The discovery that the Earth revolves around the Sun, or the heliocentric model of the solar system, was the first major change to ancient models. This revolutionary idea was proposed by the Polish astronomer Nicolaus Copernicus in the 16th century. His publication "De Revolutionibus Orbium Coelestium" in 1543 presented the heliocentric model and challenged the widely accepted geocentric model, where Earth was considered the center of the universe. Copernicus's model laid the foundation for modern astronomy and marked a significant shift in our understanding of the solar system.
