The Law of Superposition provides MESSENGER team scientists with the means to determine the order in which features were formed on the surface of Mercury. In this image, where north is to the top, several superposed landforms paint a complex story. The oldest feature is a near-circular crater that almost spans the entire field of view, and which is barely visible today. Later, at least three more craters were formed (one on the left, and two smaller examples on the right), before smooth plains filled all four craters. Later, a large lobate scarp cut north-south through the original crater. Later still, a simple crater formed right along the scarp -- and so this crater is the youngest of those features described here. Observations like these can be used to help understand the developmental history of the innermost planet.

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.

Date acquired: July 17, 2012
Image Mission Elapsed Time (MET): 251000122
Image ID: 2215546
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -29.66°
Center Longitude: 143.49° E
Resolution: 92 meters/pixel
Scale: The field of view in this image is approx. 98 km (61 mi.) across
Incidence Angle: 73.3°
Emission Angle: 23.2°
Phase Angle: 96.4°

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. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MDIS acquired 88,746 images and extensive other data sets. MESSENGER is now in a year-long extended mission, during which plans call for the acquisition of more than 80,000 additional images to support MESSENGER's science goals.

These images are from MESSENGER, a NASA Discovery mission to conduct the first orbital study of the innermost planet, Mercury. For information regarding the use of images, see the MESSENGER image use policy.