My thanks go Werner for his detailed and helpful response to my
question, and Fabio for his interesting comments on the astrolabe.
I learned some new things today, and it was nice to see a diagram of the
offset circles on the back of the astrolabe. Clever.
Cheers,
Steve
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Dear Steven,
The relation of solar declination delta(t) to ecliptic longitude lambda(t)
delta(t) = ArcSin[Sin[23.44]*Sin[lambda[t]]
You are interested in the relation of solar declination to time since the
equinox.
Your formula delta(t) = 23.44*Sin(t), with t being the time (in degrees) since
