NASA uncovered more details of the first rock from the sun aka Mercury from its orbiting space laboratory called Messenger. Messenger has been sending tens of thousands of high detail images of the planet's surface from orbit for the past three months. Here are some of the findings. For more, read Larry Dignan's post on SmartPlanet.
Here, the crater Degas shows impact melt which coats its floor, and as the melt cooled and shrank, it formed the cracks observed across the crater. .
Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington