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    The Rude Star Finder and teaching stars
    From: Frank Reed
    Date: 2010 Nov 7, 00:07 -0700

    Byron, you wrote (in the "hiding stars" thread):
    "One of the reasons that I join the Journal of navigation, and later Navlist, among other navigation forums, was to try and keep navigation, especially celestial Navigation alive. Navlist is important to me because I think that Navlist is striving to teach, talk, write about and help keep celestial navigation alive."

    Yes, that's why most of us are here, in addition to the good, clean fun of it. :)

    Maybe in reply to a comment I made about other options besides the standard navigator's "star finder", you wrote:
    "I realize that they are many ways to easily get bearings and altitude of stars, but these are the black boxes that the answer comes from; the answer is quick and just there. There is no thought it just comes with no insight or knowledge, there is no way to understand if it is even correct, It is a great check on your work , but you are certainly not the master; the equipment is, right or wrong."

    The Rude Star Finder is a good but primitive tool for the task, and in many ways, it, too, is a black box. The original version of it was invented by Gilbert Rude (apparently pronounced "rudy," I learned today) and first manufactured sometime in the 1930s. It was standard USN equipment starting in the Second World War. It became a traditional component of "apex celestial navigation" (this is the name I use for the highly standardized, exquisitely optimized, and even ritualized form of celestial navigation that was practiced in the latter half of the 20th century, particularly after the year 1958, especially on American and British vessels). The Rude Star Finder as "H.O.2102" has been treated as part of the complete navigator's "toolbox" for decades, but is it an "essential" part of celestial navigation? Should every student of celestial navigation use it? Are there alternatives to it that are equally traditional for the art of navigation? And is the traditional Rude Star Finder better than a modern "black box" electronic solution?

    First, is the Rude Star Finder essential to celestial navigation generally? Well, obviously not. Navigators used the stars for navigation long before it was invented (though there's ample evidence that teaching the constellations was a major roadblock). One can certainly learn to find the stars without it. On the other hand, for navigators dropped down in the middle of an unfamiliar ocean at an unfamiliar time of the year, it sure was useful! It's not hard to imagine how dramatically important this was in the Pacific War in the 1940s. Imagine being assigned to a new navigation posting near the equator in the Pacific when you've never seen anything but the sky from, let's say, Chicago before. No problem -- you just dial it up on the Star Finder, and there you have them: the altitudes and azimuths for your evening round of stars including a few stars you've never seen before in your entire life.

    Second, should every student of celestial get one, study it, and employ it when taking sights? No way! Some students will find them very appealing. I've always thought they're rather "cool-looking" with their plots and overlays, and they do exercise some of the other concepts of celestial navigation. But students these days come to celestial navigation with a great variety of interests and ideas of what they're going to get out of it. There is no reason to "force-feed" the Rude Star Finder. Offer students alternatives. Every student is different.

    Third, what alternatives are there that do the same job but also help to preserve traditional navigation methods? Well, the Rude Star Finder is primarily an object of American navigational tradition. You can see an alternative on the bridge of a vessel in that Coutinho video: a star globe. Star globes are much more obvious in their function and application for most people. The calculational approach to setting one up is quite similar to the Rude Star Finder as far as LHA is concerned, and for latitude, you just rotate until the declination of the zenith equals your latitude. Such star globes were fairly popular in other navigational traditions --old Soviet star globes turn up on ebay fairly often. Naturally, star globes took up more space. The Rude Star Finder flattens the star globe. Beyond these devices, there is the simple skill of learning to use a star chart and learning the tricks of the sky like following the "arc" (of the Big Dipper's handle) "to Arcturus". The "tradition" of celestial navigation is not bound necessarily to the Rude Star Finder. Or you could borrow a planetarium (see the PS).

    Lastly, is the Rude Star Finder better than "black box" electronics? Is it better than a computer? Absolutely not. In fact, it is an analog computer. It requires certain specific algorithmic steps to set it up which are practiced generally according to certain rote rules and then its "output" is read from its "display". Most users don't find out whether they're doing it right or wrong until they get outside and find that the stars either match the predicted numbers, or, not infrequently, they're not even close. The star finder is a non-electronic "black box". And I note that the algorithms for setting the Rude Star Finder sometimes encourage as much disconnect with navigational reality as any modern computer software. For example, Gary corrected an error in Alan's calculation of LHA Aries of three minutes of arc (and both are calculating to TENTHS of a minute of arc). Needless to say, this device requires no such detailed accuracy in its setting. That's "black box" thinking right there. The altitudes and azimuths produced by the Rude Star Finder are nowhere near accurate enough for such small details. This ain't lunars! :-)

    By the way, Byron, regarding your class you wrote:
    "I recently started a class with only a few interested, I think because of the time 1 PM in the afternoon."

    Yeah, when I saw that class time (on a weekday, right?) in an earlier message, I wondered whether it might be an issue. I am in Chicago this time of year, else I might have offered to help. You may want to start talking with local boating organizations, yacht clubs, etc. and maybe local colleges. Get one of them to do the hard work of scheduling, publicizing (VERY important), collecting fees, etc. for another run of your class, and think of this current class as a practice run. In fact, the idea that you have done a practice run could be a useful "talking point" when you propose this to some other supporting institution. There's definitely a local market for this sort of thing in Newport. It's just a matter of getting the word out. Oh, and don't forget to "sell yourself" as a main attraction. Your vast personal experiences, sea stories, and your unique history will be a major draw.

    You concluded:
    "I believe by working the sight form and observing the setup on the two minutes star finder is a way to teach and create more interest while making everything easier to understand."

    Well, it might be. Just make sure it's fun, too! Sea stories help. :-)

    PS: I did a Google News Archive search an hour ago on "Rude Star Finder" and found just a handful. There was an article from the New York Times dated June 6, 1968 (I was four). It described using a planetarium to study the altitudes and azimuths of stars in preparation for the Newport-Bermuda Race. It listed a couple of dozen azimuths and altitudes of stars and planets, probably one of the few times such detailed tables have appeared in the NYTimes. From the article: "The turnouts last year, the first time we held such previews of the skies, were rather small. ... But that is understandable since most experienced navigators are able to compute their routes by chart and can use such aids as the Rude star finder. About 14 crews were represented last year at the planetarium showings, out of 150 boats in the race. Nevertheless, proper celestial navigation is important when you realize that even a one-second mistake [in time] is equal to a quarter of a mile." And who was this wise source on celestial navigation quoted by the New York Times?? None other than Donald L. Treworgy of the Seaport Planetarium (now the Treworgy Planetarium) at Mystic Seaport Museum in Mystic, Connecticut. Small world. Very small world...

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