NavList:

Hello to all,

In reply to a few recent posts related to this Magnificent Pic du Canigou Sunset (https://canigou.allauch.free.fr/Refract_atm.htm), you will find in the attachment the Augmented Refraction Tables [-1°, 0°] built upon solely the Éphémérides Nautiques and the Nautical Almanac after I had derived a very simple formula as the backbone of both such Augmented Tables.

We are in some unusual situation here because  - even in Standard Atmosphere - there is already some scatter / dispersion between the published results of both these authoritative sources. For this reason a Dispersion/Scatter rightmost column has been added to remind the Navigators about the great variability of the Astronomical refraction just above and also just under the Astronomical Horizon.

Last but not least, many moons ago, I once read somewhere that some similar tables had been in use on-board SEASHIPS at least in the French Navy in the XXth Century. It certainly would be quite interesting to compare them with the current Augmented Tables. Anybody aware of such SEASHIPS / SEAPLANES Very Low Altitude Astronomical Refraction Tables ? Anybody knowledgeable about this historical topic ? 

Meanwhile, do not hesitate to contact me accordingly,

Kermit

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