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Dear Bill,

Thanks for your excellent contribution which I think had escaped my attention and which I discovered this afternoon after having extensively studied the environment of this unusual "Lichtenstein Lunar" .

I was not happy with my early results since some of the ones I earlier submitted here did not match the constrained heights for both the Moon and Procyon. Thanks to a nice friend to having drawn my attention onto this point.

First of all: I agree with your conclusions that :

Second, I had to trick my own Lunar program to fully use it in the specific configuration mentioned here-after which probably accounts for many of the irregular features of this strange Lunar.

Starting from only the published heights and approximate UT, and for your low level values :  MSL, T = 10°C and 1010 hPa, I derive a single position at N47°01.5' / E009°25.6' (at Sargans a few miles south west of Lichtenstein) and I see a UT of 03:38:52 s (vs you 03:38:54) for which FER's Lunar analyser says : Error 0.07 NM.

Starting again from only the published heights and approximate UT, for your Altitude = 450 m, T = 12°C, QFE = 961 hPA I derive a single position at N47°01.8' / E 009°17.3' (about 6 NM to the West of previous position) and I see a UT of 03h39m29s (vs your 03:39:31) . While I need entering my own program with QFE everytime, since refraction immediately depends on QFE, we are to keep entering FER's Analyser with QNH instead because it makes an automatic calculation of QFE as a function of Altitude. So we are to enter both Pressure = 29.92" and Altitude = 0.5 km if we are to get meaningful comparisons : here again 0.07 NM difference.

An alternate way of solving this Lunar can be to start directly from a position in Lichtenstein (e.g. your position at Vaduz) and by comparison of our results we see that the UT determinations stay quite "stable", which is quite surprising given the exception to the "usual" rule mentioned here-above.

Obviously, there are other more expeditious ways of solving this Lunar, as suggested fy FER in his original post.

The last thing I discovered and which may be of importance to explain the oddities of this Lunar is that - not only the Moon and Procyon Azimuths are almost identical - but interestingly enough after UT = 3h38m40s for all possible values of the Moon heights [between 40°24' and 40°34'] and Procyon [between 10°14' and 10°24'] the Moon and Procyon Circles of Position no longer intercept at all on Earth.

Would this explain that ?

Bill, as we both are retired Airline Pilots - at least I am retired now - I would like to take this opportunity to keep discussing this together, if you so desire.

Antoine M. "Kermit" Couëtte

antoine.m.couette[at]club-internet.fr