who was ptolemy? and what did he do/what was he famous for? what website can i find info on him???

Answer 1

Ptolemy was a Greek mathematician, musician, astronomer and astrologer.
He is best known for the Ptolemaic system of planets. He believed that the earth was at the center of the Universe and that all other celestial bodies (including the sun) rotated around it. This created problems with observations, because planets would sometimes recede (Go in the opposite direction), because Earth would pass them, and they would look as though they were going backwards for a while.
So Ptolemy devised a system of epicenters to explain those backward movements. Epicenters are orbital circles around existing orbits. So in other words, Mars would go around the earth, but because it turned back at certain times, there would be another circle in the drawing to explain Mars went around that circle, which was attached to the bigger circle.
This cause major problems over time in astronomy, because the system would get increasingly complicated with more circles going around smaller circles to explain more precise movement.
Eventually, the system was let go for heliocentric (With the sun in the middle) models, because of their simplicity and the fact they better explained observation. Kepler, Copernicus and Galileo participated in overturning the Ptolemaic system and introducing heliocentric ones.

Eldoreefgold is also right - there was a General of Alexander by the name of Ptolemy. These are different people. It depends which one you want.

Answer 2

He was a Greek mathematician and astronomer.

Wikipedia is always a good place to start:
http://en.wikipedia.org/wiki/Ptolemy

Answer 3

one of alexander the great's generals who was given the satrap of egypt to rule upon alexander's early death without progeny!!cleopatra for this reason ,in his lineage,may be considered as more greek than egyptian!!alexander was more properly macedonian and it was his father phillip who had desired to unify greece as well as the known world under his rule ,even against the vast territories and armies of the persian empire and it's kings of kings xerxes and later darius!!

Answer 4

http://search.yahoo.com/search?p=Ptolemy&fr=ush-ans

Start at the above.

Answer 5

Try these

en.wikipedia.org/wiki/Ptolemy

ptolemy.eecs.berkeley.edu

www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Ptolemy.html