The surface of Mars is lined with mysterious deep-carved trenches. A long-standing theory suggesting that the were left long ago by flowing rivers was just debunked. So where did these trenches come from?
The Curiosity rover was sent up to Mars with the important job of hunting for microbes on the red planet’s surface. Now, that job is done, and Curiosity is getting a new mission — and that mission is all about the past, and future, of life on Mars.