PIA18951: Permanent Darkness

Permanent Darkness


Located near Mercury's north pole , inside this unnamed crater there are locations that are in permanent darkness. Mercury's axial tilt is nearly zero, so the tall crater walls cast shadows that the Sun never pierces. There is evidence that this crater contains ice within its permanently shadowed interior.

This image was acquired as part of MDIS's high-resolution 3-color imaging campaign. The map produced from this campaign complements the 8-color base map (at an average resolution of 1 km/pixel) acquired during MESSENGER's primary mission by imaging Mercury's surface in a subset of the color filters at the highest resolution possible. The three narrow-band color filters are centered at wavelengths of 430 nm, 750 nm, and 1000 nm, and image resolutions generally range from 100 to 400 meters/pixel in the northern hemisphere.

Date acquired: July 30, 2012
Image Mission Elapsed Time (MET): 252149342
Image ID: 2297378
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 84.08°
Center Longitude: 29.16° E
Resolution: 69 meters/pixel
Scale: This crater has a diameter of 24 kilometers (15 miles)
Incidence Angle: 84.1°
Emission Angle: 18.9°
Phase Angle: 84.3°

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. During the first two years of orbital operations, MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015.

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, Map, Radio, Shadow
Acquisition Date
Release Date 2014-11-17
Date in Caption 2012-07-30
Image Credit NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Source photojournal.jpl.nasa.gov/catalog/PIA18951
Identifier PIA18951