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    Re: Where in the world?.
    From: Paul Bedel
    Date: 2018 Aug 21, 13:45 -0700

    A first calculation with observations of Altair and Arcturus give a value of latitude wich is Lat = 8° 28,9' S. Then it's possible to calculate the local hour angle which is 303° 52,1' for Altair and 27° 40,2' for Arcturus; longitude is then Long = 14° 19,5' W.

    With those elements, it is possible to calculate the elements of the five Sumner's lines:

    Moon: intercept, +0,4', Z= 252,8°. Altair: intercept, 0,0', Z = 074°. Antarès: intercept, +0,7', Z = 163,6°. Arcturus: intercept, 0,0',  Z = 315,5°. R. Kent: intercept +1,5', Z = 192,6°.

    Without other calculations and just a graphical construction, it seems that the fix, with the 5 Sumner's line is in Lat = 8° 30' S Long = 14° 20' W (rounded to 1').

    Ascension islandis not very far.


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