was born in Greece who worked most of his life in Alexandria, Egypt. He was
a brilliant mathematician, geographer and astronomer whose theories dominated
the Western world until about the 16th century.
He believed the stars were static and worked out a geometric method to define the motions and positions of the Sun, moon and planets. He also believed that the Earth was a sphere and the centre of the Universe, with the other heavenly bodies circulating around it.
Ptolemy also contributed to trigonometry, and and combined astronomy with astrology, wrote a book on geography, influencing map makers for centuries after. He studied light and created a theory on music as well.