NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Modris Fersters
Date: 2025 Dec 28, 08:02 -0800
Dear Antoine,
Thanks for your detailed lunar story. I really enjoyed reading it.
I see that Paul already published his results in NavList. But they are calculated from your given approximate position (solving for time). Therefore I will add some results from Paul's Lunar4.4 using your exact position 46° 41.2'N; 2°19,9W, because you published your results using this location.
1) 15.12.2025. Geocentric distance:
- Lunar4.4: 33°21,97'
- Antoine's program: 33°22,0'
Difference: 0,03'
2) 15.12.2025. Topocentric near limb apparent distance:
-Lunar 4.4: 32°33,26'
-Antoine's program: 32°33,18'
Difference: 0,08'
3) 16.12.2025. Geocentric distance:
- Lunar4.4: 23°9,41'
- Antoine's program: 23°9,4'
Difference: 0,01'
4) 16.12.2025. Topocentric near limb apparent distance:
-Lunar 4.4: 22°23,65'
-Antoine's program: 22°23,57'
Difference: 0,08'
5) Refraction for Mercury:
-15.12.2025.: 13,81'
-16.12.2025.: 14,17'
As you can see the differencies in results between Lunar4.4 and your calculations are smaller than 0,1'. I would say: perfect match under these extreme low Mercury altitudes conditions.
PS. Effect of center of light for Mercury is taken into consideration.
Modris F






