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ABR Apparent Brightness Record - The ABR is derived from band 3 of a VIS-RDR QUBE (or first available band of the highest calibration product available). See sdpsis.pdf for a summary of the image processing. This file is a PDS IMAGE object with an attached PDS label. Bands Band numbers correspond to each layer contained in an image; up to 10 bands available in an IR image, and up to 5 bands available in a VIS image. The band number is equivalent to the instrument band number listed in Table 1, Section 2.2 of the THEMIS sdpsis.pdf. BTR Brightness Temperature Record - The BTR is derived from band 9 of a IR-RDR QUBE (or first available band of the highest calibration product available). See sdpsis.pdf for a summary of the image processing. This file is a PDS IMAGE object with an attached PDS label. Calibration Flag Flag indcates potential problems may have been encountered during the IR calibration routine; the user is advised to review the quality of the calibration. The flag is triggered by image saturation or undersaturation, length of time between the image and the shutter image, noise evaluation of the shutter image, and yaw angle of ODY spacecraft. DCS Decorrelation Stretch Image - These four panel images include three DCS images and a surface temperature image. The DCS images are generated by stretching correlated radiances of the following band combinations: band 8, 7, 5 (left DCS panel); bands 9, 6, 4 (middle DCS panel); and bands 6, 4, 2 (right DCS panel). See THEMIS geometry.pdf for more information. Description Description of the image given by the mission planner. When selecting by description, all text entered into the field will be directly compared with available descriptions. Duration The length of time (in seconds) requried to collect all frames of all bands in the downlinked image; typical values range from 0.5 to 450. Dust Opacity Average derived dust opacity (9µm) for a warm, daytime IR image; typical values range from 0.05 to 0.25. EDR Experiment Data Record - This file contains the raw THEMIS science data at the full resolution returned from the spacecraft, time ordered, with duplicates and transmission errors removed. This file is a PDS SPECTRAL_QUBE object with an attached PDS label. See THEMIS sdpsis.pdf for more information. Emission Angle Measured from the center of the image, this is the angle between THEMIS and a "normal" drawn perpendicular to the planet's surface. In most cases, THEMIS is looking "straight down", thus, the emission angle is close to 0°. False Color Generates a false color image from three bands of a multi-band VIS image. By default, bands 3,2,1 are represented in red, green, and blue; however, any three band combination can be generated by editing the "band=321" phrase in the url. GEO Geometrically Registered Record - This file contains the geometric projection of the RDR standard data product; the data is stored as a multispectral ISIS CUBE file and associated with a PDS-style, detached label. Note that additional manipulation of the source data may invalidate the calibrated radiance values. See THEMIS geometry.pdf for more information. Geometry Source Description of the geometry kernels used by the ISIS software when generating geometric information for this image. Valid values: "Not available", "Predicted", "Reconstructed", "Nadir Pointing Assumed". Image ID A unique identifier for each image commanded; follows the pattern Xoooooiii, where X is the image type (I, R, S, or V) ooooo is the zero padded, 5 digit orbit number iii is the zero padded, 3 digit image number Image Rating Subjective assessment of image quality ranging from unusable to good; assesment includes consideration of exposure, missing lines, instrument noise, and atmospheric features. Image Size The size in pixels of the image qube along each axis (sample, line, band). Incidence Angle Derived for the center of the image, this is the angle between the Sun and a "normal" drawn perpendicular to the surface of the planet at the time the image was acquired. An angle of 0 degrees means the Sun is directly overhead and an angle of 90 degrees means the Sun is on the horizon. "DAY" images have an incidence angle of 0-90 degrees "NIGHT" images have an incidence angle of 90-180 degrees Latitude This is the approximate latitude on the planet Mars of the image center. All values are based on the IAU 2000 aerocentric model of Mars with east positive longitude. Line Resolution The vertical size of a pixel at the center of the image as projected onto the surface of the target; units are given with the value. Local Time This is the local time on Mars at the center of the image relative to a division of the martian day into 24 equal