The history of earth - how was the earth formed, how life began on earth

<p>Earth and the other planets formed about 4.6 billion years ago. they were made of the leftover gas from the nebula that made the sun. earth's rocky core formed first, with heavy elements colliding and binding together. dense material sank to the center, while the lighter material created the crust. the planet's magnetic field probably formed around this time. but scientists do not know how life began on earth.</p>