Data from the second MESSENGER flyby of Mercury is coming in; NASA held a telephone press conference today to release some new, interesting stuff. Although scientifically it's just a tease, my favorite is this picture:
By eye, Mercury is a relatively uniform grey with splotches of variation in brightness. But MESSENGER's sensitive cameras have filters on them which isolate different colors, and when put together and enhanced they show subtle color changes on the planet's face. These colors are almost certainly due to changes in the composition of the rocks on the surface... in other words, MESSENGER can do mineralogical studies from space!
MESSENGER's colorized Mercury
In this closeup view, younger terrain on the left is yellower, while older features appear blue. We know the area on the left is young because it's smooth; it hasn't been around long enough to get bombarded from space by comet and asteroid impacts. On the right, the material that appears blue may have been ejected by the impact that formed the crater on the right. Remember, these colors are not nearly this striking to the eye! It's only because we can enhance MESSENGER's color information that these color features are visible. Sadly, the flyby was so fast that scientists can't really interpret these colors and tag them to different kinds of minerals. But MESSENGER is going to settle into orbit around Mercury in 2011, and once it does, these cameras will map the surface to their hearts' (well, CPUs') content, providing us with incredible details of the content of this dinky, battered, roasted planet. Image credit: NASA.