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Astronomers
Claudius
Ptolemy
Claudius Ptolemy
(83 AD (est) -161 AD) was an Egyptian scientist and mathematician
of Greek descent who is best known for his influential work
Almagest,
a treatise
on mathematics
and astronomy published in 150 AD (est).
In Almagest, Ptolemy proposes a theory on the motions
of planets which would later become known as the Ptolemaic
System. This theory, which posits that all celestial bodies
revolve around the Earth, would become the foundation of
Western astronomy until Copernicus and the
heliocentric
theory .
The Ptolemaic System,
although based on false assumptions, was a extremely
effective at predicting the movements of the bodies of our
solar system. It was in part due to these accurate
predictions that the Ptolemaic System was accepted as
valid science for over a thousand years.
