Two On A Big Ocean The Story of the First Circumnavigation
of the Pacific Basin
in a Small Sailing Ship

      

Other Books by
Hal Roth
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longitude calcs

Subject: longitude calcs
From: mail (mail@XXX.XXX)
Date: Tue May 06 2003 - 17:28:12 EDT

Please can someone help me.
I'm sure this has been covered before so please direct me to the correct archive.
I cannot understand how to calculate a longitude from a time.
example in book:-
09h 43m 30s
x 60
-------------------
          583.5m
x 15 (=15 minutes of arc/minute of time)
----------------
          8752.5
divide 60 (minutes/degree conversion).
-------------------
     145deg 52.5min
this where I lose it. I make 8752.5 / 60 = 145.875
what is wrong please?
If I enter 145d 52.5 in to a calculator program it comes out as 9h 43m.30 so the calculation I assume is correct and I am being stupid help please Gentlemen.

Alistair Barclay
www.adwb.freeserve.co.uk



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