Âm thanh chia sẻ

And yet… something unexpected began to happen. As the planet slowly cooled, vapor in the atmosphere started to condense. Clouds formed. Then… rain. Not for days… or years… But for millions of years. Water began to accumulate, forming the first oceans. Some scientists believe that part of this water came from space — carried by comets and icy asteroids. Slowly… Earth began to change.