parts. A martian day is slightly longer than 24 hours and 37 minutes long. "DAY" images are those with a local time of 08:00-20:00 (8am-8pm) "NIGHT" images are those with a local time of 00:00-07:59 or 20:01-24:59 (0:00-7:59am or 8:01-11:59pm) Longitude This is the approximate longitude on the planet Mars of the image center. All values are based on the IAU 2000 aerocentric model of Mars with east positive longitude. Mars Year The Mars year during which this image was collected. Following the convention established in Clancy [JGR April 2000, 1999JE001089], the first Themis mapping images were collected during Mars year 25. Modification Date Time of creation of this QUBE on the ground (in UTC). MOLA Elevation The average elevation value at the center of the image; values are derived from a 2 pixel per degree MOLA elevation map. North Azimuth The clockwise angle from an imaginary three o'clock axis with the origin at the center of a pixel at the center of the image. Percent Missing Percent of total lines missing from this image; valid values range from 0 to 100, where 100 indicates complete data loss. Pixel Aspect Ratio The ratio of the height (Line Resolution) to the width (Sample Resolution) of the projection of the pixel onto the surface of the target. Orbit Spacecraft orbit during which this image was observed. Phase Angle This is the angle between the sun, the surface, and THEMIS at the time the picture was obtained. Record Number Records are numbered per each unique search defined, with the total number of records shown at the top of the Results table. Within each set, records are ordered by data collection time. Release Id Four digit, zero padded identification number of the original public release of this image; see THEMIS release.html for more information. RDR Reduced Data Record - This file contains the radiometrically calibrated version of the THEMIS EDR standard data products. This file is a PDS SPECTRAL_QUBE object with an attached PDS label. See THEMIS sdpsis.pdf for more information. Sample Resolution The horizontal size of a pixel at the center of the image as projected onto the surface of the target; units are given with the value. Slant Distance This number is similar to the spacecraft altitude, but also takes into account the emission angle; if the emission angle is 0 then this number is the same as the spacecraft altitude. If the emission angle is much greater than 0, then the "slant distance" to the surface at the center of the image is also greater than the spacecraft altitude. Spatial Summing Spatial average of NxN pixels of data before downlink; summing=1 implies that no spatial averaging has been applied. VIS images have summing modes of 1, 2, and 4; IR images have summing modes of 1-320. Solar Longitude This is the position of Mars relative to the Sun measured in degrees from the vernal equinox (start of northern Spring). This number is used as a measure of martian seasons: Northern Spring/Southern Autumn start at 0° Northern Summer/Southern Winter start at 90° Northern Autumn/Southern Spring start at 180° Northern Winter/Southern Summer begin at 270° Also known as heliocentric longitude and abbreviated Ls. Stage THEMIS standard data product abbreviation: EDR, RDR, ABR, or BTR. See Glossary entries or THEMIS sdpsis.pdf for more information. Start Time The time of data acquisition of the leading edge of the detector array (filter 1); value is given in spacecraft event time (SCET) UTC format. Stretches (S1, S2, S3) - Performs a linear stretch on the image such that the variance is set to 30, 40, and 50 for S1, S2, and S3, respectively. (H1, H2, H3) - Performs a gaussian histogram stretch on the image such that sigma is set to 1.5, 2.0, and 2.5 for H1, H2, and H3, respectively. Sub-Solar Azimuth The angle in degrees relative to three o'clock positive clockwise at the center of the image to the direction of the Sun at the time the image was acquired. It tells you which direction the Sun is coming from in the image. Temperature Search is based on average surface temperature (in degrees Kelvin) derived from Band 9 in the IR image. Thermal Inertia Average thermal ineratia a each cold, nighttime IR image, derived using Keiffer's KRC thermal model. Model allows for inertia values between 20 and 2000. Thumbnail The thumbnail image represents the highest level of processing obtained by the THEMIS team for the image. For VIS images, the thumbnail is usually the geometric projection of band 3. For IR images, the thumbnail is either the DCS Image, or the BTR of band 9. For images without higher level processing, the thumbnail is based on the EDR. Water Ice Opacity Average derived water ice opacity (11µm) for a warm, daytime IR image; typical values range from 0.0 to 0.15.