History Of Earth Timeline
It is believed that the Earth, along with the other planets, was born 4,500 million years ago as a solidified cloud of dust and gases that remained from the creation of the Sun. For perhaps 500 million years, the Earth's interior remained solid and relatively fresh, perhaps at 2,000 ° F. The main ingredients, according to the best available evidence, were iron and silicates, with small amounts of other elements, some of them radioactive. As millions of years passed, the energy released by radioactive decay, mainly uranium, thorium and potassium, gradually heated the Earth, melting some of its components. The iron melted before the silicates and, being heavier, sank towards the center. This forced the silicates he found there. After many years, the iron reached the center, almost 4,000 miles deep, and began to accumulate. There were no eyes around at that moment to see the turmoil that must have taken place on the surface of the Earth: gigantic riots and bubbles on the surface, ...