NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Latitude and Longitude by "Noon Sun"
From: Robert Eno
Date: 2005 Jun 7, 12:57 -0400
From: Robert Eno
Date: 2005 Jun 7, 12:57 -0400
In response to Frank's note: > The advantage of this Lat/Lon by Noon Sun business is that it's very easy > to > teach, learn, and re-learn, and requires an absolute minimum of equipment > and books. A navigation student who has been away from practice in > navigation > for ten years may not remember how those tables work anymore, but you can > pick > up Lat/Lon by Noon Sun in a few hours and have a decent celestial fix at > the > very next noon. No arguement from me on this Frank. I quite enjoy the noon sun shot for its instant gratification. And I am not questioning its utility. > Tell me then, if it is so easy, why doesn't everybody do it?? I'm not > kidding. I have observed many students learning celestial and they tend > to come > from wide-ranging educational backgrounds and skill sets. For many > people, it's > all just damn confusing. I helped out a couple of years with a class in > which > one of the students was a skilled, highly-paid surgeon. And he couldn't > make > heads or tails of celestial navigation. His wife, however, loved it and > understood everything. I have experienced the same thing. I "trained" (if you want to call it that) two north pole expeditioners on a simple method for maintaining a heading using the sun as a guide at various times of the day. I printed off a little table -- based on data from the Nautical Almanac -- for them to use so it would be easy. In this case, it was the reverse: the husband grasped the concepts immediately, while his wife simply couldn't connect. The mathematics behind celestial is not something that everyone can easily grasp. Why this is, I don't know because I've always been of the mind that if I can understand it, anyone can. I am not particularly brilliant in the field of mathematics. But then again, motivation has always been a strong factor for me to learn new things. > Where is this world where one crosses oceans without GPS? Are you > concerned > that yours might break down? The best backup for GPS is another GPS. I have to disagree with you on that point Frank. The ocean is a hostile environment and in a hostile environment, the first thing to disintegrate/fail, if things go wrong, is usually the electronics. I am reminded of the preface to the second edition of the Sextant Handbook in which Bruce Bauer writes: "...Off the Atlantic coast recently our radar, loran, and single sideband radio all were smoked in one brilliant instant by a lightening stroke merely near our vessel -- not even a hit." But getting away from the hostile environment arguement, GPS is a single system and no matter how many receivers you have, if something goes wrong with the main system, you're hooped. In today's unsettled and violent world who is to say that DoD may not either shut the system down without warning or simply degrade the signals to the extent that they would be no more accurate than what you can obtain with a sextant? > Celestial navigation is no longer a primary method of navigation. Sadly, this is true. There > are plenty of > people who want to do it for fun and challenge and maybe, just maybe, for > a > backup in case something happens to the main GPS *and* the various spare > GPS > receivers. There are others who do it for various certfications. But why > else? Backup and the satisfaction of being something other than a mindless push-button navigator. Wait, wait... I've got it! You're at war with another maritime > power. You > are engaged in a naval battle and the other vessel surrenders. You send an > officer aboard to take your prize into port and discover that the enemy > crew > have thrown overboard the ship's GPS receivers! How will you ever get your > prize > back to port. Sure, you can borrow one of the three spare GPS receivers > from > your own vessel, but what happens when you have captured two or three > other > enemy vessels?? That is when you will need your sextant and celestial > navigation! (in case you don't recognize this, it is a rewording of a > excuse for > studying 'longitude by lunars' from the late 19th century which I posted > to the > list a while back). Actually, why not just tow them all back ;-^) > And concluded: > "I won't delve into the "what ifs" (what if my watch went overboard > etc.)." > > If you're willing to entertain the highly unlikely possibility that you > might cross an ocean without GPS, then dropping your watch overboard > seems like a > sure thing!Actually, in 1986 while I was the navigator in a crew running a small boat up the west coast of Hudson Bay, I did, in fact, lose my watch overboard. Fortunately, we were close enough to the coast that a sextant was not required and in any case, we didn't have one. All the best Robert