PIA15345: Ribbons and Chains

Ribbons and Chains


This view shows several groups of similar-sized craters arranged roughly in lines. Crater chains are sometimes formed by volcanic eruptions, but the craters here were made by secondary impacts. The excavation of a large crater or basin can throw out blocks of material along radial trajectories. The blocks then sometimes strike the surface nearly in the same location, producing secondary crater chains. Finer ejecta may form the bright ribbons known as crater rays .

This image was acquired as part of MDIS's high-resolution surface morphology base map. The surface morphology base map covers more than 90% of Mercury's surface with an average resolution of 250 meters/pixel (0.16 miles/pixel or 820 feet/pixel). Images acquired for the surface morphology base map typically have off-vertical Sun angles (i.e., high incidence angles) and visible shadows so as to reveal clearly the topographic form of geologic features.

Date acquired: June 07, 2011
Image Mission Elapsed Time (MET): 215937760
Image ID: 349758
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 35.48°
Center Longitude: 123.4° E
Resolution: 236 meters/pixel
Scale: The edges of the image are about 120 km (75 mi.) long.
Incidence Angle: 63.0°
Emission Angle: 11.7°
Phase Angle: 51.3°

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 is scheduled to acquire more than 75,000 images in support of 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
Target Type Planet
Instrument Host MESSENGER
Host Type Orbiter
Instrument Mercury Dual Imaging System (MDIS)
Detector Wide Angle Camera (WAC)
Extra Keywords Crater, Grayscale, Impact, Map, Radio, Shadow, Volcano
Acquisition Date
Release Date 2012-01-25
Date in Caption 2011-06-07
Image Credit NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Source photojournal.jpl.nasa.gov/catalog/PIA15345
Identifier PIA15345