The leading explanation for all of these mysteries is known as the giant impact hypothesis. According to this story, when the ...

So, if the moon didn't form with the Earth, where did it come from ... believe the moon formed when the young Earth was struck by another planet (dubbed Theia for the mother of the Greek moon ...

So what causes a lunar eclipse, when is the best time to view this one—and how did it get ... moon orbits the Earth and the Earth orbits the sun, the three bodies are forever getting in one ...

The total angular momentum of Earth's spin, the moon's spin and the moon's orbit is very large — far higher than for any other terrestrial planet. So how did we get so much momentum? Plus ...