This image taken by MDIS's Wide Angle Camera is dominated by an unnamed basin formed from a large impact on the surface of Mercury. Although the impact was energetic enough to create a central peak ring in the basin, the ring has been mostly flooded by impact melt and/or volcanic plains. To the MESSENGER summer interns, the partial ring of mountains resembles a smile.

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: July 16, 2011
Image Mission Elapsed Time (MET): 219266241
Image ID: 509587
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 51.79°
Center Longitude: 82.82° E
Resolution: 203 meters/pixel
Scale: The basin is approximately 180 km (112 mi) in diameter
Incidence Angle: 62.3°
Emission Angle: 0.2°
Phase Angle: 62.5°

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.