Part 4 - The Birth of a Planet

So now we have all the elements, hydrogen & helium atoms, other free particles and photons in the universe. In certain places there was a higher concentration of matter and therefore gravity here would be stronger. Other bits of matter will be attracted to these areas due to the force of gravity. These concentrations of matter consisted of both gas and solid, and the centre became so hot that the solid evaporated, leaving behind a mixture of elements that began to glow, giving off heat and light. Our sun is one such star that formed in such a manner.

As the sun was forming, it was also swirling at a high speed. This caused the sun to throw off some of the substance around it. This matter that was hurled into space combined with the other matter already in space and formed our planets., which orbit the sun. The smaller inner planets are formed of heavier elements and the outer planets are larger and are largely of various gases.

This was how earth formed. Most of the heavier elements like iron and whatever was attracted to it sank to the centre and the lighter elements and whatever was attracted to it rose to the surface. With all the pressure, friction and radiation, the earth was a molten ball. But the earth cooled over millions of years, and the hot core is now miles below the surface. It ocassionally breaks through in places like volcanoes. Earth's surface cooled into a hard crust, consisting of mainly lighter materials. In fact, the different continents that we have are really just giant plates of stone floating around very slowly on the surface of that molten core.

So we live on the surface of the earth. And many of us don't have a clue as to how the earth came about. In fact living on the surface, things don't seem at all like what's described above.

So what was our planet like in its infancy?