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Greek astronomer Claudius Ptolemy proposed the first solar system model known as the geocentric theory. Which features the earth in the middle of the solar system.
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Period: 1473 to 1543
The geocentric was disproved although it lasted a long time by Nicolaus Copernicus. It was replaced with a new theory known as the heliocentric theory which features the Sun in the middle of the solar system.
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Period: 1531 to
Edmund Halley discovered comets that orbits the earth he reasoned that the 4 comets came back every 76 years.
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Period: 1564 to
Galileo Galilei mad significantly improved the solar system model to the telescope and discovered the earth could not be orbited.
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Johannes Kepler found out that Mars and Venus appeared at different times which meant it was impossible for it to orbit in circles.
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Isaac Newton created a model most similar to Keplers but proved why the planets orbiting are called ellipses and why the revolutions have changed.
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William Herschel discovered Uranus while surveying the stars with a telescope. He also discovered the two moons of Uranus.
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French astronomer Leo Verrier discovered neptune
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Clyde Tombaugh discovered Pluto the first object found in Kuiper Belt.
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Voyager 1 and 2 are launched by NASA to study the outer solar system.