How was Copernicus' model of the universe different from Ptolemy's model?

Answer 1

The main difference was that Ptolemy's model was geocentric (Earth-centred) and Copernicus's was heliocentric (Sun-centred). Ptolemy's model came from ancient times while Copernicus's was much later (1543).

Both models represented the planets' orbits by using combinations of circles and epicycles to explain the way the planets move among the stars.

Copernicus found that the orbits of the inner planets could be explained more simply. That is to say that the epicycles used for all the orbits were smaller, and for the inner planets a lot smaller.

Both models represented the planets' positions with reasonable accuracy given the crude observational methods used in those days.

Until gravity and the laws of dynamics were discovered about 150 years after the publication of Copernicus's system, there was no way of deciding which model was the 'right' one.

Answer 2

Copernicus's model thought that the planets orbited the sun. Ptolemy's model thought that the planets orbited the moon.

No. The above answer is incorrect.

Copernicus's model thought that the planets orbited the sun. Ptolemy's model thought that the planets orbited the EARTH in epicycles. Not the moon. (The model that modeled the planets orbiting earth was the Geocentric model. Aristotle theorized this.)

Copernicus's model is known as the Heliocentric model. Ptolemy's theory of epicycles is when the planets revolved in large circles around Earth.

Answer 3

The main difference was that Ptolemy's model was geocentric (Earth-centred) and Copernicus's was heliocentric (Sun-centred). Ptolemy's model came from ancient times while Copernicus's was much later (1543).

Both models represented the planets' orbits by using combinations of circles and epicycles to explain the way the planets move among the stars.

Copernicus found that the orbits of the inner planets could be explained more simply. That is to say that the epicycles used for all the orbits were smaller, and for the inner planets a lot smaller.

Both models represented the planets' positions with reasonable accuracy given the crude observational methods used in those days.

Until gravity and the laws of dynamics were discovered about 150 years after the publication of Copernicus's system, there was no way of deciding which model was the 'right' one.

Answer 4

Ptolemy's theory said that the Sun and other celestial bodies revolve around the Earth, which stays still. But Copernicus's theory was that the Earth moves around the Sun.

Answer 5

Copernicus' view was that the sun was the center. He believed everything revolved around the sun