Date acquired: May 03, 2011
Image Mission Elapsed Time (MET): 212948404
Image ID: 208567
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -67.10°
Center Longitude: 254.8° E
Resolution: 295 meters/pixel
Scale: The Bach basin is 225 km (140 miles) across.
Incidence Angle: 67.0°
Emission Angle: 36.1°
Phase Angle: 103.1°

Of Interest: This image, taken with the MDIS Narrow Angle Camera (NAC), shows two named craters imaged by both MESSENGER and Mariner 10. At the bottom of the image are the double rings of Bach, a peak-ring basin named for the German composer J.S. Bach. The bright crater toward the top is Alencar, named for the Brazilian novelist José de Alencar; the central peak structure and terraced walls make it a good example of a complex crater.

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.

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

For information regarding the use of MESSENGER images, see the image use policy.