Question

Why did Copernicus and Kepler advocate the new heliocentric theory?

Answer 1

Solution:

According to heliocentric theory , sun is at rest , at the center of the universe, with the Earth and other planets revolving around it.

The contested state of the Planetary theory of the late 15th Century and Italian Philosopher Pico's criticism of the Astrology's foundations of those days together constitute the actual historical background for Copernicus's achievement of helio centric theory. In Copernicus time, Astrology and Astronomy were considered as the subdivision of a common subject called the Science of the Stars.The Planetary model of those years , (mainly of Aristotle ) ,was questioned and criticised by Pico, since it could not account for the variation in the apparent brightness of the Planets and the wobbling of planets .Ptolemy solved that problem by proposing three mechanisms.Persian astronomers of the 13th century at Maragheh gave a theory of revolving epicycles that explained the equalized motion of the planets . Copernicus learnt about this model through an unknown intermediary link and developed an insight to resolve the conflict of wobbling planets .

To summarize, it was the works of Ptolemy , the criticisms of Pico about the Astronomical models of those years and the works /theories of epicycles of the 13th century Persian astronomers that influenced Copernicus into developing the sun centric or Helio centric model of the universe.

Kepler used the Astronomical observations of Tycho Brahe to define the orbits of the planets .But later used his own knowledge of geometry and proved that an imaginary line drawn from a planet to the Sun swept an equal area in space in equal times and developing this theory in opposition the Brahe's theory of circular orbits led to defining and proving the elliptical orbits of planets around the Sun.