Next message: Jared Sherman: "Re: Checking a sextant calibration."
Paul Hirose wrote:
>
> Just pretend I'm from Missouri and show me your method with a fully
> worked example.
Answering my own challenge, here's a fully worked example of one
simple way to check a sextant's calibration.
Position 40 41.4' N 074 02.7' W (accurately determined by GPS or other
means)
Time 2003-10-07 14:12:53 UT
Sun Ho 32 17.6'
Submit the position and time into this USNO Web page:
http://aa.usno.navy.mil/data/docs/celnavtable.html
It says the Sun's Hc = 32 16.9', so our Ho was .7 minutes greater than
expected. But remember, that discrepancy isn't just instrumental
error. It includes errors in the applied refraction and dip, and
personal error. Based on that one data point, I'd say there doesn't
seem to be anything seriously wrong.
