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'''Heliocentrism''' is the view that the sun is at the center of the solar system or the universe or both. Prior to modern times there was no real distinction between the center of the solar system and the center of the universe.  Heliocentrism was originally proposed by the ancient Greeks<ref>Aristarchus of Samos (ca. 310-230 BC) proposed it, Archimedes discussed it, and the idea was well-known in Europe when [[Copernicus]] proposed a heliocentric model of the solar system. [http://galileo.rice.edu/sci/theories/copernican_system.html]</ref>.   

'''Heliocentrism''' is the view that the sun is at the center of the solar system or the universe or both. In ancient times there was no real distinction between the solar system and the universe.  Heliocentrism was originally proposed by the ancient Greeks<ref>Aristarchus of Samos (ca. 310-230 BC) proposed it, Archimedes discussed it, and the idea was well-known in Europe when [[Copernicus]] proposed a heliocentric model of the solar system. [http://galileo.rice.edu/sci/theories/copernican_system.html]</ref>.   

The heliocentric view of the universe became less and less popular during the course of the 1700s and 1800s. It was completely abandoned by the 20th century.

The heliocentric view of the universe became less and less popular during the course of the 1700s and 1800s. It was completely abandoned by the 20th century.