This image, captured by the Narrow Angle Camera (NAC), shows a number of trails of small craters. These trails, called secondary crater chains, are formed when ejecta from an initial impact are launched outward. As the ejecta fall back onto the planet's surface, they can form their own, often overlapping, small craters.

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: August 20, 2011
Image Mission Elapsed Time (MET): 222325515
Image ID: 654912
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -73.33°
Center Longitude: 59.77° E
Resolution: 220 meters/pixel
Scale: From left corner to right corner, this image is approximately 320 km (200 miles) across
Incidence Angle: 78.2°
Emission Angle: 0.8°
Phase Angle: 78.8°

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.