Aristotle’s Universe: Earth’s Motion
•Aristotle had good reasons to think the Earth stood still:
–Absence of any detectable parallax

If the Earth orbits the sun (rather than the reverse) then we should be able to see shifts in the positions of the stars due to parallax.
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•The amount of parallax is proportional to
–We now know the distance to the nearest star is so large that even it only has a parallax of 1 second of arc = 1/3600 deg.  1 parsec = 3.26 ly.
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From our text:  Horizons, by Seeds