Hemingway (Merkurkrater)

Mercury global map 2013-05-14 bright.png
At the very end of 2012, MESSENGER obtained the final image needed to view 100% of Mercury's surface under daylight conditions. The mosaics shown here cover all of Mercury's surface and were produced by using the monochrome mosaic released by NASA's Planetary Data System (PDS) on March 8, 2013, as the base. The full resolution mosaics are available for download on MESSENGER's Global Mosaics webpage.

To fill the area near the north pole, the PDS product was trimmed northward of 83°N and an average mosaic that extended from 82.5°N to 90°N was used, averaging the 0.5° latitude overlap between the PDS mosaic and the average north polar mosaic. To fill the area near the south pole, the PDS product was trimmed southward of 85.5°S and an average mosaic that extended from 85°S to 90°S was used, again averaging the 0.5° latitude overlap. Any remaining gaps in the global mosaic were filled by using images obtained in support of the high-incidence imaging campaign.

This image is a brightness-corrected version of the original (Mercury - complete mono basemap 2500mpp equirectangular.png). Brightness levels were tuned from [0 - 255] to [30 - 180] for increase of contrast.

Hemingway crater.png
Image Mission Elapsed Time (MET): 131771988

Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Resolution: 260 meters/pixel (0.16 miles/pixel) Scale: This image is about 270 kilometers (170 miles) across Spacecraft Altitude: 10,100 kilometers (6,300 miles)

Of Interest: The crater Hemingway in the lower right-hand corner of this image has a patch of very dark material located near its center. The region of this image has been seen only with the Sun high overhead in the sky. Such lighting conditions are good for recognizing color differences of rocks but not well suited for ascertaining the topography of surface features from shadows. The shape of the surface in this area is difficult to resolve given the lighting angle, but the dark patch is not in shadow. Dark surfaces have also been seen on other regions of Mercury, including this dark halo imaged during the second Mercury flyby and near such named craters as Nawahi, Atget, and Basho seen during MESSENGER's first Mercury encounter. The example here is particularly striking, however, and from this NAC image the material may appear even darker than in other example areas. The dark color is likely due to rocks that have a different mineralogical composition from that of the surrounding surface. Understanding why these patches of dark rocks are found on Mercury's surface is a question of interest to the MESSENGER Science Team. The right edge of the image here aligns with this previously released NAC image, where other dark surface material, as well as patches of light-colored rocks, can be seen.