The Copernican Revolution:

It was right in the midst of these developments in the fifteenth century, that there came the first major break from the whole system of ancient thought. This was the work of Copernicus, who gave a  clear and detailed  explanation for the rotation of  earth and other planets on their axis and  their motion around a  fixed sun which was at the centre. This model simplified astronomical calcuhtions, and also made them more precise. In such a model had been proposed  by Greek astronomers like Aristarchus many centuries earlier. However,  it was not given any importance because it ran counter to the established  ideas of  those times. This work of Cope~nicus  was published in  the very year of his death in  1543. Although  his book attracted  limited attention and there were objections  to his model, his work-gave a great boost  to further work by Galileo. We will  talk about Galilee's work later in Sec. This was the first phase of what we now call the Scientific Revolution. In  this phase, the old ways of thought were proving inadequate. By  rejecting the old ideas, the men of Renaissance had cleared the grounds for new ideas of the succeeding century. In the use of science for practical purposes too, the Renaissance set the scene for.  future developments. From now on science had become a necessity  for profitable enterprises,  trade and war.