NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Alhena Lunar exercise
From: Antoine Cou�tte
Date: 2009 Sep 20, 13:50 -0700
From: Antoine Cou�tte
Date: 2009 Sep 20, 13:50 -0700
Sep, 20 2009 For a better understanding of the lines hereunder, refer to NAVLIST 9816 Dear Jeremy, This one will the very last one for to-day. I have used your average values both for UT = 07h43m27.8s and for Sextant Height corrected for Index error = 45�13'4 Assuming that the listed position N1535.5W04914.6 is valid for 07h43m27.8s, then observed sextant altitudes (corrected for sextant error) at this same time are 48�28'019 for Alhena and 80�45'412 for Moon Lower Limb. (1) Computing the Lunar with the forced following values : 07h43m27.8s/45�13'4 gives us a sextant distance corrected for ALL effects equal to 45�13'219. Compared to your mean value of 45�13'3, your observation error is 0'18 : EXCELLENT !!!! (2) On the other hand, if we assume that both Position and Distance have no error, then UT error would be 00m35.2s with a UT of Sextant Distance equal to 7h42m52s6, at which time the geocentric Centers distance would be 45�26'097. (3a) If we assume that both Distances and Heights are correct, then UT error is 00m19.4s . Then in such case, UT of Sextant Distance is 07h43m08.4s, Geocentric Centers distance is 45�25'953, and observed position would be N15035.6W04909.7 Good Night !!! Antoine Antoine M. "Kermit" Couette PS : Hopefully no typos ... I am starting to get tired ! --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
