After reaching orbit around Mercury on March 17, NASA's MESSENGER spacecraft has sent back its first image of our solar system's innermost planet. The historic image, which was captured at 5:20 am EDT (U.S.), is the first ever captured from a spacecraft in orbit and is dominated by the rayed crater named Debussy. The bottom portion of the image also shows a region of Mercury's surface near the planet's south pole that had not previously been seen by spacecraft.
During the six hours following the snapping of the first image, MESSENGER acquired an additional 363 images before downlinking some of the data to Earth, where the MESSENGER team continues to examine it. Over the next three days, MESSENGER will acquire an additional 1,185 images to verify the performance of the spacecraft's Mercury Dual Imaging System (MDIS), which consists of a pair of color cameras – one a narrow angle imager and a the other wide angle imager – that will take pictures of Mercury in visible and near-infrared light.
MESSENGER's year-long primary mission, which will begin on April 4, will see the MDIS acquire more than 75,000 images to support the mission goals of unraveling the history and evolution of the planet. To this end MESSENGER also carries seven scientific instruments and a radio science experiment that together are designed to gather data on the composition and structure of Mercury's crust, its geologic history, the nature of its magnetosphere and thin atmosphere, and the makeup of its core and the materials near its poles.
NASA will be releasing further images captured by MESSENGER over the coming days, which will be available at the MESSENGER web site.