This image, taken with the Wide Angle Camera (WAC), shows Rachmaninoff, a double-ring basin named in March 2010 for the Russian composer, pianist and conductor Sergei Rachmaninoff (1873-1943). Rachmaninoff was first imaged in its entirety during MESSENGER's third Mercury flyby. Of particular interest to geologists are the troughs, or "graben," on the basin floor, which are thought to have formed as the central smooth, volcanic plains cooled or possibly as other tectonic forces pulled the crust apart.

This image was acquired as part of MDIS's high-resolution surface morphology base map. The surface morphology base map will cover more than 90% of Mercury's surface with an average resolution of 250 meters/pixel (0.16 miles/pixel or 820 feet/pixel). Images acquired for the surface morphology base map typically have off-vertical Sun angles (i.e., high incidence angles) and visible shadows so as to reveal clearly the topographic form of geologic features.

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. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MDIS is scheduled to acquire more than 75,000 images in support of MESSENGER's science goals.

Date acquired: September 15, 2011
Image Mission Elapsed Time (MET): 224592808
Image ID: 763457
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 26.22°
Center Longitude: 58.39° E
Resolution: 350 meters/pixel
Scale: Rachmaninoff basin is 290 kilometers (180 miles) in diameter
Incidence Angle: 61.8°
Emission Angle: 0.1°
Phase Angle: 61.9°

These images are from MESSENGER, a NASA Discovery mission to conduct the first orbital study of the innermost planet, Mercury. For information regarding the use of images, see the MESSENGER image use policy.