Copernicus

Copernicus produced a new theory published in 1543 that had the Sun at the centre but in other respects it was similar to the Ptolemaic theory with its circles and epicycles.

He thought his model was simpler because many of the epicycles were smaller, even though there were just as many as in the Ptolemaic theory. We now know that this is because the Ptolemaic theory with the Earth at the centre required larger epicycles to 'take out' the Earth's motion round the Sun. In other words in the Ptolemaic model the Sun's orbit was the 'reverse' of the Earth's orbit. To that extent the Copernican theory was simpler.

Kepler's theory of 1609 did away with all the old circles and replaced them all with elliptical orbits for the planets, each one in its own plane, close to the ecliptic. He retained the idea that the Sun is at the centre, and devised the Three Laws of planetary motion.

After a full dynamical theory was produced by Newton that explained the elliptical orbits and Kepler's Laws, more and more people accepted that it was right, and that is the situation today, with tiny corrections due to Einstein's General Theory of Relativity.

Copernicus produced an alternative model of the planets that had the Sun at the centre, which contradicted the religious view at the time. The church was unwilling to change its theology without adequte proof.

The wisdom of the church's attitude was eventually proved when Copernicus's model was rejected in favour of one discovered by Kepler with elliptical orbits. It also had the Sun at the centre, and when the elliptical orbits were confirmed by Newton's theoretical discoveries the model was generally adopted.

The only part of Copernicus's theory that Kepler retained was the idea that the Sun is at the centre of the Solar System.

Copernicus's system used circles and epicycles, just like the ancient Ptolemaic system, with the difference that by placing the Sun at the centre Copernicus could simplify the complicated paths taken by the planets through space.

Kepler had the advantage of new accurate observations made by Tycho Brahe at the end of the 16th century, and these enabled Kepler to realise that by using elliptical orbits for the planets, the modelled positions could be fitted more closely with the measured positions.

Kepler retained the idea of having the Sun at the centre and it is the model used today with slight modifications from Einstein's theory of relativity.

People at the dark ages, were taught that the earth was the middle and the sun circled around it. Copernican heliocentrism is the name given to the astronomical model developed by Nicolaus Copernicus and published in 1543. It positioned the Sun near the center of the Universe, motionless, with Earth and the other planets rotating around it in circular paths modified by epicycles and at uniform speeds.

He did not go to jail and was never charged with any crime. He produced a new and in some ways better model of what we call the solar system. It had the Sun at the centre, and he was nervous that it might get him into trouble with the Church (his employers), so publication of his book on the subject was delayed until the year he died, 1543.

Kepler completely replaced Copernicus's theory of the orbits of the planets, which was based on circles an epicycles, with a new theory using elliptical orbits. However Kepler retained Copernicus's idea of placing the Sun at the centre.

Copernicus devised a new model of the planets' movements among the stars. To do this he made modifications to the ancient Ptolemaic system.

Copernicus considered that the ancient model was geometrically complicated and that it could be simplified very much by placing the Sun at the centre, instead of the Earth.

This was controversial because the Ptolemaic model had been around for well over 1000 years and had been incorporated into the scriptures, and it was believed the Earth is at the centre. Not only was it believed but it was also religious dogma.

In the end Kepler came up with a new model of elliptical orbits that was shown to be right many years later after the law of gravity and the laws of motion had been discovered. Kepler's theory is the one that is still in use today.

Kepler's theory retained Copernicus's idea of placing the Sun at the centre, so Copernicus was proved right in the end, although during Copernicus's lifetime he had no way of knowing it.

Both systems have the Sun at the centre, but Copernicus stuck to the ancient model of circles and epicycles to explain the planets' orbits.

Kepler on the other hand used new measurements by Tycho Brahe to suggest, after a lot of detailed calculations, that the planets move in elliptical orbits.

The difference between an ellipse and a circular orbit with an epicycle is extremely small in the case of planetary orbits which have a low eccentricity factor. It was not until Tycho came along that measurements of sufficient accuracy were available for Kepler to make his discovery.

Later the elliptical orbits were explained theoretically, after the discovery of the law of gravity and the laws of motion. This eventually led to Kepler's theory being generally accepted as right, which it still is.

Copernicus changed the accepted heirarchy in the universe by producing a new model of the planets' movements among the fixed stars, as they were called.

