We've heard quite a bit about Mars this week, what with this whole Curiosity business and all. But today, we got some other news about the red planet that may even help us understand Earth a little better. An Yin, a professor at UCLA, recently discovered that Mars has tectonic plates similar to those that we have on Earth. Yin made this discovery when he observed that the sides of the 2,500-mile-long Martian canyon, Valles Marineris, had moved roughly 93 miles relative to each other. Make the jump to find out just how he did it and what it means for us on Earth.