Outer Planets
In 1610, Galileo turned a homemade telescope toward Jupiter and sketched four points of light that seemed to shift positions each night, and within a week he realised he was watching moons orbit another world — the first direct evidence that not everything circled Earth
On January 7, 1610, Galileo pointed a homemade 20x telescope at Jupiter and sketched four dots that rearranged themselves nightly — the first proof that worlds could orbit something other than Earth, and the observation that cracked open the Aristotelian cosmos.
