According to a new study, Earth's collision with a Mars-sized protoplanet 4.5 billion years ago didn't just create the Moon. It also gave us our oceans and helped life get started.

Asteroids and comet brought our planet water and the chemical precursors for life. But could they have also given rise to our continents and help set plate tectonics in motion?

Scientists think they found a time capsule from Earth's earliest days buried just under the Moon's surface for the last 4.1 billion years.