NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: One-body fix
From: John Karl
Date: 2009 Apr 27, 14:59 -0700
From: John Karl
Date: 2009 Apr 27, 14:59 -0700
> I hereby display the solutions to this "one-body fix" problem, if only as a curiosity. �I expect that these have been worked out before but I haven't found them anywhere so far (references would be much appreciated). �The known quantities are the GP (Dec, GHA), observed altitude (Ho), and azimuth to GP (Zn). �From the navigation triangle we can calculate the LHA and then the Latitude: > > sin LHA = sin Zn * cos Ho / cos Dec > > sin Latitude = ( sin Ho * sin Dec �- �cos Ho * cos Dec * cos LHA * cos Zn ) �/ �( 1 �- �cos Ho * cos Dec * sin LHA * sin Zn ) > > Peter Hakel I don't know of a reference for Peter's second equation above. But, I easily calculated a different one from the standard altitude and azimuth equations: Sin L = (cosA cosH sinH - sind cosd cosLHA)/(sind cosA cosH - cosd sinH cosLHA). Since both this and Peter's check out for the special case at LAN, they're probably both OK. --JK --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---