The top image is a MASCS VIRS color composite of Waters crater (center) in Mercury's mid latitudes. The bottom image is a monochrome MDIS mosaic of the same area. The central blue area corresponds to both Waters and its impact melt flow. The encompassing yellow area likely relates to Waters' ejecta blanket. Blue areas indicate low reflectance, while yellow areas relate to high reflectance and newer material.
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. In the MDIS mosaic, some brightness variations are due to tiling of images taken at different illuminations.
Date Created: July 7, 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 Latitude: -9.1°
Center Longitude: 254.6° E
Resolution: 0.5 km/pixel
Scale: Waters crater (center) is about 15 km (9.3 mi.) in diameter.
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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