CCSD3ZF0000100000001NJPL3IF0PDS200000001 = SFDU_LABEL RECORD_TYPE = STREAM SPACECRAFT_NAME = GALILEO_ORBITER INSTRUMENT_NAME = "NEAR_INFRARED_MAPPING_SPECTROMETER" INSTRUMENT_ID = NIMS OBJECT = TEXT NOTE = "Introduction to the Galileo Near-Infrared Mapping Spectrometer (NIMS) Experiment Data Records (EDRs) CD-ROM." PUBLICATION_DATE = 1993-12-15 END_OBJECT = TEXT END Contributions by: Bob Mehlman , Frank Leader Institute of Geophysics and Planetary Physics University of California Los Angeles, California Chris Isbell , Eric Eliason United States Geological Survey Branch of Astrogeology 2255 North Gemini Drive Flagstaff, Arizona 86001 Sue Hess , Bill Smythe Jet Propulsion Laboratory 4800 Oak Grove Drive Oak Grove Drive Pasadena, CA 91109 December 1, 1993 Version 1.0 CONTENTS 1 - INTRODUCTION 2 - GALILEO MISSION 3 - NIMS INSTRUMENT 4 - NIMS EDR FILE 5 - DISK DIRECTORY STRUCTURE 6 - INDEX FILES 7 - CALIBRATION FILES 8 - SOFTWARE 9 - KEYWORD DESCRIPTIONS 10 - DATA PROCESSING CONSIDERATIONS 11 - WHOM TO CONTACT FOR INFORMATION 12 - ACKNOWLEDGEMENTS 13 - REFERENCES 1 - INTRODUCTION This CDROM contains the raw data for the Galileo-NIMS experiment from launch (Oct 18, 1989) through the Earth 1 encounter (December 8, 1990). It has, in addition, software for elementary display of the data. This document and the AAREADME.TXT file in the top level directory of this disk provide relevant information pertaining to this CD-ROM. 2 - GALILEO MISSION Galileo is a mission to Jupiter to perform long-term studies of the Jovian atmosphere and detailed studies of the Galilean satellites. The mission is divided into a launch/cruise phase and an orbital phase. The spacecraft trajectory required a deltaV Venus-Earth-Earth gravity assist (VEEGA). The cruise is divided into Earth-Venus (EV), Venus-Earth (VE), Earth-Earth (EE) and Earth-Jupiter segments -- with the initials used to associate observations with time. These cruise segments are further divided by spacecraft command loads, which are numbered, but not completely contiguously since some planned loads were later combined or eliminated. Important segments include VE6 (Venus encounter), EV9 and 11 (Earth 1 encounter), EE3 (Gaspra encounter) and EE9 and 11 (Earth 2 encounter). The spacecraft is a dual-spinner, with the fundamental coordinate system in EME-1950 (Right Ascension, Declination, and Twist) and a hardware coordinate system in cone and clock. The associated spacecraft geometry is available as SPICE kernels generated by the NAIF group at JPL. The fundamental unit of the spacecraft clock is the RIM ((Realtime Imaging count, 60 2/3 seconds). This is subdivided into 91 minor frames (2/3 seconds each) numbered from 0 to 90. Each minor frame is in turn subdivided into 10 RTIs (RealTime Interrupts), numbered 0 to 9. The spacecraft clock time is usually represented in the notation RIM:MF:RTI, where MF denotes the minor frame. Planned spacecraft events are described in the SSDF (Standard Sequence Data File). It is the source of several other files, including the ORPLN (ORbit PLaNning) file, the SEF (Spacecraft Event File) and the ISOE (Integrated Sequence Of Events) file. These are available through the Galileo Science Catalog. 3 - NIMS INSTRUMENT The Near-Infrared Mapping Spectrometer (NIMS) instrument is an imaging spectrometer covering the wavelength region 0.7 to 5.2 micrometers -- a region not studied by the Pioneer and Voyager spacecraft. Its spectral resolution is 0.025 micron beyond 1 micron, and 0.0125 microns below 1 micron, yielding 204 spectral elements in nominal mode. The nominal pixel size is a square 0.5 x 0.5 milliradians. The instrument acquires data in the order: (1) sampling of 17 detectors, (2) stepping of the scan mirror (20 elements in cross-cone), (3) stepping of the grating (nominally 12 steps per cycle). The nominal 204 wavelength cycle requires 4 1/3 seconds. The detectors (2 silicon, 15 Indium Antinomide) sample approximately uniformly across the spectrum. A detailed description of the instrument may be found in [1]. Earlier descriptions may be found in references [2,3]. An electronic version of a preprint of [1] is available in the [DOCUMENT.NIMSINST] directory of this CD-ROM. The raw instrument data is organized by spacecraft clock. With a knowledge of the start and stop time of a given observation, the data can be organized into a viewable object, normally known as a qube, stacked images with spatial coordinates on the front and spectral coordinates along the "back" axis. The timing of the instrument data acquisition, with 17 detectors at a grating position sampled at (nearly) the same time, results in slightly offset geometry for each grating step. This is normally adjusted by resampling the data. First results of NIMS observations during the Galileo Venus encounter may be found in [4]. 