Claudius Ptolemy was a Roman citizen of Egypt who wrote in Greek. He was a mathematician, astronomer, geographer and poet,
His book, The Almagest, described the solar system as ‘geocentric’ meaning earth-centered. He believed that the sun, moon and planets all revolved around the earth in perfect circles, which readily explained the apparent motion of the sun and moon, but not the planets. The Greeks considered the circle to b ea pure and perfect shape; thus all orbits around the earth were deemed to be perfectly circular.
This geocentric model served as the predominant cosmological system in many ancient civilizations such as ancient Greece.
Ptolemy’s geocentric model was not seriously challenged until the sixteenth century. Then Polish mathematician named Nicolaus Copernicus described a heliocentric model that place the sun at the center of solar system.
Geocentric model of the solar system by Ptolemy
