
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Another tale from the front lines....
From: Lu Abel
Date: 2011 Oct 19, 09:46 -0700
From: Lu Abel
Date: 2011 Oct 19, 09:46 -0700
118 degrees?! Maybe a back sight
?

Lu
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.