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Re: Biruni and the radius of the Earth by dip
From: John Huth
Date: 2011 Jan 4, 18:44 -0500
From: John Huth
Date: 2011 Jan 4, 18:44 -0500
Also - looking at the numbers, I'm confused. Frank points out that the bending is 90% of the dip effect - in the article you attach, the author says that refractive dip alone causes a 40 arc minute effect, based on some assumed atmospheric conditions. But the reported measurement is 34 arc minutes. So, it's not clear to me in the final statement how the author concludes that the measurement was 6/5 correct.
I need to run some numbers at this point, so I'm going to shut up and do just that.