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Re: Modern Lunars
From: Geoffrey Kolbe
Date: 2016 Sep 19, 07:19 +0100
From: Geoffrey Kolbe
Date: 2016 Sep 19, 07:19 +0100
On 18 September 2016 at 18:18, Antoine Couëtte <NoReply_Couette@fer3.com> wrote:
In other words, I am convinced that modern computation tools should rather use SEXTANT DISTANCES rather than CLEARED DISTANCES as benchmarks.
I agree entirely. When lunars were developed, the NA had cleared distances in it to which your own cleared distance could be compared. That is not the case any more. I think that when doing practical lunars today, it is more straightforward to compute what the observed distance should be and compare that to the 'sextant distance'.
Hence my suggestion for improving your on-line Calculator, Frank, through implementing accurate and meaningful information about the expected accuracy of the Lunars we are computing on your site.
In Frank's defence, he is a student of the 'classical' methods and his online lunar distance form is designed to confirm the computations of someone who has used a classical method to clear a lunar distance - I think. (I have to confess, I have always been somewhat confused by Frank's lunar distance clearing form.)
I would also question what might be called an obsessional trait in computing a lunar distance to the nearest arc-second or better, taking into account all the corrections you can think of. Given that 0.1 MOA is a practical limit of observations using a sextant, why strive to compute a lunar distance to greater accuracy than that?
Geoffrey Kolbe
