Galileo turns a telescope to the sky
Moons around Jupiter prove not everything circles us
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"Sidereus Nuncius" reported Jupiter's moons, the phases of Venus, mountains on the Moon and that the Milky Way consists of countless stars — observations that together undermined the Aristotelian picture of a perfect, unchanging heaven. Galileo's methodological contribution matters just as much: quantification, controlled experiment and the mathematical description of motion. His 1633 trial has become a symbol of the conflict between science and authority, though it was also about personal politics and timing.
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Galileo built his own telescope and saw something no one had seen before: four moons orbiting Jupiter. That proved not everything in the sky goes around the Earth. The Church was displeased, and he spent the rest of his life under house arrest.
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Part of Terra Saga — the story of Earth on a timeline. terrasaga.org