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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Moonrise-over-Connecticut
From: Paul Hirose
Date: 2021 Nov 7, 23:11 -0800
From: Paul Hirose
Date: 2021 Nov 7, 23:11 -0800
On 2021-11-07 21:00, I wrote: > On 2021-11-05 14:30, Peter Blaskett wrote: >> Celestial Navigation Data for 2021 Nov 6 at 11 43 35 UT (GMT) >> Delta T = 87.7 seconds >> For Assumed Location: Longitude 0 00.0 >> Latitude 0 00.0 > > At that time and place, with the ICE delta T, the Lunar 4.4 program gives: > > Moon geocentric apparent place > 244°53.26' -21°54.44' equinox RA, dec > 135°43.80' +58°35.81' geocentric az, el > > However, the correct delta T is 32.184 (a fixed value) + 37 (until the > next leap second) - -0.107 (UT1-UTC from IERS Bulletin A). The sum is > 69.29 s. With the correct delta T: > > 244°53.06' -21°54.39' equinox RA, dec > 135°43.97' +58°35.99' geocentric az, el > > ICE altitude error is almost 0.2'. Correction: 0.2' is the altitude error of my Lunar software if I force it to use the ICE delta T, vs. its output with the actual delta T on that date (second set of coordinates). I don't have ICE but would be interested to hear what it says. -- Paul Hirose http://sofajpl.com/
