Jan - Astronomy Club of Tulsa

Astronomical League Analemma Program, by Brad Young, Ct’d.
Results
The results were not as accurate as I had hoped, but they do provide some idea of what the analemma looks
like. The major error appears to be in time, with minor errors introduced by measurement of distance. This is
certainly historically predictable; accurate timekeeping is one critical reason for deriving the EoT in the first
place. The three methods had their problems as already mentioned above, but the method I’d hoped would
be most accurate (BOK) suffered from another unforeseen one – map projection. I suppose I could have
painted spots on the parking lot, but that seemed more risky than running around with a strange box!
Probably the most important lesson I was reminded of is that experiments can be messy. Even using three
methods did not negate the systemic errors that often affect empirical data. I did learn a few things about
computer time updates and using a webcam. I also gained a new respect for the ancient astronomers that
first began to measure the analemma and derive Earth’s orbital details from it.
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