NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lewis and Clark. was: sextant practice and time keepers
From: Ken Muldrew
Date: 2010 Sep 21, 10:55 -0600
From: Ken Muldrew
Date: 2010 Sep 21, 10:55 -0600
On 21 Sep 2010 at 9:30, Antoine Couette wrote: > For the Lunar distance observations, night of 2-3 Dec, 1803, you > indicated : > > "Those confusions relate to ordinary altitude observations, but things > get > much worse when we reach the attempts at a lunar, at Kaskaskia, on the > night of 2-3 December, 1803. Try as I might, I am quite unable to unravel > the observations to make sense of them. If anyone else can arrive at any > understanding, I would be most pleased to hear about it. Details are all > there on the website, if you follow the journey to that date." > > I wish to give it a try : what observer's coordinates should I (best) use > to re-work these Lunars ? We had a go at those bizarre lunars once before on Navlist. Once you have had some fun with them, it might be amusing to see previous speculation on these incomprehensible data. http://www.fer3.com/arc/sort2.aspx?y=200404 I was convinced that they were reading off the wrong side of the nonius. If you work the aldebaran lunars with an offset of 15�15', then they work out rather well but the intervening Regulus lunar has a different offset. So unless they used two different instruments for the different stars, or two different individuals made the observations, it remains a mystery. Whatever else you get from trying to figure out these data, you will be quite convinced that the instruction that L & C received in celnav was too brief. Ken Muldrew.