NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: from a watcher
From: Bill Murdoch
Date: 2002 Oct 18, 22:10 EDT
From: Bill Murdoch
Date: 2002 Oct 18, 22:10 EDT
In a message dated 10/18/02 12:27:06 AM Eastern Daylight Time, danallen46@ATTBI.COM writes:
Chapter 1 section 5 derives the cosine formula from simple plane trig. I have used it in USPS JN courses to answer the question, "Where did that formula come from?" It is not too hard to pick your way through.
Bill Murdoch
The first chapter
of W. M. Smart's classic "Textbook on Spherical Astronomy" is all
about this formula and how it is derived and used. If you understand
this formula and how to use it, you can do much of sight reduction
in your sleep. It is not a difficult formula and it is worthy of
everyone's study.
Chapter 1 section 5 derives the cosine formula from simple plane trig. I have used it in USPS JN courses to answer the question, "Where did that formula come from?" It is not too hard to pick your way through.
Bill Murdoch