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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Refraction
From: Frank Reed CT
Date: 2005 Aug 16, 16:09 EDT
From: Frank Reed CT
Date: 2005 Aug 16, 16:09 EDT
Marcel wrote: " The only thing I did was feeding those data in a program published by Sky & Telescope in 1989 which calculates the refraction by numeric integration. Unfortunately I do not have a copy of the article describing the program." Just for reference for everyone else, this code is available on S&T's web site: http://skyandtelescope.com/resources/software/ as refr1.bas on page 3 of "Basic Programs". This is very old-fashioned code --line-oriented BASIC with variable names limited to two characters-- but it's not too painful to convert to your favorite flavor of a modern language, and the general approach appears to be reasonable. Bear in mind that certain choices for things like step size in integration were chosen with 1989's least expensive second-hand personal computers in mind (think Apple IIe). There's lots of other code in the S&T archive that might be interesting to the calculating members of Navigation-L. -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars
