Who discovered that the Earth is not the center of the universe?

In ancient times, most people believed that Earth was the center of the universe. This idea, called the geocentric model, was supported by philosophers such as Aristotle and later developed by Ptolemy. According to this model, the Sun, Moon, planets, and stars all revolved around Earth in circular paths. While this explanation seemed to fit everyday observations, it could not accurately explain the motion of planets.

The turning point in science came with Nicolaus Copernicus (1473–1543), a Polish astronomer, who introduced the heliocentric theory. This theory stated that the Sun is at the center of the solar system, and Earth, along with other planets, revolves around it. Copernicus published his ideas in the book De revolutionibus orbium coelestium in 1543. His model explained planetary motion more clearly and opened the door to modern scientific understanding of space.

Looking at the options:

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  Aristotle believed in a geocentric universe, so his view was incorrect.

  
  


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  Nicolaus Copernicus (Correct Answer) introduced the heliocentric theory.

  
  


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  Sir Isaac Newton came later and explained planetary motion with the law of gravitation but did not propose the heliocentric idea.

  
  


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  None of these is incorrect because Copernicus is the correct choice.

  
  

Copernicus’s discovery was revolutionary. It challenged centuries of belief and influenced later scientists like Galileo Galilei, who confirmed the heliocentric theory with his telescope, and Johannes Kepler, who refined it with mathematical laws. Eventually, Newton explained why planets stay in orbit, completing the scientific picture.

This shift from Earth-centered to Sun-centered understanding is one of the greatest milestones in Everyday Science. It not only changed astronomy but also reshaped human knowledge of the universe, showing that scientific truth can replace long-held misconceptions.