NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sumner's Line (Navigation question)
From: Bill B
Date: 2006 Feb 7, 17:10 -0500
From: Bill B
Date: 2006 Feb 7, 17:10 -0500
> This subject was rather thoroughly discussed on this > list in September 2004. I suggest you go to the > archives at Thanks Chuck The posts augmented Frank's excellent explanation, an confirmed my suspicion that one could also determine longitude by adding or subtracting LHA to/from the body's GHA at the time of the sight. Bill