    Mike Burkes

    > Hello. I am living in Hot Springs, Arkansas, and am studying
    > celestial on my own. Have several books, including Bowditch.
    > I am unclear about the so-called "d correction." It seems the d
    > number in the dailt pages of the Nautical Almanac should really
    > be called a "d factor" or something similar. Mary Blewitt's
    > book says to use this d factor to get into Table 5 of H.O. 249.
    > My confusion stems from no one else mentioning Table 5 (except
    > H.O. 249 itself).
    > Can/would someone explain to me, at the 8th grade level, about
    > the d factor for sun, moon and planet shots.
    > Thanks in advance. E-mail is fine (dickbash[at]bashlaw.com). You
    > have a fine resource here. Hope I am accepted as a list member.
    > Regards,
    > Richard Bash
    > Hot Springs, AR

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