The Origin and Evolution of the Earth
Earth and the other celestial bodies in the solar system has always been a subject of fascination for all of us. People, since the early times were eager to know about the origin of Earth and the evolution of life on it.
The research to find the age of Earth started long back.
A large number of hypotheses were put forth by different philosophers and scientists regarding the origin of Earth.
Early theories include:
Revised Nebular Hypothesis
Planetesimal Hypothesis of Chamberlin and Moulton
Tidal Hypothesis of Jeans and Jaffreys
Modern theories are:
Big Bang Theory
Hoyle’s Concept of Steady State
The distributed matter in the universe came together due to the gravitational forces and formed the galaxies. A galaxy contains a large number of stars, which are formed from the clumps of gas developed in the nebula.
Sun, one of the stars of Milky Way galaxy and other celestial bodies, which are bound to it by gravity, forms the solar system. The celestial bodies include planets, asteroid belts, moons, comets and dwarf planets.
Our planet Earth evolved from a barren, rocky and hot object, to a beautiful planet with ample amount of water and conducive atmosphere favouring the existence of life. Life on Earth began to evolve about 3,800 million years ago.