What's carving active gullies on Mars? It's not water

Scientists were shocked when they received the first images of Martian gullies. They were even more shocked as those gullies appeared to change over time. Their similarities to gullies seen on Earth were uncanny, but all of Earth's gullies are formed by water runoff, and Mars is This story matters for Science & Discovery readers tracking science. Reported by phys.org. Read the full original at the source link below.