4 - NIMS EDR FILE NIMS Experiment Data Record (EDR) files are generated by the Multimission Image Processing System (MIPS) at the Jet Propulsion Laboratory (JPL). They are divided into files containing up to 100 RIMs of data. Each file contains the best data available from the several ground stations receiving Galileo telemetry. The files consist principally of 10-bit NIMS sensor values from the 17 detectors, but they also contain NIMS background and housekeeping values, instrument temperatures and other engineering measurements. The data are organized into 1024-byte records, one for each minor frame (2/3 second) of spacecraft clock time. In that time, the NIMS instrument has collected sensor values for all 17 detectors over two scans (20 positions down and 20 positions up) of the secondary mirror. A detailed description of the structure of the EDR may be found in the Galileo Software Interface Specification (SIS, [5]). The same information is available in both human and machine-readable form in the Planetary Data System (PDS) structure files EDRHDR.FMT and EDRDATA.FMT in the LABEL directory of this CD. For information on PDS standards see references [6,7,8,9]. NIMS EDR data require considerable processing before they are readily amenable to science analysis. Normally, the EDRs are processed into spectral image cubes by one of several sets of software. (See section 10 of this document for further information.) As received from MIPS, each file has a Vicar label preceding a PDS/ISIS label. The Vicar label has been removed from the EDRs on this CD-ROM, but it has been saved in a separate directory and software has been provided to re-attach it. The PDS/ISIS-labelled EDRs themselves are readily processable by software in the ISIS system, and by PDS utilities. For additional information on ISIS and Vicar system availability and related technical support, see "Whom to Contact for Information", section 11 of this document. 5 - DISK DIRECTORY STRUCTURE The files on this CD-ROM are organized by several top-level directories with subdirectories where appropriate. The following table shows the structure and content of these directories. In the table, directory names are followed by a designation, upper-case letters indicate an actual directory or file name, and lower-case letters indicate the general form of directory names or file names. In the case of the [SOFTWARE.SUN] directory, lower case file names are used as they appear on a SUN/UNIX system. DIRECTORY or FILENAME CONTENTS Top-level or root directory |- AAREADME.TXT Introduction to the NIMS EDR CD-ROM. | |- AAREADME.VMS Basic introduction for VMS systems. | |- VOLDESC.SFD A description of the contents of this CD-ROM volume in a format readable by both humans and computers. DOCUMENT This directory contains document files | (extension name "TXT") describing products, | missions, organization, etc.. | |- VOLINFO.TXT Contains detailed information about the | contents of this CD-ROM volume. | |- NIMSINST.TXT A breif description, with references, of the | Near Infrared Mapping Spectrometer (NIMS) | instrument. Each EDR has a label pointer to | this file. | |- NIMSGD This directory contains the NIMS Guide to the | | Venus and Earth 1 encounters. | | | |- GDINFO.TXT Documentation describing the contents of the | | NIMSGD directory. | | | |- NIMSGD.LBL PDS label describing the NIMS Guide formats | | | |- NIMSGDn.ASC Ascii versions of portions of the NIMS Guide. | | (Chapters n=1,3,4,5, and n=A for Appendix A) | | | | (PostScript Versions of the NIMS Guide) | |- NIMSGDTP.PS Title Page | | | |- NIMSGDTC.PS Table of Contents | | | |- NIMSGD1.PS Chapter 1 (Revised introduction) | | | |- NIMSGD2.PS Chapter 2: Cruise overview | | | |- NIMSGD3A.PS Chapter 3: EV6 (NIMS Venus observations) | | | |- NIMSGD3B.PS Chapter 3: EV6 (Ride-along Venus observations) | | | |- NIMSGD4.PS Chapter 4: VE9 (Pre-encounter calibration observations) | | | |- NIMSGD5.PS Chapter 5: VE11 (Earth/Moon observations) | | | |- NIMSGD5S.PS Chapter 5: VE11 spreadsheet | | | |- NIMSGDA.PS Appendix A: Original introduction | |- NIMSINST This directory contains a preprint of the NIMS | instrument paper. | |- INSTINFO.TXT Documentation describing the contents of the | NIMSINST directory. | |- INSTPUB.ASC ASCII version of the Text and Tables from the | Instrument paper. | |- INSTFGnn.PS PostScript files for Figures, nn = 01-14, from | the Instrument paper. | |- INSTPUB.LBL PDS label describing ASCII and PostScript files | mentioned above. INDEX This directory contains various index table | and index label files. | |- INDXINFO.TXT Documentation describing the contents of the | INDEX directory. | |- BOOMCAT.TAB Boom Map index table. | |- BOOMCAT.LBL PDS label describing BOOMCAT.TAB content. | |- DRKCAT.TAB Dark current calibration index table. | |- DRKCAT.LBL PDS label describing DRKCAT.TAB content. | |- EDRCAT.TAB EDR information index table. | |- EDRCAT.LBL PDS label describing EDRCAT.TAB content. | |- OBSCAT.TAB Observation characteristics index table. | |- OBSCAT.LBL PDS label describing OBSCAT.TAB content. | |- RIMCAT.LBL RIM count reference index table. | |- RIMCAT.LBL PDS label describing RIMCAT.TAB content. CALIB This directory contains NIMS calibration | files. | |- CALINFO.TXT Documentation describing the CALIB directory. | |- EnGgMmVv.DRK Dark current calibration files. | |- EnGgMmVv.LBL PDS label describing the dark current file. | |- EnGgMmVv.ASC Dark current calibration files. | |- BOOMVnnn.NIM Boom Obscuration map. LABEL This directory contains detached label files | showing the format for the EDR header and data | areas of the NIMS EDR files. | |- LABINFO.TXT Documentation describing the content of the | LABEL directory. | |- EDRHDR.FMT PDS label describing EDR header area. | |- EDRDATA.FMT PDS label describing EDR Data area. SOFTWARE The subdirectories below this directory contain | source code for software used to access and | manipulate files on this CD. | |- SUN This directory contains software to be used | | on a SUN system. | | | |- softinfo.txt Documentation describing the content of the | | SUN directory. | | | |- edrchk.for Fortran program to display EDR header | |- edrchk.out information and validity statistics. | | (source and executable) | | | |- addlab.c C program which attaches VICAR label to EDR | |- addlab.out file. (source and executable) | | | |- build.com Script file used to compile and link all | | SUN programs | | | |- csubs.c All C subroutines used by SUN software. | | | |- fsubs.for All Fortran subroutines used by SUN software. | | | |- edrdat.inc Fortran 'include' files used by SUN software. | |- edrdrec.inc | |- edrhdr.inc | |- edrhrec.inc | |- wrkdat.inc | |- VAXVMS This directory contains software to be used | on a VAX-VMS system. | |- SOFTINFO.TXT Documentation describing the content of the | VAXVMS directory. | |- EDRCHK.FOR Display EDR header information and validity |- EDRCHK.EXE statistics. (source and executable) | |- EDRDMP.FOR Fortran program used to perform EDR data |- EDRDMP.EXE dumps. (source and executable) | |- ADDLAB.C C program which attaches VICAR label to EDR |- ADDLAB.EXE file. (source and executable) | |- BUILD.COM Command file used to compile and link all | VAX-VMS programs | |- CSUBS.C All C subroutines used by VAX-VMS software. | |- FSUBS.FOR All Fortran subroutines used by VAX-VMS | software. | |- EDRDAT.INC Fortran 'include' files used by VAX-VMS |- EDRHDR.INC software. |- WRKDAT.INC | |- CDCOPY.COM Command file used to copy data files from the CD. (see SOFTINFO.TXT for information) GEOMETRY This directory contains NIMS geometry files. | |- GEOMINFO.TXT Documentation describing GEOMETRY directory | |- NIMSVnn.IK Instrument kernel geometry files. (2 files) | |- NIMSV02.LBL PDS label describing NIMSV02.IK file. SPIKE Top-Level Spike directory. | |- SPIKINFO.TXT Documentation describing the SPIKE directory. | |- Cpxxxxx This directory contains NIMS Spike files. | (Empty for this Volume) | |- Spxxxxxx.xxu EDR Top-Level EDR directory. | |- Cpxxxxx This directory consists of files which contain | the NIMS EDR header and data areas of the | original NIMS EDR files. | |- Epxxxxxx.xxu NIMS EDR files with PDS label. VIC Top-Level VICAR directory. | |- Cpxxxxx This directory consists of files which contain | the detached NIMS EDR VICAR label. | |- Vpxxxxxx.xxu NIMS EDR detached VICAR label. 