PIA15587: The High-Incidence Campaign

The High-Incidence Campaign


Acquiring high-incidence-angle images of Mercury's surface is a major mapping activity in MESSENGER's extended mission. The high-incidence campaign compliments the surface morphology base map of MESSENGER's primary mission, which 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.

This image is part of the high-incidence campaign and shows part of Jokai crater, a 93 km (58 mi.) diameter complex crater named for the 19th century Hungarian novelist Mor Jokai. Two smaller craters overprint the rim of Jokai. Jokai itself overprinted a similarly-sized crater, and part of the remaining older crater's wall can be seen towards the left side of this image.

Date acquired: April 11, 2012
Image Mission Elapsed Time (MET): 242631251
Image ID: 1633957
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 71.3°
Center Longitude: 224.0° E
Resolution: 173 meters/pixel
Scale: The small, shadowed crater at the center of the image is approximately 14 km (8.7 mi.) in diameter.
Incidence Angle: 80.4°
Emission Angle: 11.2°
Phase Angle: 69.1°

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 Sun
System Mercury
Target Type Planet Sun
Instrument Host MESSENGER
Host Type Orbiter
Instrument Mercury Dual Imaging System (MDIS)
Extra Keywords Crater, Grayscale, Map, Radio, Shadow
Acquisition Date
Release Date 2012-04-16
Date in Caption 2012-04-11
Image Credit NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Source photojournal.jpl.nasa.gov/catalog/PIA15587
Identifier PIA15587