NavList:

RE #1 : https://NavList.net/m2.aspx/Longitude-calculator-theodolite-FrankReed-jun-2013-g24468
RE #2 : https://NavList.net/m2.aspx/Longitude-calculator-theodolite-Couëtte-jun-2013-g24466
RE #3 : https://NavList.net/m2.aspx/Longitude-calculator-theodolite-Pennino-jun-2013-g24454

Hello Frank and Bruce, and Hello to all,

To you first Frank, Many Thanks for challenging in (RE #1) my last results published in (RE #2).

Oooops ! I actually performed my calculations with a position being N42°20'30" W071°48'50" vs. the true value which is : N42°20.3' W071°48.5'

Hence my updated corrected results :

UT = 00h27m02.0s Height = 30°06.267' i=-0.17 NM Z = 163.6°

UT = 00h28m36.0s Height = 30°11.150' i=+0.22 NM Z = 164.0°

UT = 00h30m23.0s Height = 30°16.100' i=+0.21 NM Z = 164.5°

UT = 00h31m35.0s Height = 30°19.500' i=+0.36 NM Z = 164.8°

UT = 00h32m26.0s Height = 30°21.550' i=+0.15 NM Z = 165.0°

The Intercepts hereabove are now extremely close from yours once your suggested +0.15' Oblateness Height Correction has been added to your own results. See as follows :

-0.35 + 0.15 = -0.20, +0.1 + 0.15 = 0.25, +0.15 + 0.15 = 0.30 , +0.15 + 0.15 = +0.30 ,0.0 + 0.15 = 0.15 where we now observe that our greatest difference has narrowed from 0'45 down to 0.09' (at least a 5 time improvement over our extreme differences with an updated averaged difference of 0.026' - i.e. only 1.6" - on our five intercepts).

Yes, I have long observed that the USNO online calculator does NOT fully include the oblateness. (See " https://NavList.net/m2.aspx/Nitpicking-Moon-Height-Corrections-Couëtte-may-2013-g24183 ").

So anyway, we are back on the same spot .... :-) .... and thanks again for straightening me up.

And last but not least, I fully agree to your remarks on the "position dilution" occurring when attempting to derive Longitude once the chosen LOP's become to be parallel to the Earth Parallels ... And whatever the Formula chosen, it is NOT a Formula problem here, but simply a geometrical situation Factor. Anyway, it is still interesting to observe the significantly increasing quantity "Δ Long. /Intercept" as the Moon comes closer to the South (see my enclosed Document). Math somewhat indicate and also confirm this point.

For you Bruce, since you seem so annoyed at your computational results, (RE #3) , I have redone extensively all these computations and I enclosing them in the enclosed document(s) submitted to your best judgement and analysis. I have published them with sooooooooo many digits which obviously far exceed the actual accuracy achieved or achievable, but at least you can have a good feeling of their variations over the course of these observations. Hopefully no typos ... and be nice and indulgent if so. I still hope that these data should be accurate certainly to the nearest 4". Any independent confirmation of these results from third parties (Paul, Dave, other ???)

And to you Bruce it is extremely nice to confirm that the quality of your observations is starting to be quite good (averaged intercepts close to 9"). May I still suggest that you might also publish your actual environmental data (i.e. Temperature and Pression) at your Position because their accumulated effects start being important and quite significant. I simply used best guess values for these parameters for lack of more accurate data here.

Hope all this helps,

Best Friendly Regards to both of you Frank and Bruce,

Kermit

Antoine M. "Kermit" Couëtte
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