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THE MARS RECONNAISSANCE ORBITER (MRO) COMPACT RECONNAISSANCE IMAGING SPECTROMETER FOR MARS (CRISM) TEAM IS DELIVERING TO THE PLANETARY DATA SYSTEM (PDS) TWO SUITES OF HIGH LEVEL DATA PRODUCTS AND VISUALIZATIONS THAT PRESENT THE SURFACE SPECTRAL INFORMATION CONTENT OF CRISM HYPERSPECTRAL TARGETED OBSERVATIONS WITH SYSTEMATIC CORRECTIONS FOR ATMOSPHERIC GAS ABSORPTIONS AEROSOL SCATTERING PHOTOMETRIC EFFECTS AND INSTRUMENT ARTIFACTS. THE CORRECTION OF THESE EFFECTS MAKES THE DATA MUCH MORE ACCESSIBLE TO THE MARS SCIENCE COMMUNITY AS COMPARED TO THE CRISM PDS STANDARD PRODUCT TARGETED REDUCED DATA RECORDS (TRDRS - CALIBRATED SPECTRAL RADIANCE AND REFLECTANCE). TARGETED EMPIRICAL RECORDS (TERS) CONTAIN THE FULLY CORRECTED FULL SPECTRAL RANGE DATA IN SENSOR SPACE AND THE MAP-PROJECTED TARGETED REDUCED DATA RECORDS (MTRDRS) ARE MAP PROJECTED TERS WITH BAD BANDS AND SPATIALLY DISCONNECTED FRAMES REMOVED. EACH PRODUCT SUITE INCLUDES CORRECTED I/F DATA SPECTRAL PARAMETER MAPS AND EASILY VIEWED BROWSE VERSIONS OF THE DATA. THE MTRDRS ARE PROJECTED USING MRO STANDARDS AND ARE GIS-READY WITH AN ESRI COORDINATE SYSTEM STRING IN EACH PRODUCT HEADER. CRISM TARGETED OBSERVATIONS USE IMAGE MOTION COMPENSATION TO ENHANCE SNR. THE REQUISITE GIMBAL MOTION INTRODUCES CONTINUOUS VARIATIONS IN THE EMISSION AND PHASE ANGLE GEOMETRY WITH ATTENDANT VARIATIONS IN ATMOSPHERIC PATH LENGTH AND AEROSOL SCATTERING ACROSS THE SCENE. FOR THE FIRST SIX YEARS OF ORBITAL OPERATIONS CRISM TARGETED OBSERVATIONS CONSISTED OF A HIGH SPATIAL RESOLUTION CENTRAL SCAN AND AN ACCOMPANYING SET OF EMISSION PHASE FUNCTION (EPF) SCANS - SPATIALLY OVERLAPPING REDUCED SPATIAL RESOLUTION IMAGES ACQUIRED BEFORE AND/OR AFTER THE CENTRAL SCAN USING THE FULL ANGULAR RANGE OF THE GIMBAL. THE EXTENDED ANGULAR SAMPLING PROVIDES THE BASIS FOR A KEY COMPONENT OF THE TER/MTRDR DATA PROCESSING - THE EMPIRICAL GEOMETRIC NORMALIZATION (EGN) PROCEDURE - WHICH MAKES USE OF THE EPFS TO CHARACTERIZE AND CORRECT STRUCTURE IN THE CENTRAL SCAN TRACEABLE TO THE CONTINUOUSLY VARYING GEOMETRY. BEGINNING 10/01/2012 THE CRISM GIMBAL RANGE HAS BEEN RESTRICTED TO AN ASYMMETRIC PORTION OF THE CENTRAL SCAN DUE TO A HARDWARE MALFUNCTION. TARGETED OBSERVATIONS ACQUIRED SINCE DO NOT HAVE ACCOMPANYING EPFS AND DO NOT MEET THE PREREQUISITES OF THE EGN PROCEDURE. THE REDUCED GIMBAL RANGE OBSERVATIONS RELEASED TO THE PDS (ACQUIRED THROUGH 11/08/2017) NOW COMPOSE ~24.3% OF THE CRISM TARGETED OBSERVATION ARCHIVE. THE PROPOSED ACTIVITY ENTAILS: (1) THE DEVELOPMENT TESTING AND IMPLEMENTATION OF A BOOTSTRAP APPROACH TO AN EGN-LIKE CORRECTION FOR TARGETED OBSERVATIONS THAT DO NOT HAVE ACCOMPANYING EPFS. THE DEVELOPMENT CONCEPT IS TO ESTABLISH A LOOK-UP TABLE OF CORRECTION FORMS FROM THE ARCHIVE OF TER/MTRDR-PROCESSED OBSERVATIONS. THE MOST APPROPRIATE CORRECTION FORM FOR A GIVEN EPF-LESS OBSERVATION WILL BE IDENTIFIED ACCORDING TO DISCRIMINATING CHARACTERISTICS SUCH AS ATMOSPHERIC STATE PHASE ANGLE RANGE SEASON SOLAR AZIMUTH ANGLE AND GEOGRAPHIC LOCATION. (2) THE GENERATION OF THE TER/MTRDR DATA PRODUCT SUITE FOR EACH EPF-LESS OBSERVATION FOR WHICH AN APPROPRIATE CORRECTION FORM CAN BE ESTABLISHED. (3) THE VALIDATION OF EACH RESULTANT PRODUCT SET USING THE EXISTING CRISM PDS SPECIAL PRODUCT RELEASE REVIEW SYSTEM. THIS REVIEW AND COMMENTING SYSTEM ALLOWS INADEQUATELY CORRECTED PRODUCTS TO BE INTERCEPTED AND QUALITY FLAGS AND COMMENTS TO BE RECORDED FOR EACH PRODUCT. (4) THE PDS DELIVERY OF THE VALIDATED PRODUCT SET AS AN AUGMENTATION OF THE EXISTING CRISM TER/MTRDR ARCHIVE CURATED AT THE PDS GEOSCIENCES NODE. THE PROPOSED CRISM DATA PROCESSING DEVELOPMENT EFFORT AND DATA PRODUCT GENERATION VALIDATION AND PDS DELIVERY ARE RELEVANT TO THE PDART PROGRAM AS THE PRODUCTS INCORPORATE HIGHER ORDER SPATIAL AND SPECTRAL CORRECTIONS AND INFORMATION CONTENT VISUALIZATIONS THAT WILL IMPROVE THE ACCESSIBILITY AND SCIENTIFIC UTILITY OF THE CRISM HYPERSPECTRAL TARGETED OBSERVATION DATA SET.

$338,422FY2020National Aeronautics and Space AdministrationNASA

The Johns Hopkins University

Investigators

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