Mosaicking of global planetary image datasets: 1. Techniques and data processing for Thermal Emission Imaging System (THEMIS) multi-spectral data

Abstract

[1] The mosaicking of global planetary data sets allows for the examination of local, regional, and global scale processes on all planetary bodies. Processing techniques that allow us and other users to crate mosaics of tens of thousands of images are documented along with the associated errors introduced by each image-processing algorithm. These techniques (e.g., non-uniformity correction, running contrast stretches, line and row correlated noise removal, and random noise removal) were originally developed for the 2001 Mars Odyssey Thermal Emission Imaging System (THEMIS) infrared multispectral imager data but can be adapted and applied to other data sets by the alteration of input parameters. The techniques for mosaicking planetary image data sets (e.g., image registration, blending, and normalization) are also presented along with the generation of qualitative and quantitative products. These techniques are then applied to generate THEMIS daytime and nighttime infrared, Viking, Context Imager (CTX), and Mars Orbiter Camera (MOC) visible mosaics using a variety of input and output types at a variety of scales. By creating mosaics of the same area using different data sets such as those that illustrate compositional diversity, thermophysical properties, or small-scale morphology, it is possible to view the surface of the planet and geologic problems through many different perspectives. In addition to the techniques used to create large-scale seamless mosaics, we also present the THEMIS daytime and nighttime relative temperature global mosaics, which are the highest resolution (100m/pixel) global scale data sets available for Mars to date.

Episodes of fluvial and volcanic activity in Mangala Valles, Mars

“…Digital mapping was performed using an image mosaic base layer consisting of daytime infrared images acquired from the Mars Odyssey Thermal Emission Imaging System (THEMIS) instrument (Christensen et al, 2004), with a spatial resolution of 100 m/pixel (Edwards et al, 2011;Hill et al, 2014). Individual CTX images were used for detailed mapping and analysis due to their relatively high resolution (~6 m/pixel), near-ideal illumination conditions (~3 PM), and excellent coverage of the mapping area.…”

Large impact crater histories of Mars: The effect of different model crater age techniques

“…THermal EMission Imaging Spectrometer (THE-MIS) data were utilized, specifically the daytime infrared (12.57 lm) global mosaic with 100 m spatial resolution (Christensen et al, 2004;Edwards et al, 2011). This dataset covers )99% of the surface of Mars and was also a basemap for identifying the craters in Robbins and Hynek (2012).…”

Physical abrasion of mafic minerals and basalt grains: Application to martian aeolian deposits

“…Brightness temperatures were derived from calibrated radiance images and corrected for instrumental effects using methods described in Christensen et al (2004), Bandfield et al (2004), and Edwards et al (2011). This study uses nighttime temperatures when thermal contrast due to particle size is at a maximum and to ensure that the effects of albedo and sun--lit slopes have largely dissipated (e.g., Kieffer et al, 1977;Palluconi and Kieffer, 1981;Christensen, 1982).…”

“…Latitude and longitude values are used to extract elevation (atmospheric pressure) and albedo values from the Mars Orbiter Laser Altimeter (Smith et al, 2001) and the Thermal Emission Spectrometer data maps, respectively. IR dust opacities were converted to visible wavelength dust opacities for use in the KRC model by scaling the IR opacities by a factor of 2, according to the visible/9--μm extinction opacity ratio (Clancy et al, 1995;Wolff and Clancy, 2003 (Edwards et al, 2011) for each dune field location included in this study.…”