Today's featured image highlights the first set of color images from a new imaging campaign: minimum-phase-angle color. Near the north polar region, the incidence angle (measured from the vertical) is always high because the Sun is low on the horizon. The minimum-phase-angle color campaign acquires images from as close to the direction of solar illumination as possible, which minimizes the phase angle and thus the shadows in a given area. Images are acquired through five of the WAC's narrow-band color filters, for regions north of 60° N, at an average resolution of 500 meters/pixel.
With this imaging campaign, the MESSENGER team will be searching for spectral differences among Mercury's northern smooth plains and the ejecta of craters that could indicate compositional differences. In today's image you can see a portion of Botticelli crater, which does not appear to have a strong color contrast from its surroundings.
Date acquired: March 21, 2013
Image Mission Elapsed Time (MET): 6148727, 6148718, and 6148724
Image ID: 3731063, 3731060, 3731062
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: 62.14°
Center Longitude: 248.1° E
Resolution: 316 meters/pixel
Scale: Botticelli crater is approximately 120 km (75 mi.) across
Incidence Angle: 77.3°
Emission Angle: 49.2°
Phase Angle: 28.0°
North is up in this image.
Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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