6 - INDEX FILES Index files are located in the INDEX directory of this disk and have file names ending with the characters ".TAB". An index file is a 'table' arranged by rows (records) and columns (fields) and provides important information about the NIMS data. Some index files are formatted to allow automatic data entry programs to access the data for entry into an existing data base system. In these tables, non-numeric fields are enclosed by double-quote characters, all fields are delimited by commas, and the last two bytes in each record are carriage-control and line-feed characters. Other table files are designed for access by ISIS cube generation software, and lack the quotes, separators and terminators. Both kinds have accompanying PDS label files whose file names end with ".LBL". Each .LBL file is a PDS Object Description Language (ODL) description of the contents of the corresponding .TAB file. ODL documentation is available within the reference 6 document. The following are index files found in the INDEX directory on this CD. Index Description ---------- ----------------------------------------------------- BOOMCAT.TAB Points to appropriate boom file for given time period DRKCAT.TAB Points to appropriate dark file for given time period RIMCAT.TAB Provides status information about each RIM count (60 2/3 seconds) of each observation OBSCAT.TAB Provides time range and status information about each observation EDRCAT.TAB Provides selected information about each EDR file. (A CALCAT.TAB table, summarizing NIMS calibration files, will be added in later CDs when the calibration files themselves are included.) The following tables (Table 1 through Table 5) provide a detailed description of the contents of each of the index files. This includes the starting and ending byte positions of each field in the index. These byte positions specify the actual fields and do not include the double-quote marks and commas that may separate the fields. Table 1 - BOOMCAT.TAB -------------------------------------- Byte Positions Description ---------------------------------------------------------------------- 2 - 9 NATIVE_START_TIME_RIM : The spacecraft start clock count that indicates the starting period when the Boom Obscuration file is to be used. 16 - 23 NATIVE_STOP_TIME_RIM : The spacecraft stop clock count that indicates the ending period when the Boom Obscuration file is to be used. 30 - 36 BOOM_VOLUME_ID : The CD_ROM volume containing the Boom Obscuration files referenced in the table. BOOM_VOLUME_ID = "GO_1001" for all files on this CD-ROM. 40 - 59 BOOM_FILE_NAME : The name of the boom obscuration file to use for a NIMS data set for the indicated time periods (start and stop native time). BOOM_FILE_NAME = "[CALIB]BOOMV001.NIM" for all files on this CD-ROM. Table 2 - DRKCAT.TAB -------------------------------------- Byte Positions Description ---------------------------------------------------------------------- 2 - 9 NATIVE_START_TIME : The spacecraft clock count that indicates the beginning of the period of applicability of the file. 16 - 23 NATIVE_STOP_TIME : The spacecraft clock count that indicates the end of the period of applicability of the file. 30 - 30 GAIN_MODE_ID : The gain state of the NIMS instrument. There are 4 NIMS gain states, designated by numerals 1 to 4. Separate dark current files may exist for each combination of gain state and instrument mode. 34 - 34 INSTRUMENT_MODE_ID : The mode of the NIMS instrument when the dark values were collected. 38 - 44 DARK_CURRENT_VOLUME_ID : The CD_ROM volume containing the dark current files referenced in the table. 48 - 67 DARK_CURRENT_FILE_NAME : The file name of the dark current file to use for a NIMS data set for the indicated time periods (start and stop native time) and gain state. Table 3 - RIMCAT.TAB -------------------------------------- 1 - 8 NATIVE_TIME_RIM : Spacecraft clock Realtime IMage count. 