Unmasking the secrets of Mercury, in color

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. MESSENGER's highly successful orbital mission is about to come to an end, as the spacecraft runs out of propellant and the force of solar gravity causes it to impact the surface of Mercury near the end of April 2015.