The very smooth region shown in this image is a part of Mercury's vast northern plains. These smooth plains are thought to have originated as volcanic outflows, in a similar manner to those within the Caloris basin. If you look closely, you can see several impact craters that were buried beneath the lava. These craters are known as "ghost craters" because only faint outlines of their rims remain.
This image was acquired as part of MDIS's high-resolution 3-color imaging campaign. The map produced from this campaign complements the 8-color base map (at an average resolution of 1 km/pixel) acquired during MESSENGER's primary mission by imaging Mercury's surface in a subset of the color filters at the highest resolution possible. The three narrow-band color filters are centered at wavelengths of 430 nm, 750 nm, and 1000 nm, and image resolutions generally range from 100 to 400 meters/pixel in the northern hemisphere.
Date acquired: September 03, 2012
Image Mission Elapsed Time (MET): 255173296, 255173291, 255173293
Image ID: 2512514, 2512512, 2512513
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: 51.83°
Center Longitude: 46.39° E
Resolution: 279 meters/pixel
Scale: 188 km (117 mi)
Incidence Angle: 65.2°
Emission Angle: 0.2°
Phase Angle: 65.4°
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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