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Guus Dekker....math to calculate LMT of events
From: Doug Royer
Date: 2004 Aug 18, 10:59 -0700
From: Doug Royer
Date: 2004 Aug 18, 10:59 -0700
Guus, Here are some formuli to calculate the LMT of astrological twilight,nautical twilight,civil twilight,sunrise and sunset as an alternate to the N.A. or as a check to other methods. Any scientific calculator will allow you to accomplish this quickly.Especially if you have a programmable calculator. You will need your latitude and the Sun's declination. LMT of event = ( ( 180* + or - t )/ 15 ) + t at s.r. - t at s.s. t = cos -1( ( sin - X - ( sinL x sind ) / ( cosL x cosd ) ) X at A. Twi. = 18 X at N. Twi. = 12 X at C. Twi. = 6 X at sr or ss = 0.84 You may then convert the events LMT to ZT following that procedure. Hope this helps.
