The plains that surround the Caloris basin are geologically complex. Today's featured images highlights some of the kilometer-scale knobs that surround much of the basin, which are thought to be blocks of material ejected by the Caloris basin-forming event. This area, a region within Tir Planitia, has also been subjected to compressional stresses, which resulted in the formation of scarps that cut across the scene. Unraveling the complex sequence of events in this region, which includes deposition of ejecta, possible volcanic resurfacing, and tectonic deformation, will be aided by the high-resolution targeted images to be collected in MESSENGER's second extended mission.

This image was acquired as a targeted set of stereo images. Targeted stereo observations are acquired at resolutions much higher than that of the 200-meter/pixel stereo base map. These targets acquired with the NAC enable the detailed topography of Mercury's surface to be determined for a local area of interest.

Date acquired: April 05, 2013
Image Mission Elapsed Time (MET): 7472448
Image ID: 3825184
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 4.31°
Center Longitude: 185.6° E
Resolution: 61 meters/pixel
Scale: This scene is approximately 80 km (50 mi.) across
Incidence Angle: 73.6°
Emission Angle: 40.8°
Phase Angle: 114.1°

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. MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015.

For information regarding the use of images, see the MESSENGER image use policy.