Geocentric model coelestium" ("On the Revolutions of the Heavenly Spheres"), which posited that the Earth and the other planets instead revolved around the Sun. The geocentric system was still held for many years afterwards, as at the time the Copernican system did not offer better predictions than the geocentric system, and it posed problems for both natural philosophy and scripture. The Copernican system was no more accurate than Ptolemy's system, because it still used circular orbits. This was not altered until Johannes Kepler postulated that they were elliptical (Kepler's first law of planetary motion). With the invention of the telescope in 1609,
Central Illinois Regional Airport for the Central Illinois Air Derby. Billed at the time as the greatest such event in Illinois outside of Chicago, the show included four U.S. Army "ships" from Chanute Field in Rantoul, civilian aviators from places like Aurora, Champaign, Joliet and Kankakee, aerial "stunting" contests and races, parachutists and an air parade over downtown Bloomington. Despite the efforts of local aviation enthusiasts and the business community, attempts to establish long-term passenger service at the Normal field ended in failure. In the fall of 1931, Century Air Lines added Bloomington to its Chicago-to-St. Louis route, and the little grassy square (recently