A model of the universe that places Earth at its center is called the geocentric model. This concept, which dates back to ancient civilizations, was most famously formulated by the Greek philosopher Claudius Ptolemy in the 2nd century AD. In the geocentric model, celestial bodies such as the sun, moon, and planets were believed to orbit around Earth, which was viewed as the center of the universe. While the geocentric model provided a framework for understanding celestial movements for centuries, it was ultimately replaced by the heliocentric model proposed by Copernicus in the 16th century, which positioned the sun at the center of the solar system.