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Geocentrism

Astronomy

Geocentrism holds that Earth sits still at the center of the universe while the Sun, Moon, planets, and stars all orbit around it. Claudius Ptolemy's Almagest, completed around 150 CE, gave the model its most complete mathematical form, predicting planetary positions accurately enough that it dominated Western and Islamic astronomy for over 1,400 years. It began to give way after Copernicus published a heliocentric alternative in 1543, and lost the argument decisively once Galileo's telescope showed the phases of Venus in 1610 and nineteenth century measurements of stellar parallax directly confirmed that Earth moves. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Proposed Year
150 1
Sourced to the subject's own accountDated to Ptolemy's Almagest, the model's most complete and influential statement; geocentric ideas in Greek astronomy are centuries older still, so this year marks the model's definitive form, not its first appearance.
Proposed BySourced to the subject's own account
Claudius Ptolemy, formalizing centuries of earlier Greek astronomy 1
Connections

Belongs To

Astronomy, Disciplines
Sources
1. Geocentrism (Wikipedia)
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