This high-resolution NAC image gives us another glimpse at Ailey , one of the 23 Mercury craters named in April 2012 . The area surrounding these craters, the continuous ejecta blanket , is very smooth. A continuous ejecta blanket is the area immediately surrounding an impact that is entirely covered by debris from the collision. In Ailey's case, the ejecta blanket appears smooth because any roughness in the previously existing terrain was filled in by the pulverized falling debris. This scene includes a crater that was partially buried by Ailey's impact, making it faintly resemble Ms. Pacman.
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.
May 06, 2011
Image Mission Elapsed Time (MET): 213154766
Image ID: 218729
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 45.74°
Center Longitude: 178.0° E
Resolution: 40 meters/pixel
Scale: Ailey, the smaller crater that has partially buried the larger crater, has a diameter of approximately 21 km (13 miles).
Incidence Angle: 75.3°
Emission Angle: 36.8°
Phase Angle: 112.1°
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. 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 .
|Instrument||Mercury Dual Imaging System (MDIS)|
|Detector||Narrow Angle Camera (NAC)|
|Extra Keywords||Collision, Crater, Grayscale, Impact, Map, Radio|
|Date in Caption||2011-05-06|
|Image Credit||NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington|