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Re: Beginner Meridian Passage Question
From: Zorbec Legras
Date: 2004 Sep 3, 11:31 -0500
From: Zorbec Legras
Date: 2004 Sep 3, 11:31 -0500
----- Original Message ----- From: "Noyce, Bill"Date: Fri, 3 Sep 2004 09:13:03 -0400 To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM Subject: Re: Beginner Meridian Passage Question > > > b) when you think Polaris is directly below or above the pole, add > or > > > subtract its difference (which you have memorized as about 45'); ============================ Latitude by pole star. Lat = true altitude + corr 1 + corr 2. Corr 1 = Pd * Cos LHA Corr 2 = ((sqr Pd)/2.3438) * sqr sin LHA * tan true altitude. Pd = pole distance = 90 - dec. ============================ Latitude by meridional transit. Upper transit: Lat = Zd + dec (1) Zd = zenithal distance (= 90? - true altitude). + Zd if elevated pole in your back - Zd if your are facing elevated pole. + dec if same name as latitude - dec is diff name. Lower transit Lat = 180? - (Zd + dec) ============================== Ex meridian (if you miss the transit) Vers meridional Zd = vers (90? - true altitude) - (vers LHA * cos assumed Lat * cos dec) with the meridional Zd use formula (1) to compute the Latitude. Vers x = versine x = sinus verse x = 1 - cos x ============================== About the elevated pole, have a dry gin and read it again... The elevated pole is the pole in the same hemisphere as the zenith. ============================== It's hard to be a hero on this planet, one to beam up... -- ___________________________________________________________ Sign-up for Ads Free at Mail.com http://promo.mail.com/adsfreejump.htm