New research has uncovered a striking link between the structure of our galaxy and the evolution of Earth's crust, showing its development was shaped by the impact of meteorites during its journey through the Milky Way.
The history of water on early Mars is not certain. Determining when water first appeared, where and for how long, are all burning questions that drive Mars exploration.
New research finds Earth's surface was first sprinkled with fresh water some 4 billion years ago, a whole 500 million years earlier than previously thought.