PIA16544: Sousa's Shadow


Sousa’s Shadow

Caption:

This image, taken with the Wide Angle Camera (WAC), gives us a close-up look at Sousa crater. Named for the American bandmaster and composer John Philip Sousa, Sousa crater was one 23 craters named in April 2012 by the IAU. The shadows cast by the Sun, which is located near the horizon, emphasize Sousa's peak ring and ejecta blanket. With the exception of a few crater chains and some small craters, Sousa's floor is smooth, likely a result of being flooded with lava .

This image was acquired as part of MDIS's high-incidence-angle base map. The high-incidence-angle base map is a major mapping activity in MESSENGER's extended mission and complements the surface morphology base map of MESSENGER's primary mission that was acquired under generally more moderate incidence angles. High incidence angles, achieved when the Sun is near the horizon, result in long shadows that accentuate the small-scale topography of geologic features. The high-incidence-angle base map is being acquired with an average resolution of 200 meters/pixel.

Date acquired: October 06, 2012
Image Mission Elapsed Time (MET): 258054892
Image ID: 2717245
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 46.57°
Center Longitude: 359.7° E
Resolution: 246 meters/pixel
Scale: Sousa crater is 120 km (75 miles) in diameter
Incidence Angle: 86.9°
Emission Angle: 24.2°
Phase Angle: 111.2°

Background Info:

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 .

Cataloging Keywords:

Name Value Additional Values
Target Mercury
System
Target Type Planet
Mission MESSENGER
Instrument Host MESSENGER
Host Type Orbiter
Instrument Mercury Dual Imaging System (MDIS)
Detector Wide Angle Camera (WAC)
Extra Keywords Crater, Grayscale, Map, Radio, Shadow
Acquisition Date
Release Date 2012-11-20
Date in Caption 2012-10-06
Image Credit NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Source photojournal.jpl.nasa.gov/catalog/PIA16544
Identifier PIA16544