地心说, or the geocentric model, is an ancient astronomical theory that posits the Earth as the center of the universe. According to this model, all celestial bodies, including the 太阳 (Sun) and 月亮 (Moon), revolve around the Earth. This view was widely accepted in many cultures, including ancient Greece and medieval Europe. The geocentric model was notably advanced by the Greek philosopher 亚里士多德 and later refined by the astronomer 托勒密. However, it was eventually challenged and replaced by the 日心说, or heliocentric model, proposed by 哥白尼, which correctly identified the Sun as the center of the solar system.