3r
Chat with our AI personalities
Nicolaus Copernicus was a Polish astronomer who is best known for the astronomical theory that the Sun was near the center of the universe and that the Earth and other planets rotated around the center. He also stated that the Earth spinning on its axis, rotates once daily and makes a full revolution around the Sun in a year. Copernicus did not believe that the Earth and other planets were influenced by or revolved due to the Sun, instead he believed that the Sun was located near the center of the universe. It was this center of the universe which influenced those bodies and caused them to revolve. This theory is called the heliocentric or sun-center theory of the universe.He believed in the theory that the Earth revolved around the sun and not the other way around. He didn't publish his findings until before his death because he was afraid of going against the church and of being persecuted.
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.
think, believe, suppose, assume, trust, imagine, reckon, presume, anticipate, predict, envisage, await, contemplate
I believe this answer to be 10C5. Due to the fact there are 10 numbers to chose from, and you want to know how many times they can be aranged using 5 numbers. The answer is therefore, 10!/5!(5!), which is 252.
5