This WAC image features a long, curving scarp (cliff) or rupes on Mercury . Based on the law of superposition we know that the crater formed before the scarp; the scarp bisects or "cuts" the edge of the crater. Scarps such as this one formed as the planet's interior cooled and contracted. The stresses caused by the shrinkage caused the crust to fracture, and the section of crust to the east (right) was pushed over the section to the west (left), greatly deforming the 23 km-diameter crater.
This image was acquired as part of MDIS's high-resolution surface morphology base map. The surface morphology base map covers more than 99% of Mercury's surface with an average resolution of 200 meters/pixel. Images acquired for the surface morphology base map typically are obtained at off-vertical Sun angles (i.e., high incidence angles) and have visible shadows so as to reveal clearly the topographic form of geologic features.
May 07, 2011
Image Mission Elapsed Time (MET): 213286335
Image ID: 224856
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 57.91°
Center Longitude: 307.2° E
Resolution: 125 meters/pixel
Scale: The crater is about 23 km (14 miles) in diameter.
Incidence Angle: 77.3°
Emission Angle: 4.5°
Phase Angle: 81.8°
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 acquired 88,746 images and extensive other data sets. MESSENGER is now in a year-long extended mission, during which plans call for the acquisition of more than 80,000 additional images to support MESSENGER's science goals.
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 .
|Instrument||Mercury Dual Imaging System (MDIS)|
|Detector||Wide Angle Camera (WAC)|
|Extra Keywords||Crater, Grayscale, Map, Radio, Shadow|
|Date in Caption||2011-05-07|
|Image Credit||NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington|