The smallest planet in the solar system keeps serving up big surprises. Scientists working on the NASA MESSENGER MISSION to MERCURY have found that the planet has unexpected inner layers and craters with tilted bottoms, and it may have been geologically active far later into its life than previously imagined. The spacecraft entered orbit around Mercury March 17, 2012. Already planetary scientists have DISCOVERED WHAT APPEARS TO BE WATER ICE on the hottest planet at its polar dark craters - similar to the Moon.
Credit: outer-space-guests.blogspot.com