| Date acquired: September 07, 2011 Image Mission Elapsed Time (MET): 223922395 Image ID: 730933 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: -57.84° Center Longitude: 329.6° E Resolution: 193 meters/pixel Scale: Hesiod crater is about 100 km (62 miles) in diameter Incidence Angle: 62.7° Emission Angle: 21.7° Phase Angle: 84.5° Of Interest: The crater at the western corner of this image is Hesiod. The northern and eastern parts of Hesiod's rim are marked by irregular depressions. These depressions are thought to be vents from which explosive (pyroclastic) volcanic eruptions originated. The high-reflectance areas on the wall of the crater just to the northeast of Hesiod and at the top of the image share color characteristics with other pyroclastic deposits known on Mercury. Pyroclastic eruptions are driven by volatile compounds, and MESSENGER has revealed that Mercury has a higher abundance of volatile elements than was previously expected. This image was acquired as part of MDIS's high-resolution surface morphology base map. The surface morphology base map will cover more than 90% of Mercury's surface with an average resolution of 250 meters/pixel (0.16 miles/pixel or 820 feet/pixel). Images acquired for the surface morphology base map typically have off-vertical Sun angles (i.e., high incidence angles) and visible shadows so as to reveal clearly the topographic form of geologic features. | |
| Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
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