GENERAL KNOWLEDGE

Detailed explanation-1: -Ptolemy accepted Aristotle’s idea that the Sun and the planets revolve around a spherical Earth, a geocentric view. Ptolemy developed this idea through observation and in mathematical detail.

Detailed explanation-2: -Key facts. Claudius Ptolemy was a 2nd century Greek mathematician, astronomer and geographer famous for his controversial geocentric theory of the universe, which would form the basis of our understanding of the motions of stars and planets for over than a thousand years.

Detailed explanation-3: -The Copernican Revolution At the beginning of the 16th century, Nicolaus Copernicus challenged the geocentric model and proposed that the Earth and other planets revolve around the sun.

Detailed explanation-4: -The most important solution to this problem was proposed by Claudius Ptolemy in the 3rd century AD. He argued that planets move on two sets of circles, a deferent and an epicycle. This explained retrograde motion while keeping the planets in their circular orbits around the Earth.