The accepted model by Ptolemy, who lived in the Roman Empire, had the Earth at the centre of everything, with the Moon, Sun and everything else orbiting round it. The old model used circles and epicycles to explain the planets' orbits round the Earth (an epicycle is a small circle whose centre moves round a larger circle).

Copernicus devised an alternative model with the Sun at the centre instead, with the planets including Earth in orbit around it. He found that the new model required smaller epicycles, much small for Mercury, Venus and Mars, and this made him think it was preferable because the orbits were much closer to a simple circular shape instead of the complicated paths of the Ptolemaic system.

Copernicus did not publish the new model until the year he died, 1543, because he knew it was contrary to current religious teaching and he had no way of finding which model was more correct because both models represented the planets' movements reasonably accurately. But his work encouraged other scientists who came after him to study the problem, and the model that finally gained acceptance was Kepler's model, published in 1609, which did away with the old circles and epicycles and used elliptical orbits instead.

Kepler retained the idea of putting the Sun at the centre and this model was later accepted after it was explained by the laws of motion and the law of gravity.

he used mathmadics to show the sun...

this hopefuly helped if you were in apex

Galileo used more advanced technology to find stronger observational evidence than Copernicus was ever able to provide.

His views went against traditional beliefs, including those of the Roman Catholic Church.

He did get into trouble. The church exiled him and excommunicated him. He killed himself afterwards.

Kepler's model of 1609 was more accurate than Copernicus' model of 1543 because it provided a more accurate fit to measurements of the planets' positions made by Tycho Brahe at the end of the 1500s. However, both models predicted the planets' positions fairly accurately, as did the ancient theory produced by Claudio Ptolemy (90-168).

Kepler's model, which has the planets in elliptical orbits, became accepted as right after it was later demonstrated that the elliptical orbits were the result of the newly discovered law of gravity. Kepler's model is used today.

The discovery did not support Copernicus's theory directly but it raised doubts about the ancient theory of Ptolemy that said that all objects in the sky are in orbit round the Earth.

Galileo was an aggressive supporter of Copernicus's theory but eventually it was Kepler's theory that became accepted and is still used today. Both Copernicus and Kepler placed the Sun at the centre but Kepler's elliptical orbits are supported by the later theory of dynamics.

Copernicus published an alternative model of the planets' movement in 1543 that had the Sun at the centre. It was the first heliocentric model. It used orbits based on combinations of circles, as the ancient Ptolemaic system had done, which was geocentric.

In Copernicus's model the paths followed by the planets were less complicated, but other than that Copernicus had no way of proving if it was right or not at that time, so it isn't known whether he believed in it.

The modern theory is the one devised by Johannes Kepler. It uses the heliocentric idea, as Copernicus's model did, but Kepler rejected the circles and epicycles used by Copernicus and Ptolemy before him, and used elliptical orbits for the planets instead.

Kepler's model was published in 1609, and it was realised quite quickly that it represented the movements of the planets more accurately than the old models. But the old models were not bad and their inaccuracies were demonstrated only after Tycho Brahe built new, accurate measuring systems in the late 1500s. Kepler used Tycho's observations.

With 3 systems in play that were all reasonably accurate there was no way of deciding the best one, although Kepler's model was slightly better.

But in the late 1600s Isaac Newton had built on previous work to produce the law of gravity and the laws of motion. He was able to show that a planet in the Sun's gravity field must move in an elliptical orbit. This was the clincher that made people accept Kepler's model.

Copernicus was employed by the Church and was reluctant to publish work that contradicted the scriptures. Publication of his book was delayed until the year he died, 1543.

No, that is what he didn't do. Ptolemy had already done that and basked in the glory for 1400 years. Copernicus thought that the planets' orbits could be explained more simply by considering the Sun as being at the centre, which would need fewer violent movements on the part of the planets to explain the way they move. So his 'De Revolutionibus' book published in 1543 had a new model that still used circles and epicycles, but had the Sun at the centre and smaller epicycles, especially for Venus and Mars.

1543 was also the year Copernicus died, and he was nervous about publishing the book because he knew the church's teaching at that time went along with the Bible in saying the Earth is fixed at the centre of the universe.

The later theory we use today still has the Sun at the centre, but all the old circles were thrown out by Kepler who hit on the idea of elliptical orbits instead.

he provided observational something

The church believed that the earth was at the center of the universe.

You don't tell us which choices you were given, so we can't help you.

I think that Copernicus preferred to work alone because what he thought went against common religious beliefs.

Copernicus put forward the idea that the Sun, rather than the Earth, was at the center of the universe.