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General
Copernicus, Nicolaus (1473-1543)
Galileo Galilei (1564-1642)
Einstein, Albert (1879-1955)
Hipparchus (c. 180-125 BC)
Hubble, Edwin P. (1889-1953)
Jansky, Karl (1905-1950)
Kepler, Johannes (1571-1630)
Newton, Issac (1642-1727)
Shapley, Harlow (1885-1972)
Hawking, Stephen (1942-1998+)

Claudius Ptolemy was an Alexandrian astronomer, mathematician and geographer. He based his work on the belief that all heavenly bodies rotate around the earth.

LINKS
Information on the work of Ptolemy including pictures, diagrams and links
http://seds.lpl.arizona.edu/nineplanets/psc/theman.html

Description of the Ptolemaic System
http://es.rice.edu/ES/humsoc/Galileo//Things/ptolemaic_system.html

Information on the astronomical work of Ptolemy
http://www.cinemedia.com.au/SFCV-RMIT-Annex/rnaughton/PTOLEMY_BIO.html

Biography of Ptolemy and equations to do with his work
http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Ptolemy.html

Information and links to nine famous Alexandrian mathematicians including Ptolemy
http://aleph0.clarku.edu/~djoyce/mathhist/alexandria.html