That was long, but very good. People underestimate the ancient Greeks - it's awesome to see the whole set of calculations laid out. (This reminds me guiltily of a post I keep meaning to write doing something similar for Atomism.)

Parallax effects are a surprisingly good reason to reject heliocentrism. Wrong, of course, but it does seem to fail the sniff test -- and about all the Greeks had to work with were sniff tests of varying sophistication.

Although now I kind of wonder how Aristarchus' critics explained his observations.