NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Douglas Denny
Date: 2010 Mar 11, 03:25 -0800
George: Bill Morris posed this question:-
"Gentlemen
When I posed my initial question, I was looking for a general case solution. In my usual obtuse fashion, it came across as a special case question, and at that, poorly stated.
A search through the archives provided this clearing method. http://fer3.com/arc/m2.aspx?i=015102&y=200404 Would this still be considered a good general case solution? "
-------------
George,
You queried my previous postings.
Are you now satisfied with my general case solution for the two star distance problem with included Zenith/Rational Horizon diagram? It should be a rigorous solution unless there are flaws I have not noticed.
I do not incidentally, understand your method which mentions an addition of refraction. Refraction should be subtracted every time.
--------
In my method there are three spherical triangles to calculate.
I have not included the trivial spherical formulae for the spherical geometry but will do so if you want. For calculation of Azimuth one can use spherical Cosine formula, or Four-Part Formula. Cosine formula for the second triangle: star1/star2/Azimuth difference for included angle.
The rational horizon diagram is not perfect and can be improved. I might do so later and re-send it. The lines through the stars to the horizon should be straight. The azimuth angles should have been indicated not the bearing angles (which I am used to with Marc St Hillaire all the time so that's how I drew it without thinking).
Douglas Denny.
Chichester. England.
----------------------------------------------------------------
NavList message boards and member settings: www.fer3.com/NavList
Members may optionally receive posts by email.
To cancel email delivery, send a message to NoMail[at]fer3.com
----------------------------------------------------------------