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Re: Refraction
From: George Huxtable
Date: 2008 Jul 5, 00:03 +0100
From: George Huxtable
Date: 2008 Jul 5, 00:03 +0100
About the refraction predictions in which the Nautical Almanac tables are based, I wrote- "Indeed, the Hohenkerk / Sinclair predictions are based on a rather simple model of the atmosphere, in which the air temperature falls by 6.5�C from sea level to 11km up (that is, by 71.5�C), and then stays constant at that value right up to the limit of the atmosphere, taken to be 80 km. " And in that, I missed some vital words. I should have read- "Indeed, the Hohenkerk / Sinclair predictions are based on a rather simple model of the atmosphere, in which the air temperature falls by 6.5�C per kilometre from sea level to 11km up (that is, by 71.5�C), and then stays constant at that value right up to the limit of the atmosphere, taken to be 80 km. " Sorry. George. contact George Huxtable at george@huxtable.u-net.com or at +44 1865 820222 (from UK, 01865 820222) or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---