Timeline

o 15 billion years ago the universe was formed from a atom that consisted of all the matter and energy that exists today.

o About 4.6 billion years ago shockwaves caused the solar nebula (dust and gas that developed into our solar system) to contract.

o As the solar nebula condensed its temperature increased and began forming the Sun.

o 1% of the material that is not part of the sun began to condense and form small bodies of matter called planetesimals.

o The planetesimals joined together through collisions and the force of gravity to form larger bodies called protoplanets. Protoplanets acted like giant magnets, pulling more planetesimals towards themselves.

o The Earth was formed.