The MESSENGER spacecraft took this image on the surface of Mercury a couple of years ago. MESSENGER has already taken 150,000 pictures, and will continue snapping them until 2015. So it's no wonder that it took NASA this long to analyze enough data to determine that Han Solo has been photographed. Here's part of NASA's statement on the find:
If there are two things you should remember, it's not to cross a Hutt, and that Mercury's surface can throw up all kinds of surprises. In this image, a portion of the terrain surrounding the northern margin of the Caloris basin hosts an elevated block in the shape of a certain carbonite-encased smuggler who can make the Kessel Run in less than twelve parsecs.
(Image credit:NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)