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Re: Re: David Thompson's Navigational Technique
From: Mike Burkes
Date: 2004 May 31, 16:49 -0700
From: Mike Burkes
Date: 2004 May 31, 16:49 -0700
Hi Bruce, I was conferring with George off list regarding NA data
especially online vs original Almanac data and discrepancies occurred. For
example your Oct 11 and 12 dates differ from online NA data! I just
thought I would mention that.
Mike Burkes
----- Original Message -----From: Bruce StarkSent: Monday, May 31, 2004 12:03 PMSubject: Re: Re: David Thompson's Navigational TechniqueThe plot thickens.
I was reading George's post again, and didn't skim over the part where he says "Wouldn't an angle of 24" in lunar-distance convert to 48" (not 12") in time, which would convert to 12 minutes (not 3 minutes) of longitude?" That's been cleared up now. But since he was right, I wanted to work the observations and try to figure out what was going on.
Just as Thompson may have done, I turned to a 1796 edition of Moore for the sun's declination. But after taking the declination out (of Table XVII for the years 1792, 1796, 1800, and 1804) I noticed some small print in the table heading: "Each being Leap-Year." An alarm went off.
The point is, 1800 was not a leap year. It isn't divisible by 400. Wasn't this the cause a big foofaraw, and a humiliation for Moore? For Oct. 11th the declination is given as 7° 24' south. For Oct. 12th, 7° 47' south. Is that correct?
Bruce
