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Discoveries > Ptolemy


Here the motion of planets as supposed by Ptolemy (100-170) in the second century after J.-C.  He was at the origin, for more than fourteen centuries, of the erroneous idea that the Earth was stationary at the center of the universe.
Ptolemy following the motion of the celestial bodies, using "quadrants".
(Campanile of the Cathedral of Florence)

Ptolemy is a Greek astronomer who lived in Egypt in Alexandria. He takes up all the ancient science in his book Almageste which will allow calculate the positions of the celestial bodies and which will remain the reference until the end of the Middle Ages.

Ptolemy is astronomer and geographer. He makes a map of the inhabited world which uses all the information known at the time. It takes up the sexagesimal system of the Babylonians which will be continuouly used until now.