Sun-Centred vs. Earth-Centred Universe - Assignment Example

People believed that Earth is a stationary object and other stars revolve around it since they never felt any sensation of movement on Earth. This is called the geocentric theory nowadays. During the 4th century, Greeks proposed that stars are fixed in a celestial sphere and other planets, sun, and moon are revolving underneath this celestial sphere. Many such models and concepts were proposed to prove this theory but finally, the Greek astronomers realized that there are some weaknesses related to this concept.

The concept of the Earth-Centered Universe was widely accepted until the theories proposed by Nicolaus Copernicus, Galileo Galilei, and Johannes Kepler. The heliocentric model was proposed by Copernicus which was based on the notion that Earth and other planets revolve around the sun. The retrograde motion was described clearly in this model and illuminated some more facts in favor of the notion that Earth is NOT the center of the universe.