Good Things Come in Small Packages: Nasa Messenger Image - Release Date 13 Oct 2011

Date acquired: September 17, 2011 Image Mission Elapsed Time (MET): 224720885 Image ID: 769834 Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS) WAC filter: 10 (898 nanometers) Center Latitude: 73.33° Center Longitude: 68.82° E Resolution: 341 meters/pixel Scale: The distance from the central peak to the crater rim is about 43 km (26.7 miles). Incidence Angle: 84.2° Emission Angle: 0.1° Phase Angle: 84.2° Of Interest: This image, taken with the Wide Angle Camera (WAC), shows an unnamed complex crater not far from Mercury's northern pole. Though small, the image still gives us an excellent view of many of the crater's features, including a central peak and its shadow, some smooth impact melt pools on the rim, secondary crater chains and clusters on the smooth floor, and an un-weathered ejecta blanket. The impact melt pools and texture of the eject blanket suggest that this is a relatively young crater. The small size of the image is due to binning, a data processing technique in which data volume is reduced by combining groups of pixels into a single pixel, reducing the overall number of pixels and thus reducing the size of the image data file that must be stored on the spacecraft and transmitted to Earth. This image was acquired as part of MDIS's color base map. The color base map is composed of WAC images taken through eight different narrow-band color filters and will cover more than 90% of Mercury's surface with an average resolution of 1 kilometer/pixel (0.6 miles/pixel). The highest-quality color images are obtained for Mercury's surface when both the spacecraft and the Sun are overhead, so these images typically are taken with viewing conditions of low incidence and emission angles.

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington