Ptolemy's system of astronomy held up until 1543, when this Polish astronomer went heliocentric
In Copernicus' 
lifetime, most believed that Earth held its place at the ... Today, we call the model 
of the solar system, in which the planets orbit the sun, a heliocentric... [DOC] [TLE] Early Astronomers: Ptolemy, Aristotle, Copernicus, and Galileo ... [PAR] Early Astronomers: Ptolemy, Aristotle, Copernicus, and Galileo ... Nicolaus 
Copernicus came up with a radical way of looking at the Universe.