The Pit Within: Nasa Messenger Mission Image: Release Date 27 Sept 2011

Date acquired: April 23, 2011 Image Mission Elapsed Time (MET): 212066694 Image ID: 167488 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 9.28° Center Longitude: 221.4° E Resolution: 197 meters/pixel Scale: The large flat-floored impact crater is about 70 km (44 mi.) in diameter. Incidence Angle: 67.9° Emission Angle: 10.1° Phase Angle: 57.7° Of Interest: This image shows a pit-floor crater , that is, an impact crater with a rimless depression in its floor. The pit is about 15 km long. The pit may have formed from volcanic activity, either as an eruptive vent or by collapse into a void formed when sub-surface magma withdrew. MESSENGER has found abundant evidence for volcanism on Mercury .

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