The idea of Earth circling the sun is universally accepted today, but this was not always the case. Centuries ago, it was widely believed that the earth stood still and the sun moved. Many years before the invention of the telescope, Copernicus worked with primitive scientific instruments to prove that Earth revolved around the sun. At first, he was denounced and ridiculed for this belief. Later, scientists with more advanced instruments proved that Earth did indeed revolve around the sun. Many of our modern advances in science would not have been possible without the heliocentric theory of Copernicus. This revised edition is now in full color.