The Road to Life
1 Scientist generally think the Earth came into existence 4.6 billion years ago. if you could have seen it back then, you wouldn't have recognized it;it wouldn't have looked anything like the Earth we know. So what did it look like? And how did the Earth start to support life?
For the first 700 million years, huge pieces of solid rock floated in a sea of magma-the same magma that comes out of volcanoes as lava today. This cooling magma released water vapor, creating the oceans. However, there was no oxygen, and the air couldn't support life.