Last updated on April 17, 2014 at 7:54 EDT
Silky Smooth
215 of 1081

Silky Smooth

March 26, 2013
Release Date: March 21, 2013 Topics: NAC, Smooth Terrain, Volcanism Date acquired: February 13, 2013 Image Mission Elapsed Time (MET): 3843866 Image ID: 3567175 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 36.1° Center Longitude: 63.8° E Resolution: 26 meters/pixel Scale: The field of view in this image is approximately 25 km (16 mi.) across Incidence Angle: 68.6° Emission Angle: 11.9° Phase Angle: 80.4° (North is up in this image.) Of Interest: We have seen this distinctive, irregular depression before — in 2009 and again last year — but never at this resolution! The depression differs considerably from impact craters (it has no raised rim and an outline that is far from circular), and is surrounded by a smooth, velvety texture. Interpreted by scientists as a volcanic vent, the smooth texture is actually a blanket of very fine particles of lava that were ejected explosively from the vent in a pyroclastic eruption. Striations in the walls of the vent are visible in this image, as are very small impact craters that post-date the vent's formation. 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. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. During the first two years of orbital operations, MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington