Last updated on April 17, 2014 at 1:21 EDT
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July 31, 2012
This image shows a lava flow that has filled in a neighboring crater (top right), leaving only a trace of the covered crater rim at the surface. These filled craters are referred to as ghost craters. The lines seen forming a network of cracks across the surface are called troughs. Troughs formed as the lava flow cooled, and the surface was cracked and faulted. This image was acquired as part of MDIS's high-resolution 3-color imaging campaign. The 3-color campaign is a major mapping activity in MESSENGER's extended mission. It complements the 8-color base map (at an average resolution of 1 km/pixel) acquired during MESSENGER's primary mission by imaging Mercury's surface in a subset of the color filters at the highest resolution possible. The three narrow-band color filters are centered at wavelengths of 430 nm, 750 nm, and 1000 nm, and image resolutions generally range from 100 to 400 meters/pixel in the northern hemisphere. 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, MESSENGER acquired 88,746 images and extensive other data sets. MESSENGER is now in a yearlong extended mission, during which plans call for the acquisition of more than 80,000 additional images to support MESSENGER's science goals. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington