The left column of images shows MASCS VIRS interpolated color composites of Kertesz (top), Dominici (middle), and an unnamed crater (bottom). The middle column shows the VIRS color composite of spectral footprints, and the left column shows monochrome MDIS images for the same areas. Yellow areas are highly reflective and thought to be relatively young, exhibiting fewer effects of space weathering. Kertesz and Dominici are also known to contain hollows, which are shallow depressions with younger surfaces likely caused by the loss of volatiles.
The VIRS composite shows hundreds of individual footprints tracks (minimum 100-200 m across and 3-4 km long) taken from different directions and altitudes. In locations where multiple footprints cover the same area, the footprint with the best illumination for mineralogical interpretation (usually the lowest incidence angle where shadows are minimized) is used for making the map. Where footprints are sparse, interpolation is required for full spatial coverage.
Date Created: July 28, 2014
Instruments: Visible and Infrared Spectrograph (VIRS) of the Mercury Atmosphere and Surface Composition Spectrometer (MASCS) and Mercury Dual Imaging System (MDIS)
VIRS Color Composite Wavelengths: 575 nm as red, 415 nm/750 nm as green, 310 nm/390 nm as blue
Center Latitudes: 27.3° (top); 1.18° (middle); -3.6° (bottom)
Center Longitudes: 146.1° E (top); 323.5° E (middle); 60.9° E (bottom)
Resolution: 0.5 km/pixel
Scale: Kertesz crater (top) has a diameter of 32 km (20 mi.); Dominici crater (middle) has a diameter of 20 km (12 mi.)
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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