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How the Geocentric Model of the Universe Worked [Video]

The ancient cosmology could explain the apparent motion of the planets using just their movements around circles

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In “The Case against Copernicus,” authors Dennis Danielson and Christopher Graney detail the evidence-based reasons why 17th-century astronomers doubted the Copernican model of the universe, which held that Earth revolves around the sun (and not the other way around). After all, the ancient geocentric universe of Ptolemy was able to account for the observed motion of the sun, moon and planets by using the complicated motion of epicycles—circles embedded within circles. The dispute was only resolved hundreds of years later, as apparent problems in the Copernican universe could only be resolved with the conceptual and experimental advances of the 17th- and 18th-centuries. In this video we see just how intricate the Ptolemaic universe was.

Michael Moyer is the editor in charge of physics and space coverage at Scientific American. Previously he spent eight years at Popular Science magazine, where he was the articles editor. He was awarded the 2005 American Institute of Physics Science Writing Award for his article "Journey to the 10th Dimension," and has appeared on CBS, ABC, CNN, Fox and the Discovery Channel. He studied physics at the University of California at Berkeley and at Columbia University.

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Scientific American Magazine Vol 310 Issue 1This article was published with the title “How the Geocentric Model of the Universe Worked [Video]” in Scientific American Magazine Vol. 310 No. 1 ()
doi:10.1038/scientificamerican012014-1nRHQAVyn5afTUMn2C50ok

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