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Trying to understand- was "urgent help needed"
From: George Huxtable
Date: 2003 Jul 25, 07:21 +0100
From: George Huxtable
Date: 2003 Jul 25, 07:21 +0100
Under the thread name "urgent help needed", (which seemed inappropriate, so I've changed it). Mike Burkes said- >Hi folks! An interesting observational situation occurred as follows: Using >Davis Artificial Horizon sites appeared ok i.e. graphing 2Hs vs. time on all >sites resulted in a near classic "pinwheel fix".However comparing "fix" to >map the results were off. Using my"fix" for Hc computations lunar distance >GMT differed by a mere few seconds indicating the flexibility of assumed >position choice. I feel the reason for the discrepancy stems from the >artificial horizon fluid being a combination of baby and bath oil >introducing a constant error.I did notice several aberrations while scanning >the pool. Any feedback would be greatly appreciated! Thanks! Mike Burkes I may be particularly slow, or stupid, but I understood very little about Mike's observations. What's a "pinwheel fix"? When he says comparing "fix" to map the results were off; how much off? He hasn't given us a single number to go on. What bodies was he observing sights of? From where? When? What were the resulting altitudes? What was the calculated position? What body was used with the Moon for lunar distance? What was the resulting distance? Only if we get some details to get our teeth into can we hope to respond to Mike's request for feedback. That's as I see it, anyway: it may be clearer to others, with sharper minds. I've never had much use for bath oil (or baby oil either, happy to say...). Do they mix? What was the intention behind this cocktail? If an oily substance is being chosen for an artificial horizon, it seems sensible to choose something really viscous or treacly, because wind won't ruffle its surface noticeably. Does Mike's blend of oils meet that requirement? George Huxtable. ================================================================ 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. ================================================================