How has the theory of solar system changed?
The theories of the solar system have changed quite a lot over time. Most theories before the 15th century said that the earth was at the center of the universe. Some of them thought that there was a fixed dome around the earth on which the stars were fixed, and that the dome moved. However, it was very clear very early on that the planets did not move like the stars, and they were given special status. However, the calculations for the movement of the planets, which would sometimes go one way in the sky, sometimes the other way, got more and more complicated. People like Kepler and Copernicus then proposed a simpler means of calculation, which was to put the sun at the center. Therefore mathematical and conceptual elegance, not technology, led to the Copernican revolution, although then Galileo later used telescopes to confirm the Copernican model. As telescopes and computers got better, more planets were added, until there were 9 planets. Then telescopes got even better, and it was d
