Data Set Overview : The THEMIS IR-EDR data set contains the raw thermal infrared observations and their associated calibration images. Each qube header includes basic parameters describing the observation and various telemetry information associated with the observation.  The IR-EDR data set is one of several associated data sets included on the Mars Odyssey THEMIS Standard Products volume. These data sets include the experimental, reduced, and derived data products. Each observation in the experimental (EDR) and reduced (RDR) data sets is stored in a single PDS SPECTRAL_QUBE image product, while each observation in the derived (BTR or ABR) data sets is stored in a single PDS IMAGE product.  This data set may be reprocessed at the end of the Odyssey mission.   Data : The THEMIS instrument is a combined thermal infrared (IR) and visible (VIS) multispectral, pushbroom imager. The IR and VIS detector arrays are co-aligned, allowing, if desired, the simultaneous observation of the same Mars surface location with each detector.  Each image may contain any combination of the available wavelength bands: there are ten available bands in the IR detector array, and there are five available bands in the VIS detector array. IR images are 320 pixels wide and vary in length from 272 to 65,296 pixels long. VIS images are acquired in framelets of size 1024 pixels wide by 192 pixels long; the number of framelets per image is determined by the number of bands selected, such that the total image size does not exceed 3.734 Mbytes. Spatial summing may be applied after image collection, thereby reducing the nominal image dimensions listed above.  All images follow PDS formatting standards and are stored as binary images with attached ASCII label and header data objects. The label of THEMIS SPECTRAL_QUBE data products (EDRs and RDRs) contains identification and observation parameters associated with the image. Also in each header is a HISTORY data object, in ASCII format, detailing all processing applied during the generation of the product. For raw infrared (IR EDR) products, the header also includes a second data object containing binary telemetry information that was sampled regularly throughout the observation.  The application of the THEMIS calibration algorithms transforms a raw (EDR) image into a radiometrically calibrated (RDR) image with only minor changes to the file format. Then, the THEMIS derived products are calculated from a single band of the corresponding RDR: the infrared brightness temperature records (IR BTR) are usually derived from band 9 (12.57 um); the visible apparent brightness records (VIS ABR) are usually derived from band 3 (0.654 um). The results are stored as an 8-bit IMAGE with an attached label containing identification and some basic geometric parameters. For more details of the THEMIS processing algorithms and the data product formats, please refer to the Mars Odyssey THEMIS: Data Processing User's Guide (CHRISTENSEN2009) and the Mars Odyssey THEMIS: Standard Data Products SIS (CHRISTENSEN2014a), included with this data set archive.   Coordinate System : The data products included on the Mars Odyssesy THEMIS Standard Products volume are not projected into any coordinate systems. The image files maintain the raw raster order produced by the instrument, reorganized to group together the data from each band. The SPECTRAL_QUBE band are not spatially registered. Layers within a single product can be out of registration with each other by up to 10 lines and/or columns.  The geometric parameters stored in the headers of the BTR and ABR IMAGE products are generated using the appropriate Odyssey SPICE kernels and a THEMIS specific model in the ISIS software. The values provided represent the center of the image and are based on the Mars IAU 2000 aerocentric model with east positive longitude.   Software : All data products on this volume follow the PDS standards appropriate for the data type, SPECTRAL_QUBE or IMAGE. Any software tool that understands that structure should be able to open and manipulate them.  The THEMIS team uses the software tools DAVINCI and ISIS to display, analyze, and project the data products. DAVINCI is a data analysis package for working with multi-spectral images; it is distributed by the ASU Mars Space Flight Facility and is available at http://davinci.asu.edu. ISIS is an image processing package produced by USGS-Flagstaff and available at http://isis.astrogeology.usgs.gov.   Media/Format : The publication and distribution of this data set will be facilitated online through the THEMIS Data Node (http://static.mars.asu.edu/pds). Due to the large volume of data products expected from the mission, physical copies of the data will be made for PDS long-term archive purposes only.

Please refer to the Mars Odyssey Processing User's Guide (CHRISTENSEN2009), which is included with this data set archive.