What a difference a week makes. Today's featured image was acquired earlier this month, one week after this image (PIA17579), showing how the lighting conditions change in an Earth week (but only about 4% of a Mercury day). Can you spot the crater with the prominent secondary chains? With the Sun now a bit higher above this crater (located about a quarter of the way up from the bottom of the frame), its floor appears smooth, and its crater chains can still be seen to stretch far from its rim.

This image was acquired as part of MDIS's limb imaging campaign. Once per week, MDIS captures images of Mercury's limb, with an emphasis on imaging the southern hemisphere limb. These limb images provide information about Mercury's shape and complement measurements of topography made by the Mercury Laser Altimeter (MLA) of Mercury's northern hemisphere.

Date acquired: October 09, 2013
Image Mission Elapsed Time (MET): 23629938
Image ID: 4974132
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: -43.49°
Center Longitude: 150.4° E
Resolution: 1085 meters/pixel
Incidence Angle: 77.7°
Emission Angle: 57.7°
Phase Angle: 132.9°

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.