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    Re: A Lunars Game
    From: Frank Reed CT
    Date: 2003 Dec 17, 01:55 EST
    Trevor, you wrote:
    "I don't have the 2004 almanac so I can't attempt to estimate
    GMT of sunset and hence longitude but I doubt that the required
    precision would call for properly clearing the lunar."

    Woops! I forgot about that. I should have included a link to that Brazilian version of the Almanac that's available online. Here ya go:


    I've now added that to the web page, too (which, if you're joining us after the commercial break, is www.clockwk.com/lungame.html ).

    You're right that the precision needed in this puzzle wouldn't require you to 'properly' clear the lunar (but a little parallax can go a long way!). Besides, after the helicopter has dumped you at your destinaton, you don't have any tables with you, you don't have a sextant, and so on, so there's no chance of a 'proper' clearing. But how close can you get in longitude from the information given? What are you error bars? And how accurate is your latitude for that matter?? This is mostly intended to be an example of estimating how much you CAN accomplish with a "naked eye" observation of the sky. It's a bit contrived, of course, but how badly so? How often in a month could you do this sort of thing? If you were really a contestant in this game, how likely is it that you could win by lunars?!

    This simple lunar problem is cake for experienced Nav-L lunarians, but can beginning Nav-L lunarians work it out?

    And if you wish to "spread the word" on lunars to those interested in navigation with very basic astronomical backgrounds, they're going to be very much beginning lunarians. The basics come first. Does this sort of example help?

    Frank E. Reed
    [X] Mystic, Connecticut
    [ ] Chicago, Illinois
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