No, both the systems that Galileo knew about were based on circular motion. The geocentric Ptolemaic system and the heliocentric Copernican system both used complex systems of circles and epicycles to describe the planets' movements, and these models were reasonably accurate.
It was Kepler who started to use the idea of elliptical orbits after Tycho Brahe made new and accurate measurements that showed faults in predictions made by the two old systems.
Keplers detailed mathematical work was purely descriptive, in that his new model described the planets' positions in the sky more accurately than ever before, but he did not know why his model should be as accurate as it clearly was.
Later, Newton produced a new theory explaining why the planets would be expected to move in elliptical orbits under the force of gravity. That is the modern model of the solar system, with slight adjustments after Einstein's general theory of relativity.
went* Galileo
I believe that would be Galileo (sp?) However I'm pretty sure Kepler is the one that proved it.
The planets in our solar system have an elliptical (oval) orbit around the Sun. This orbital shape is a result of the gravitational forces between the planets and the Sun. Planets closer to the Sun have shorter and more circular orbits, while those farther away have longer and more elliptical orbits.
coperincus
Galileo
Elliptical orbits of the planets around the sun actually match what we observe. Newton's Theory of Universal Gravitation states that planets will move around the sun in elliptical orbits.
Planets circle in an elliptical orbit around the Sun.
he stated that planets went around the sun
went* Galileo
galileo did because he proved that all the planets revolved around the sun......NOT THE EARTH!!
I believe that would be Galileo (sp?) However I'm pretty sure Kepler is the one that proved it.
Galileo thought planets revolved around the sun because when he observed Jupiter, he noticed that its moons revolved around Jupiter and not earth. So everything else led up to that the Earth revolved around the sun.
The orbits of the planets around the Sun are not spherical as many people imagine but are in fact elliptical.
All the planets move with an elliptical orbit, but with a very low eccentricity.
As an elliptical orbit is any orbit that isn't perfectly circular, everything has an elliptical orbit. The planets Mercury and Pluto have the most elliptical orbits of the planets, and are easily seen to be oval shaped. Comets also have highly elliptical orbits.
Galileo's observation was that all the planets revoled around the earth and he though earth was a middle planet
Galileo Galilei