10 - 26 TIME : Universal Time corresponding to the beginning of the spacecraft clock RIM in ISO format. 28 - 29 INSTRUMENT_MODE_NUMBER : A number (0-15) which identifies the NIMS instrument mode during the RIM: 0 Safe (fixed spectrometer) 1 Full map 2 Full spectrometer 3 Long map 4 Long spectrometer 5 Short map 6 Short spectrometer 7 Fixed map 8 Bandedge map 9 Bandedge spectrometer 10 Stop and slide map 11 Stop and slide spectrometer 12-15 Special sequences (programmable modes) 31 - 32 GAIN_MODE_NUMBER : A number which identifies the gain state (1-4) of the NIMS instrument during the RIM. These states vary roughly from low gain (1) to high gain (4) and apply to the non-thermal detectors (1-14) only. 34 - 35 CHOPPER_MODE_NUMBER : A number which identifies the chopper mode of the NIMS instrument during the RIM: 1 Reference mode 2 63-hertz mode 3 Free-run 4 Off 37 - 38 GRATING_OFFSET : The physical offset (0-7) of the NIMS grating during the RIM. It defines the physical grating position of logical grating position 0. 39 - 74 The contents of the two Parameter Tables (PTABs) in the NIMS instrument. The PTABs control the operation of the instrument. Six items have been extracted from each 4-byte parameter table. 39 - 56 PTAB A 39 - 41 MODE_REPEAT_COUNT : The mode repeat count is the number of times the grating cycle defined in the PTAB is to be repeated before control is transferred to the other PTAB. It is the first byte of the PTAB. 44 MIRROR_OPERATION_FLAG : The mirror operation flag, if set, indicates that the NIMS secondary mirror is operating, i.e. the instrument is in a MAP mode. If the flag is not set, the mirror remains in position 9 (of 0-19), i.e. the instrument is in a SPECTROMETER mode. The flag is the first bit of the second byte of the PTAB. 47 AUTOBIAS_FLAG : The autobias flag, if set, means that thermal channel autobias is off. This is intended for use only when the NIMS instrument is at room temperature. The flag is normally NOT set, implying that the thermal detectors (15-17) have different gains in each half of the DN range. This flag is the second bit of the second byte of the PTAB. 49 - 50 START_GRATING_POSITION : The start grating position is the first logical position of the grating when the PTAB assumes control of the instrument. It is in the 6 least significant bits of the second byte of of the PTAB. 52 - 53 GRATING_POSITION_INCREMENT : The grating position increment controls the step size between grating positions. It is the third byte of the PTAB. 55 - 56 GRATING_POSITIONS : The number of grating positions (separated by the grating position increment) in one repetition of the operation defined in the PTAB, except for fixed map and safe modes, in which it governs only the motions of the secondary mirror. It is the fourth byte of the PTAB. 57 - 74 PTAB B (see PTAB A above for description and relative location of fields) 77 - 77 ELECTRONICS_CALIBRATION_FLAG : An electronic calibration of the NIMS instrument will occur during the RIM if the flag is set. 80 - 80 OPTICAL_CALIBRATION_FLAG : An optical calibration of the NIMS instrument will occur during the RIM if the flag is set. 83 - 83 NEW_COMMAND_FLAG : If the flag is set, a new command was received by the instrument. 85 - 96 OAPEL_ID : The Orbital Activity Profile ELement ID identifies the planned observation to which the RIM belongs. It is popularly known as the OAPEL name. 98 - 98 SEGMENT_ID : The segment ID identifies a part of an observation which has been separated for processing convenience. (Parts of observations in different instrument modes are usually processed separately.) Ordered segments within an observation are usually represented by alphabetic characters in order, beginning with 'A'. 100 - 107 PRIMARY_TARGET_NAME : The primary target of the observation to which the RIM belongs. Besides the various planets and satellites, this may be SKY, STAR (for boresight calibration), DARK (for dark calibrations) or CAL (for optical and radiometric calibrations). Table 4 - OBSCAT.TAB -------------------------------------- 1 - 12 OAPEL_ID : The Orbital Activity Profile ELement ID identifies a single planned observation. It is popularly known as the OAPEL name. 14 - 14 SEGMENT_ID : The segment ID identifies a part of an observation which has been separated for processing convenience. (Parts of observations in different instrument modes are usually processed separately.) Ordered segments within an observation are usually represented by alphabetic characters in order, beginning with 'A'. 