Question: how did the world start?

Ozge Ozkaya answered on 14 Jun 2011:

Hi Jess,

I am not an astrophycisist but here: The earth was formed 4.6 billion years ago by what’s called accretion which is the collision and sticking of minute dust and ice particles together becoming bigger and bigger and attracting more particles by gravitation. The oldest rock found on earth is 4 billion years old. The earth’s surface was then bombarded by meteorites and there must have been severe volcanioc activity too. About 3.8 billion years ago primordial life began to evolve on earth. 2 scientists Oparin and Haldane thought that those conditions favoured chemical reactions that synthesised organic compounds such as amino acids (which are the building block of all microorganisms, animals and plants) from inorganic matter. In 1952, 2 other scientists Miller and Urey conducted a very famous experiment that simulated the conditions of the primitive earth and managed to obtain amino acids in the lab!!