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    Re: Star-star distances for arc error
    From: Frank Reed
    Date: 2009 Jul 2, 20:44 -0700

    Douglas, you wrote:
    "It appear to me there is a strong underlying desire by some who wish to prove 
    others 'wrong' - when someone  tramples upon little feet challenging pet 
    Let's see... when you stormed off last week, you said we were all defending 
    "sacred cows". This week, we all have "little feet" to be trampled upon and 
    "pet theories". You're digging yourself a rather deep hole, Douglas. But in 
    this group, you may just find that there are folks willing to give a helping 
    hand and get you out of there... when you're good and ready. :-)
    And Douglas, you wrote:
    "What I do not wish to do, or intend to do however,  is send one posting about 
    a subject, and then debate it endlessly,  going around in circles."
    Oh but Douglas, that is EXACTLY what you have been doing. You ignore almost 
    everything that is written in reply to you and then repeat your own 
    demonstrably false statements. Repetition does not make things true.
    And you wrote:
    "Finally, I wanted to comment on the Star distance argument by presenting real 
    objective analysis instead of the anecdotal evidence I have been presented 
    with here such as  "I regularly can obtain accuracy to 0.1 of a minute of 
    arc".   Such statements are scientifically meaningless without rigorous 
    experimental evidence and  an assessment of the errors."
    Douglas, you're making an erroneous assumption here. Just because I haven't 
    thrown lots of statistics at you, doesn't mean that I don't have them. I have 
    shot over 350 lunar distance sights in the past ten years. I've taught 
    seminars in lunar distance sights. I own a half-dozen sextants, and I have 
    mountains of data. When I say that my sights in some context have a standard 
    deviation of, e.g., 0.25 minutes of arc, do you think I just made that number 
    up? Perhaps it would help you to know more about me. There's a little article 
    that appeared in a physics magazine (published in the UK actually) that you 
    might enjoy (just for general background). It's linked here: www.fer3.com/me. 
    You might also want to review the events, topics, and speakers at the 
    "Celestial Navigation Weekends" held at Mystic Seaport Museum, one of the 
    world's premier maritime museums, in 2006 and 2008: www.fer3.com/Mystic2006 
    and www.fer3.com/Mystic2008. I personally organized these events and 
    presented a few of the "papers" presented. [please note: others will speak 
    for themselves; it's not my job. But be advised that there are plenty of very 
    intelligent folks on NavList].
    You wrote:
    "I have a report available which I have scanned from the 'Journal of 
    Navigation' (Institute of Navigation) of the mid 1960s which  has done this 
    very thing, and in detail. It is called "The Attainment of Precision in 
    Celestial Navigation" by Robert Gordon of Yale University.  The content is of 
    such importance to this whole argument ..."
    I will reply to that separately. It's "unfortunate" for you that you think 
    this little article is so important. It is a mark of considerable naivete at 
    You concluded:
    "It mentions specifically measuring star distances for checking sextants. I do 
    not think you will like the conclusions."
    As I said above, I will reply to the details of the article separately, but I 
    think I should reply to this specific statement in this post. Your statement 
    here is a mis-representation of the article's content. The author describes 
    his attempts to measure INDEX ERROR using stars. He describes his miserable 
    results which he clearly cannot explain, and then from that experience he 
    asserts (without evidence; without data; much as you have done) that 
    star-star sights for arc error wouldn't work. He has ZERO data on the topic 
    of using star-star distances for arc error. Did you understand that?? 
    Navigation List archive: www.fer3.com/arc
    To post, email NavList@fer3.com
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