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    Re: Need Help w/ Ageton method...
    From: William Allen
    Date: 2003 Mar 3, 12:57 -0800
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    I don't have my Ageton book in front of me (is it Pub 211? or 213?) because I am traveling, but I think I remember the terminology.  This is my favorite sight reduction method and I use it a lot.
     
    R is the "artificial" arc that is dropped from the celestial body to intersect as a perpendicular the co-latitude of the observer.  Ageton, like many others, decided to solve the oblique navigational triangle by dividing it into two right-angled spherical triangles with this perpendicular.  (Others dropped perpendiculars from different points as well.)
     
    You don't actually need to write down R to solve for intercept or azimuth, just look it up in the tables from its A value and then immediately write down its B value.  As you probably know, this B value is a log secant (the A value is a log cosecant) multiplied by 100,000.  The B value for arc R is then added to the A value from declination of the celestial body.  This sum gives you a new A value that you look up in the tables and right down as K.  And the rest just follows the rules ...
     
    Hope this helps.
     
    Regards,
    Bill Allen
    -----Original Message-----
    From: Navigation Mailing List [mailto:NAVIGATION-L{at}LISTSERV.WEBKAHUNA.COM] On Behalf Of HGWorks - Phil Guerra
    Sent: Sunday, March 02, 2003 7:18 PM
    To: NAVIGATION-L{at}LISTSERV.WEBKAHUNA.COM
    Subject: Need Help w/ Ageton method...

    Is anyone willing to help a newbee with the Ageton method?  I found a copy of Ageton's Celestial Navigation, copyrighted 1943.  I've gone through the example in the back chapter on using the method with D.R., but I don't understand where he gets the value 'R'.  I can see how he draws the line segment, but where is that value taken from the table, or is it derived from a formula only?
     
    Thanks
       
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