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Re: No Two-Body Fix Problems
From: John Karl
Date: 2009 Nov 5, 18:51 -0800
From: John Karl
Date: 2009 Nov 5, 18:51 -0800
Peter, OK, good. I should also mention that there's no need to use the other solutions to the inverse cosines in Eq. 7.5a&b (i.e., like 180-A) because those solutions just switch (A+B) and (A-B) when substituted into cos(A-B) in Eq. 7.5d (maybe this isn't obvious). But that doesn't matter since we're computing both solutions anyhow. And I agree that the equations should be perfectly well behaved in all practical cases. They only blow up at 90d declinations, 90d altitudes, or zero D12 -- cases that will never occur in practice. Also the equations will give the correct result for osculating LOPs. In that case B=0, and the two solution for (A+B) and (A-B) will give the same answer. So these equations should be straight forward to implement in computer code. John --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList+@fer3.com -~----------~----~----~----~------~----~------~--~---
