NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Antoine Couëtte
Date: 2012 Apr 1, 22:29 -0700
Alex,
> What I would consider a useful improvement is adding more stars.
I totally agree with you on this point. It is possible that Frank might have developed an improved version with (many) more stars. But I do not recall having read anything about this. Frank, are you here ?
Another improvement could also be to adapt this Lunars Calculator to also deal with Occultations by the Moon (simply enter Distance = 0). This would definitely require adding many (many) more stars. While this Lunars calculator is NOT advertised for Occultations, I have checked it for some Occultations a few years back. I found that its results accuracy then was in the +/- 0.2' range, which is slightly degraded when compared to "True Lunars". As earlier indicated, for "True Lunars" (let's say with Body to Limb Distances greater than 15°/20°, a value Frank will further correct if necessary) I have observed that its overall accuracy always lies within +/- 0.07' in the 1750 - 2050 time span. One thing of importance though : Occultations - even dealing with an ideally spherical Moon - are subject to (sometimes highly) non-linear effects which can mislead "standard" Lunars Algorithms otherwise extremely efficient to tackle Lunars. And also there exist to-day some excellent Software dedicated to Occultations and/or Eclipses.
> At least my study of the accuracy of Cook's and some XIX century observations gave meaningful results with Frank's calculator.
Do you have the reference (if any) to some of your earlier posts in which you commented Cook's Results Accuracy. This I have done too for some of them, also using Google Earth to check actual coordinates.
Best Regards
Kermit
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