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  -Made the 1st good measurement of Earth's size (circumference)
 -Discovery made: 240 BC
 -Significance: He knew the Earth was round, but this proved and solidified his claim.
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  -Discovered evection/lunar theory- irregularity in the moon's motion
 -Discovery made: Sometime between 127-141 AD
 -Significance: Explains that the moon goes all the way around the Earth in the same time it takes to spin around just once
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  -Came up with the Heliocentric System (The idea that planets orbit around the sun)
 -Discovery made: 1543
 -Significance: It is an important concept (that is true) that says the sun is the center of everything. (All planets orbit around it).
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  -Discovered the new star Cassiopeia and made publications of it
 -Discovery made: 1572
 -Significance: The publications were accurate, and showed that this new star is farther away from the moon, and is among the fixed stars.
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  -Created the 3 Laws of Planetary Motion "(1) the planets move in elliptical orbits with the Sun at one focus; (2) the “area law” (3) the harmonic law.” -Britannica.com
 -Discovery made in the early 1600s
 -Showed a precise distance between the planets and the sun, and the time it takes for planets to revolve around the sun
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  -Invented Calculus
 -Discovery made: Between 1664-1669
 -Significance: His invention led to the forming of laws of gravity and motion.
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  -Created E=mc2
 -Discovery made: 1903
 -Significance: His discovery helped expand Newton's theories later on