NavList:

Dear Frank,

Looking at http://www.rtl-sdr.com/spoofing-gps-locations-with-low-cost-tx-sdrs/ I guess your app might be needed pretty soon. :-/

As for the screws on your horizon mirror working loose, that has only partially to do with them being "factory tight". In my experience as a mechanical engineer it is to be expected screws will work loose (especially in softer metal like aluminium), if alone because of the difference in thermal expansion between the aluminium and the material the screws are made off. So when replacing parts like you did I would recommend to thoroughly yet carefully clean the threading and then assemble the parts with Loctite Blue or - Purple (http://us.henkel-adhesives-blog.com/post/All-About-Threadlockers/The-Difference-Between-Red-Blue-Green-and-Purple-Threadlockers/), or some other product with comparable characteristics.

By the way, thank you for the elaborate answer on the precalculated lunar distances. It is much appreciated.
By the way, I did find a rounding error on my side, on top of what you mentioned, between the result when calculated on a Casio FX-4500P and when calculated by means of the RealCalc Pro app for Android. The latter, with an internal 32-bit representation of numbers, yielded a comparable result to what you mentioned in your mail. The same calculation, executed in the same manner, on the Casio yielded quite a difference.

Regards,

Jaap