16 - 19 PROFILE_ACTIVITY_ID : The profile activity ID identifies the type of scan platform activity of the observation segment. Only the first 4 characters of each identifier are used in the table: ALSPINSP All Spin Scan Platform Control CMDRS Instrument Command (Remote Sensing) CSMOS Continuous Slew Mosaic INITRS Instrument Initialization (Remote Sensing) PCINIT Photocalibration Initialization PCREST Photocalibration Restore (termination) RADHTR NIMS Radiometric Heater Control SCIREC Science Record SCITLM Science Telemetry SMOS Start/Stop Slew Mosaic TARGET Target (Scan Platform Positioning) SSI Solid State Imaging (SSI) Command UTIL Utility, such as instrument checkout 21 - 31 NATIVE_START_TIME : The spacecraft clock count that indicates the beginning of the observation segment. 33 - 43 NATIVE_STOP_TIME : The spacecraft clock count that indicates the end of the observation segment. 45 - 46 INSTRUMENT_MODE_NUMBER : A number (0-15) which identifies the NIMS instrument mode during the observation segment: 0 Safe (fixed spectrometer) 1 Full map 2 Full spectrometer 3 Long map 4 Long spectrometer 5 Short map 6 Short spectrometer 7 Fixed map 8 Bandedge map 9 Bandedge spectrometer 10 Stop and slide map 11 Stop and slide spectrometer 12-15 Special sequences (programmable) 49 - 49 GAIN_MODE_NUMBER : A number which identifies the gain state (1-4) of the NIMS instrument during the observation segment. These states vary roughly from low gain (1) to high gain (4) and apply to the non-thermal detectors (1-14) only. 52 - 52 CHOPPER_MODE_NUMBER : A number which identifies the chopper mode of the NIMS instrument during the observation segment: 1 Reference mode 2 63-hertz mode 3 Free-run 4 Off 55 - 55 GRATING_OFFSET : The physical offset (0-7) of the NIMS grating during the observation segment. It defines the physical grating position of logical grating position 0. 56 - 91 The contents of the two Parameter Tables (PTABs) in the NIMS instrument. The PTABs control the operation of the instrument. Six items have been extracted from each 4-byte parameter table. 56 - 73 PTAB A 56 - 58 MODE_REPEAT_COUNT : The mode repeat count is the number of times the grating cycle defined in the PTAB is to be repeated before control is transferred to the other PTAB. It is the first byte of the PTAB. 61 MIRROR_OPERATION_FLAG : The mirror operation flag, if set, indicates that the NIMS secondary mirror is operating, i.e. the instrument is in a MAP mode. If the flag is not set, the mirror remains in position 9 (of 0-19), i.e. the instrument is in a SPECTROMETER mode. The flag is the first bit of the second byte of the PTAB. 64 AUTOBIAS_FLAG : The autobias flag, if set, means that thermal channel autobias is off. This is intended for use only when the NIMS instrument is at room temperature. The flag is normally NOT set, implying that the thermal detectors (15-17) have different gains in each half of the DN range. This flag is the second bit of the second byte of the PTAB. 66 - 67 START_GRATING_POSITION : The start grating position is the first logical position of the grating when the PTAB assumes control of the instrument. It is in the 6 least significant bits of the second byte of of the PTAB. 69 - 70 GRATING_POSITION_INCREMENT : The grating position increment controls the step size between grating positions. It is the third byte of the PTAB. 72 - 73 GRATING_POSITIONS : The number of grating positions (separated by the grating position increment) in one repetition of the operation defined in the PTAB, except for fixed map and safe modes, in which it governs only the motions of the secondary mirror. It is the fourth byte of the PTAB. 74 - 91 PTAB B (see PTAB A above for description and relative location of fields) 94 - 94 ELECTRONICS_CALIBRATION_FLAG : An electronic calibration of the NIMS instrument will occur in the first RIM of the observation if the flag is set. 96 - 96 OPTICAL_CALIBRATION_FLAG : An optical calibration of the NIMS instrument will occur in the first RIM of the observation if the flag is set. 98 - 114 START_TIME : The start time of the observation as a Universal Time in ISO format, corresponding to NATIVE_START_TIME. 117 - 117 REALTIME_FLAG : If the flag is set, the observation was transmitted in the realtime data stream. 