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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lewis and Clark lunars: more 1803 Almanac data
From: Kieran Kelly
Date: 2004 Apr 21, 19:26 +1000
From: Kieran Kelly
Date: 2004 Apr 21, 19:26 +1000
Frank Reed wrote: " Remember, Lewis and Clark were NOT professional explorers. They did not have experience in navigational methods, and they may well have known nothing about the constellations before that brief period of training by Ellicott." This is very true and pulled me up when I thought about my previous comparison of Lewis and Clark to Delambre, Mason/Dixon, Gregory et al. To compare a soldier - Lewis- and a soldier's celestial navigation results to those of professional surveyors is unfair to Lewis. He couldn't have got comparable results after the brief training he received from Andrew Ellicott. Henceforth I shall cease and desist from any criticisms of the Captains' capabilities. I would however ask our American colleagues why Jefferson did not send a trained expert like Ellicott out on the expedition. If Jefferson's intent was to map the West this would have seemed a logical thing to do, particularly as he had the earlier exemplary work of M & D as a guide. Also following my earlier mention of some of the stars used by surveyors I looked up the information on two used by Gregory: Zeta Aquila is the star Deneb el Okab with a mag of 2.99. part way between Altair and Vega. Compare this mag with Alpha Aquila (Altair) of .77 and you get an idea of how faint it is. Epsilon Pegasus - the star Enif - is only marginally better at mag 2.38. I went outside last night and actually located Zeta Aquila, but only just. I sure would hate to be navigating around in the bush trying to get his star in the sextant. These old boys sure knew their biscuits. Finally Frank chided me for calling a comparison between terrestrial and marine navigators "dangerous". Quite right and I stand corrected. It was a momentary lapse into the Australian weakness for hyperbole. Kieran Kelly Sydney Australia