Question

When and how was the Earth formed?

Answer 1

According to the big bang theory Anything in this world was formed after the ginormous explosion which is known as Big Bang explosion .

Around 4.5 billion years ago there was a collision of two heavenly bodies which led the formation of earth as well as moon .

Answer 2

Earth formed around 4.54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula. Volcanic outgassing probably created the primordial atmosphere and then the ocean, but the early atmosphere contained almost no oxygen.