This crater is now called Rustaveli.  The original NASA caption follows.<br><p>Date acquired: July 16, 2011<br>
Image Mission Elapsed Time (MET): 219266241<br>
Image ID: 509587<br>
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)<br>
WAC filter: 7 (748 nanometers)<br>
Center Latitude: 51.79°<br>
Center Longitude: 82.82° E<br>
Resolution: 203 meters/pixel<br>
Scale: The basin is approximately 180 km (112 mi) in diameter<br>
Incidence Angle: 62.3°<br>
Emission Angle: 0.2°<br>
Phase Angle: 62.5°<br></p><p>Of Interest: This image taken by MDIS's Wide Angle Camera is dominated by an unnamed basin formed from a large impact on the surface of Mercury. Although the impact was energetic enough to create a central peak ring in the basin, the ring has been mostly flooded by impact melt and/or volcanic plains. To the MESSENGER summer interns, the partial ring of mountains resembles a smile.
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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.
NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
<a rel="nofollow" class="external text" href="https://messenger.jhuapl.edu/Explore/Science-Images-Database/gallery-image-598.html">MERCURY'S SMILE</a>