SOLAR SYSTEM

Detailed explanation-1: -The Big Bang was the moment 13.8 billion years ago when the universe began as a tiny, dense, fireball that exploded. Most astronomers use the Big Bang theory to explain how the universe began.

Detailed explanation-2: -According to the Big Bang theory, the expansion of the observable universe began with the explosion of a single particle at a definite point in time. Georges Lemaître, (1894-1966), Belgian cosmologist, Catholic priest, and father of the Big Bang theory.

Detailed explanation-3: -The Big Bang theory, developed in 1927 is considered the most credible scientific explanation of how the Universe was created. It suggests that through a process of expansion and explosion hydrogen gas was created which led to the formation of stars, and their death (supernova) led to the creation of life.