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Re: Lewis and Clark lunars - I think you've got it.
From: Bill Noyce
Date: 2004 Apr 23, 13:51 -0400
From: Bill Noyce
Date: 2004 Apr 23, 13:51 -0400
> Not quite! I originally cleared the distances based on L&C's actual > data (i.e. using 60.* degrees) and then subtracted 15? from the error > to get a perfect fit. If I subtract 15? from the original distances > and then clear, I'm left with an error of about 15'. When instead I > first subtract an error of 15? 15' (more on this in a minute), then > I get near perfect results. I agree with George Huxtable that an error in observation of 15 degrees and 15 minutes is much more likely than 15 degrees exactly. Such an error can easily arise from confusion over which end of the vernier to use as the index on the main arc. > The big problem I still have is the Regulus measurement in the middle. > I can't see them reading from one side of the nonius at one series, > switching to the other side for the next series, and then switching back. Is there any chance they used a different instrument for Regulus? > Morning coffee recapitulate phylogeny :-) -- Bill