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: Frank Reed CT
Date: 2005 Jun 6, 22:49 EDT
From: Frank Reed CT
Date: 2005 Jun 6, 22:49 EDT
George H wrote: "It certainly does. It extends the Noon sight to a protracted series of 9 to 13 observations extending over 40 to 60 minutes around noon. Can this still be described as "a noon-sight"? " It can easily be as few as five or six sights. Whether you call it "noon anything" is up to you. But clearly this method is only a minor extension of what one does for a normal noon latitude sight. And the beginners I've explained it to seem to find no particular difficulty with this description. That is, they "see it" as a noon sight. And: "Frank's proposal, though the best way to do the job of finding longitude around noon, is quite a protracted operation. On how many lightly crewed small craft can a crew member be spared for a period of 40 to 60 minutes around noon each day while he takes such a series of shots at 5-minute intervals?" No, it is NOT a protracted operation. There is no requirement that the sights be taken every 5 minutes like clockwork. Every "five or ten" as time (and interest!) permit. As for the suggestion that someone has to give up 40 or 60 minutes of their day, gimme a break. It takes about a minute to take and record each sight. You could easily make --and eat-- lunch during that time taking a break every five or ten minutes for a quick sun sight. And: "There may be some interesting implications in what Frank is saying here. With this method, he is teaching a way of finding lat and long that is only available if the Sun happens to shine around the moment of noon. That's the position navigators were in prior to Sumner, when if they lost their noon (or near-noon) observation, both lat and long were unavailable until the next sunny noon." First, this is inaccurate historically. Sumner's discovery was considered an "exotic" sight method for decades. It was rarely used in practice. Well into the twentieth century, many vessels were navigated by traditional noon latitude and afternoon/morning time sight. But back to your main point -- yes, of course, this method is limited to those days when it is clear or partly cloudy around noon. But so what? Celestial navigation is NOT a primary method of navigation any longer. And: "So I ask; is he also teaching intercept methods to those same students? Perhaps (though I hope not), at Frank's institution, the revolution in navigation, which occurred with Sumner and Saint-Hilaire, has already been discarded." Let me clarify first that I am not formally affiliated with any "institution" at this time, and I have only informally taught the little method I've described. I have informal connections with Mystic Seaport in Mystic, Connecticut (and have been employed there on and off in the past), and I do occasional programs there. But I can tell you exactly what is taught there for celestial. There is a standard 8 to 10-week course on celestial navigation using H.O. 229 with Sue Howell's Practical Celestial Navigation as the course book (this book was written by Sue based on her direct experience with these classes in the 1970s). There is also a one-afternoon class on latitude by noon sun, which will perhaps be extended soon with the method for longitude I've described if we can hone it down to short enough instructions. Of those two classes, the noon sun afternoon fills up with eight or ten students once every four months or so. Presently, the full length class draws rarely more than two or three students once a year. Twenty-five years ago, the full length celestial class filled to capacity three or four times a year. People are still genuinely interested in celestial navigation, but since it is not a primary method of navigation today, they are much less likely to set aside the time and effort required for a full length course. Unless, of course, they are hard-core enthusiasts like most of the people on this list. And: "Does he teach how a position line can be obtained from any altitude of any celestial body, at any time, all in exactly the same way, from an assumed position?" Personally, I am willing to teach whatever the market will bear. And: "If all that has been lost (and I hope it hasn't), it would be a very crippled 19th-century navigator that would emerge from the course." Just to be clear,the method I have described for getting lat and lon by noon sun was NOT used in the 19th century. It is a modern method. Short, easy to teach, easy to learn, easy to RE-learn in one sitting, and requiring no special tables beyond four or five pages of basic almanac data which would be valid for decades. It is not a cheat. It is not "fake" celestial navigation. It does have some limitations, as do all methods of celestial navigation. As for your use of the words "crippled" and "poor" and so on, your are engaging in shameless exaggerration. And: "I ask nav-L members if they would be happy to cross on ocean, without GPS, with a "navigator" who had learned his craft in that way, and was unable to handle any other observations than those of the Sun at noon." Without GPS?? If my GPS fails, I certainly hope that someone onboard has had the common sense to bring a handheld unit. NO ONE is dependent upon celestial navigation except for their own amusement (=challenge, enthusiasm, pleasure, etc.). -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars