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Re: Sunset sight?
From: Pierre Boucher
Date: 1998 Oct 29, 01:57 EST
From: Pierre Boucher
Date: 1998 Oct 29, 01:57 EST
At 17:07 28/10/98 -0800, you wrote: >Would it be possible to find position (or at least longitutde), without a >sextant by marking the time at sunset and going to the tables with 0 degrees as >the altitude? First you would not get longitude unless the Sun sets due West wich happend only twice a year at equinoxes. In the Northern Hemisphere the sun's azimut as it sets will be around 300d (at lat. 40d N) on the first day of summer and decreasing bit by bit till the equinox day. After that day it will keep on decreasing til it reach more or less 240d. As an emergency solution (life raft and sitting flat on the bottom) we teach to use -0d53' as the observed altitude exactly at the moment that the UL of the Sun touches the horizon. One thing to remember is that if the calculated altitude ended to be also negative, that -0d35' is greater then -0d53'. Pierre Boucher N ************************************************************************** X XX X Pierre Boucher N XXX XX formation en navigation de plaisance XXXX XXX Ste-Therese (Quebec) Canada XXXXX XXX XXXXXX XXX la "VOILE"... le reste n'est que du vent... XXXXXXXXXXXXXX ''Sail, Sail !''... the rest is only wind XXXXXXXXXXXX XXXX EMAIL: pboucher@XXX.XXX XXX http://www.lavoile.com ************************************************************************** =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= =-= TO UNSUBSCRIBE, send this message to majordomo@XXX.XXX: =-= =-= navigation =-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=