119 - 119 RECORD_FLAG : If the flag is set, the observation was recorded on the Galileo tape recorder and transmitted later. 121 - 128 PRIMARY_TARGET_NAME : The primary target of the observation. Besides the various planets and satellites, this may be SKY, STAR (for boresight calibration), DARK (for dark calibrations) or CAL (for optical and radiometric calibrations). Table 5 - EDRCAT.TAB -------------------------------------- Byte Positions Description ---------------------------------------------------------------------- 2 - 8 CD_VOLUME_ID : The CD_ROM volume containing the EDR and VICAR files referenced in the table. 12 - 36 VICAR_FILENAME : The CD_ROM directory and file name for the VICAR label. The naming convention for the VICAR directory name and filename is as follows : Directory name : VIC.Cpxxxxx File name : Vpxxxxxx.xxu where : p = Spacecraft clock partition code. ( 1 or 2 ) xxxxx = first five digits of the spacecraft clock count. xxxxxx.xx = Eight digit RIM count(spacecraft clock count). u = Uniqueness code (A or B , B is used when two EDRs have the same starting RIM count). 40 - 64 EDR_FILENAME : The CD_ROM directory and file name for the EDR data file. The naming convention for the VICAR directory name and filename is as follows : Directory name : EDR.Cpxxxxx File name : Epxxxxxx.xxu (See VIC_FILENAME description for filename interpretation) 68 - 94 SPIKE_FILENAME : The CD_ROM directory and file name for the Spike file(N/A for this volume). For future volumes the naming convention for the SPIKE directory name and filename is as follows : Directory name : SPIKE.Cpxxxxx File name : Spxxxxxx.xxu (See VIC_FILENAME description for filename interpretation) 98 - 104 SPIKE_CD_VOLUME_ID : The CD_ROM volume which contains the most up to date spike information for the current record(N/A for this volume). 108 - 142 MISSION_PHASE_NAME : Defines the mission phase during native data acquisition. 146 - 165 TARGET_NAME_1 : The first target within frame count range. 169 - 188 TARGET_NAME_2 : The second target within frame count range. 192 - 211 TARGET_NAME_3 : The third target within frame count range. 215 - 234 TARGET_NAME_4 : The fourth target within frame count range. 238 - 257 TARGET_NAME_5 : The fifth target within frame count range. 261 - 285 DATA_SET_ID : The data_set_identification element is the unique alphanumeric identifier for this data set or a data product. The data_set_identification value for a given data set or product is constructed according to PDS naming conventions. 289 - 313 SPACECRAFT_NAME : The name of the spacecraft which hosts the instrument referenced in INSTRUMENT_ID object. 317 - 341 INSTRUMENT_ID : The instrument_identification element provides an abbreviated name or acronym which identifies the instrument. 345 - 355 NATIVE_START_TIME : The spacecraft start clock count for the EDR data. (rrrrrrrr.mm) 359 - 369 NATIVE_STOP_TIME : The spacecraft stop clock count for the EDR data. (rrrrrrrr.mm) 372 - 375 MINOR_FRAME_COUNT : The number of minor frames acquired within the EDR data. 378 - 397 EARTH_RECEIVED_START_TIME : The Universal Time Coordinated(UTC) at which spacecraft telemetry acquisition starts on earth. 401 - 420 EARTH_RECEIVED_STOP_TIME : The Universal Time Coordinated(UTC) at which spacecraft telemetry acquisition stops on earth. 424 - 443 PRODUCT_CREATION_TIME : The Universal Time Coordinated(UTC) at which the NIMS EDR product is generated. 446 - 451 MEAN_FOCAL_PLANE_TEMPERATURE : The mean temperature of the focal plane during data acquisition. 453 - 458 MEAN_RADIATOR_SHIELD_TEMPERATURE : The mean temperature of the radiator shield during data acquisition. 460 - 465 MEAN_TELESCOPE_TEMPERATURE : The mean temperature of the telescope during data acquisition. 467 - 472 MEAN_GRATING_TEMPERATURE : The mean temperature of the grating during data acquisition. 474 - 479 MEAN_CHOPPER_TEMPERATURE : The mean temperature of the optical chopper during data acquisition. 481 - 486 MEAN_ELECTRONICS_TEMPERATURE : The mean temperature of the instrument electronics during data acquisition. 