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Bob,

You should be good to a minute of Latitude using out of date almanacs within five years of the historic Polaris ploblem. Something for you to try is the attached radar plotting sheet graph for 1998 Polaris corrections. Use a straight edge from the center out to the LHA of Aries then span dividers from the red base line to the red circle intersection point. Measure on highlighted yellow scale to get correction.

Greg Rudzinski

Reusability of Polaris Tables
From: Bob Goethe
Date: 2015 Sep 7, 07:30 -0700

I am trying to work out a historical problem utilizing the Polaris-table data from 1998.

I understand that if I have a Nautical Almanac for a given year, that the sun's GHA/Dec numbers will be reusable four years later.  That is, if I have an almanac for year 2011, the sun's data should work pretty well for year 2015.

Question #1:  Is this also true of the Polaris tables?

Question #2:  If the answer to question #1 is "no" then does anybody have a scan of the Polaris tables that they can post from 1998 specifically? 

Question #3:  If the answer to question #1 is "yes" then does anybody have a scan of the Polaris tables that they can post from any one of the years 1994/1998/2002/2006/2010/2014?

Thanks,

Bob Goethe

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