Today's image features an unnamed crater 35 km (~22 mi.) in diameter that is cross-cut by a lobate scarp. Superposition relations such as these provide scientists with strong evidence that the surface of Mercury has been extensively shortened, likely in response to the cooling and contraction of the planet's interior through time. Additionally, the change in shape of a once-circular crater cut by a scarp provides a way to estimate the amount of horizontal shortening across that scarp. Such relations, therefore, offer an import insight into the broader geological development of Mercury!
This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.
Date acquired: August 13, 2013
Image Mission Elapsed Time (MET): 18677753
Image ID: 4621861
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -7.05°
Center Longitude: 70.65° E
Resolution: 63 meters/pixel
Scale: The field of view in this image is approx. 80 km (50 mi.) across
Incidence Angle: 70.4°
Emission Angle: 32.8°
Phase Angle: 103.2°
North is up in this image.
Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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