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Calculating almanac predictions. (was Global oceanic tides)
From: George Huxtable
Date: 2003 Aug 26, 08:05 +0100
From: George Huxtable
Date: 2003 Aug 26, 08:05 +0100
I've received the replies from Geoff Butt to two recent questioners, before the questions themselves have turned up here. This happens sometimes. I've renamed this divergent thread. Geoff wrote (and Bill Noyce has recently commented) about his calculation of NA data-- >I can get some pretty >reasonable agreement with the NA. There are however some minor discrepancies >of the magnitude of 0.2seconds in GHA for some bodies which I don't quite >understand at the moment. There's something funny about this. NA data are provided to within 0.1 minutes only, so errors of 0.2 seconds in GHA would be invisible. Did Geoff intend to say 0.2 minutes instead of 0.2 seconds? That would also fit in better with the way the Meeus data truncates. George. ================================================================ contact George Huxtable by email at george@huxtable.u-net.com, by phone at 01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. ================================================================