Instrument: X-Ray Spectrometer (XRS) and Gamma-Ray Spectrometer (GRS)Of Interest: Maps of magnesium/silicon (left) and thermal neutron absorption (right) across Mercury’s surface (red indicates high values, blue low) are shown. These maps, together with maps of other elemental abundances, reveal the presence of distinct geochemical terranes. Volcanic smooth plains deposits are outlined in white. Read the mission news story to learn more! The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft’s seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System’s innermost planet. In the mission’s more than three years of orbital operations, MESSENGER has acquired over 250,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington