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    Re: Another tale from the front lines....
    From: Lu Abel
    Date: 2011 Oct 19, 09:46 -0700
    118 degrees?!   Maybe a back sight :)) laughing  ?


    From: Apache Runner <apacherunner@gmail.com>
    To: NavList@fer3.com
    Sent: Wednesday, October 19, 2011 8:36 AM
    Subject: [NavList] Another tale from the front lines....

    In the assignment due today, I asked the students to use a straw taped to a protractor and a weight at the end of a string to measure the sun's altitude at meridian passage.   

    The then had to first use a sinusoidal approximation for declination and then make a correction they were supposed to memorize and then look up the NOAA value to extract a latitude.

    I had them enter the data so I could see the altitudes on a spreadsheet - hopefully to average.   I'll ask them in two weeks to do a pair of altitudes, and show that the declination is, indeed, getting lower.

    OK, fair enough.   What about the data?   I'm reckoning 39 degrees is about right in Boston.   When I tried it with this rig, I got 40.5, but there was some wind, so I'm guessing that pushed my plumb-bob a bit, and the accuracy of a protractor and straw isn't exactly rivaling a Tamaya.    

    But...well, we got some 75 degree measurements, which worried me.   But THEN, I got two students who reported 118 degree altitudes!   Sigh.

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