Galileo And The Moons Of Jupiter

It is here in Galileo’s series of observations that he makes the following brilliant conclusion: ... Control click on Callisto, then choose Orbit to show the orbit. Measure the diameter of Callisto’s orbit, estimating to the nearest mm. Record this in the Table. Go backward in time a few hours to place Callisto near the edge (limb) of Jupiter and record the Julian date in the Table. Then ... ................
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