Our planet has had a difficult and violent past. The potential for life all begins when Earth collides with another protoplanet, the size of Mars, shortly after the formation of our solar system. The impact nearly destroys our home, but Earth survives. And in the end a new world was created: The moon. Although it causes a lot of trouble on Earth, it is the moon that plays an important role in the story of how life ultimately came to be on our planet.