Theory that the Sun rather than Earth is at the center of the universe. The heliocentric theory of the universe was originally proposed by the Greek philosopher Aristarchus of Samos. Around the year 280 B.C.E., Aristarchus suggested that Earth revolves around the Sun in common with the other planets an idea that had been considered by the Pythagoreans a few centuries before as a feasible alternative to geocentrism. The competing geocentric theory, that Earth formed a stationary center and the rest of the universe revolved around it, was given precedence by such major philosophers as Aristotle and Ptolemy. When the Christian church accepted Aristotle’s ideas as truth, it also accepted his geocentric model of the universe. This meant that any future thinkers who questioned the truth of the geocentric model would face possible condemnation by the church authorities.<\/p>\n
If the geocentric model of the universe had been without practical application, the theorizing might have stopped there. However, seagoing merchants used Ptolemy\u2019s Almagest, a series of star tables, to calculate the positions of their ships. The church itself used the stars to regulate its calendar, which contained some important feast days, such as Easter, that had to be calculated and recalculated each year. Ancient astronomers and mathematicians had modified the original geocentric theory to account for observed variations in the motion of the planets and the stars. Ptolemy himself introduced a theory of epicycles to explain why some planets appeared to move backwards at certain times of the year.<\/p>\n
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Theory that the Sun rather than Earth is at the center of the universe. The heliocentric theory of the universe was originally proposed by the Greek philosopher Aristarchus of Samos. Around the year 280 B.C.E., Aristarchus suggested that Earth revolves around the Sun in common with the other planets an idea that had been considered […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-210821","post","type-post","status-publish","format-standard","hentry","category-h"],"yoast_head":"\n