For decades, scientists have been debating how would it be if a piece of Earth broke down and shaped our Moon about 4.5 billion years ago. Now, new chemical evidence directs science to the theory that events were actually much more turbulent than we had imagined. Scientists describe the impact that  “freed” the Moon using the metaphor “hammer struck a melon.” Science has established the theory that the Moon was once part of the Earth before it was cut off and sent into orbit, but the exact circumstances in which it happened were still unclear. So far, the popular theory...