•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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