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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Revisting refraction
From: Frank Reed CT
Date: 2005 May 14, 23:19 EDT
From: Frank Reed CT
Date: 2005 May 14, 23:19 EDT
Bill you wrote: "I noticed the 2005 Nautical Almanac provides a refraction formula similar to the one Paul posted in its sight reduction/direct computation section (page 280): Ro = 0.0167 / tan (H + 7.32 / (H + 4.32))" I couldn't locate the reference, but somebody sent a message to this list within the past six months (??) pointing out that the refraction table on the inside of the front cover of the Nautical Almanac was slightly changed for 2005. It may even have been you (??). Since they changed the table, the formula would have to be changed to match, and I think that's all you're seeing here. As George H has already pointed out, this change has little practical importance (even for lunars!). I have a feeling the gang at the almanac office is getting a little bored... -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars
