rivin2e writes "It would seem our neighbor, the moon, has something hidden below the surface. 'Images collected by the Lunar Reconnaissance Orbiter hints the moon has probably seen tectonic activity within the last 50 million years.' It would appear from the article that the moon is changing a lot more than we think, even if it doesn't seem like it. I, for one, am still waiting for that big black obelisk to be dug up." From NASA's press release: "A team of researchers analyzing high-resolution images obtained by the Lunar Reconnaissance Orbiter Camera (LROC) show small, narrow trenches typically much longer than they are wide. This indicates the lunar crust is being pulled apart at these locations. These linear valleys, known as graben, form when the moon's crust stretches, breaks and drops down along two bounding faults. A handful of these graben systems have been found across the lunar surface."