A Finished View
Before NASA's MESSENGER spacecraft left Earth, we only knew what about half of Mercury looked like. Now that the orbiter has flown around the innermost planet for two years with its Mercury Duel Imaging System instrument and taken more than 160,000 images, astronomers were able to announce last week that a full 100 percent of the planet has been mapped. Scientists will use this information -- and the even higher resolution images that MESSENGER continues to take -- to study how Mercury formed and evolved.
Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington