So how did our planet end up with such a special moon? The answer is that, surprisingly enough, the moon is a piece of our ...

The ball hangs in the void ... In orbit around the white planet is a single cratered moon. You are gazing on Earth in the Cryogenian period, 700 million years ago. This is about three times ...

Obviously, if the giant asteroid Apophis were to collide with something else on its way to Earth, its path could change, or a field of debris could indeed hit the planet. To see if that was ...

The leading explanation for all of these mysteries is known as the giant ... a molten ball, more than enough to bring the KREEP elements together, and more than enough to mix Earth's original ...