-
4.6 billion years ago, earth's rocky core formed first, with heavy elements colliding and binding together.
-
at around 4 billion years ago, earth started the planetary cooling. This is when due to radioactive heat, there is continental drift on the surface. This source of heat on earth was lava. Lava had radioactive heat, which kept earth heated that way for some time.
-
About 4.6 billion years ago, the earth struck with a object called Theia. the lose pieces scattered and the moon formed from the collection of them. This was also the reason behind planetary cooling.
-
This is an event that happened 3.8-4 billion years ago. this is when intense comets would hit planets including earth. then this would allow all the planets to be formed in a certain way which is what we have now called the solar system.
-
At around 1-1.5 billion years ago the core of earth was being formed. It is said that the inner core once froze because of the surrounding molten iron from the iron core. The inner core is located in the center of the earth, providing heat.
