Today's image shows an area in Mercury's northern latitudes crossed by a series of MASCS VIRS tracks displayed as a color composite, overlain on a MDIS base map mosaic. Craters Verdi and Janáček reside in this area, along with several unnamed craters. The VIRS footprints are smaller, each covering less area, in the northern hemisphere due to MESSENGER's elliptical orbit.
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 27, 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: 57.7°
Center Longitude: 197.5° E
Resolution: 1 km/pixel
Scale: Verdi (top left) crater is 145 km (90 miles) in diameter
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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