Taken as MESSENGER approached Mercury, this NAC image shows a portion of the sunlit crescent-shaped planet (see PIA11247) with the edge of Mercury against the blackness of space. A large region of smooth plains can be seen in the upper portion of this image, extending to the north, into an image previously released on October 8 (see PIA11353). To the south, near the edge of the planet, a lengthy cliff face is visible running off the bottom of the image and onto an image released on October 17 (see PIA11370). With this overlap, these three NAC images can be nicely mosaicked together and are part of a larger 44-image mosaic set. Particularly prominent in the image here is a crater near the bottom of the frame with numerous associated chains of small secondary craters. The secondary craters, which are especially visible on the southern portion of the smooth plains, were formed when material was thrown out onto the surrounding surface during the impact event that created the large crater. Thus, this large crater was formed after the creation of the neighboring smooth plains.

Date Acquired: October 6, 2008
Image Mission Elapsed Time (MET): 131766475
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Resolution: 420 meters/pixel (0.26 miles/pixel) at the right side of the image
Scale: The right side of this image is about 430 kilometers (270 miles) tall
Spacecraft Altitude: 16,400 kilometers (10,200 miles)

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.