488 - 492 VALID_NIMS_LRS_COUNT : Total number of valid NIMS Low Rate Science (LRS) packets in the data records. 494 - 498 VALID_AACS_LRS_COUNT : Total number of valid Attitude and Articulation Control System (AACS) Low Rate Science packets in the data records. 500 - 504 GCF_ERRORS : Total number of data records in the EDR file with Ground Communications Facility (GCF) block errors. 506 - 510 NIMS_GOLAY_ERRORS : Total number of data records in the EDR file containing NIMS LRS packets with possible Golay error. 512 - 516 AACS_GOLAY_ERRORS: Total number of data records in the EDR file containing AACS LRS packets with possible Golay error. 518 - 522 TOTAL_GOLAY_ERRORS : Total number of data records in the EDR file containing Golay errors. 525 - 529 PSEUDO_NOISE_ERROR_FLAG : Pseudo-noise number contained bit errors, spacecraft clock was corrected. 533 - 537 SPACECRAFT_CLOCK_ERROR_FLAG : Spacecraft clock errors found, spacecraft clock was corrected. 7 - CALIBRATION FILES The CALIB directory contains several data files required for (non- geometric) processing of the data acquired by the NIMS instrument: BOOMV001.NIM is the map of Galileo boom obscurations (provided by Kay Edwards) as a function of scan platform cone and clock angles. It is used by the NIMSBOOMSTEN ISIS program, as well as the Vicar cube generation software. E1G1MLV1.DRK, E1G1MLV2.DRK, E1G1MLV3.DRK and E1G1MFV1.DRK are average dark current files derived from "heaven dark" observations at different times in the E1 encounter. They contain VAX floating point numbers for use by the RADGEN program in the ISIS cube generation set, and by the Vicar cube generation software. ASCII text versions are also provided (with .ASC extension). These contain not only the average dark current values, but their standard deviations, as well as a histogram of their occurrence. (The number following the G in the filename represents the gain state, and the letter following the V represents the mode: L=long, F=full. The number after the V is a version number.) Calibration files are not present in this volume of NIMS EDRs, but will be placed in this directory on later volumes. 8 - SOFTWARE 8.1 - SOFTWARE DISCLAIMER The SOFTWARE directory consists of two subdirectories. The VAXVMS and SUN subdirectories contain source code files for simple data manipulation and access functions for the NIMS Experiment Data Record (EDR) files contained on this CD-ROM. The software in each directory are specific to the operating systems implied by the directory name. The SOFTINFO.TXT files within each of the SOFTWARE subdirectory provide detailed documentation on directory content and how to make use of the provided software. Although the software contained on this CDROM has been used and tested, no warranty, expressed or implied, is made by NASA, the Jet Propulsion Laboratory (JPL), or the United States Geological Survey (USGS) as to the accuracy and functioning of the software and related materials, and no responsibility is assumed by NASA, JPL, or the USGS. 9 - KEYWORD DESCRIPTIONS Keyword Descriptions for the NIMS EDR files. -------------------------------------------- CCSD3ZF0000100000001NJPL3IF0PDS200000001 = SFDU_LABEL This keyword provides a mechanism for files on this CDROM to conform to the SFDU (Standard Formatted Data Unit) convention. The first 20 bytes identify the file as a CCSDS SFDU entity. The next 20 bytes identify the file as a registered product of the JPL SFDU control authority. The components of both SFDU labels are the control authority identifier (characters 1-4), the version identifier (character 5), the class identifier (character 6), a spare field (characters 7-8), a format identifier (characters 9-12), and a length field indicator (characters 13-20). The version identifier indicates a "Version-3" label, which allows files to be delimited by an end-of-file marker, rather than requiring a byte count to be embedded in the label. The keyword conforms to standard PDS keyword syntax and the value associated with this keyword will always be SFDU_LABEL. RECORD_TYPE = FIXED_LENGTH This keyword defines the record structure of the file. The NIMS EDR files are always fixed-length record files. This keyword always contains the value FIXED_LENGTH. RECORD_BYTES = 512 Record length in bytes for fixed length records. FILE_RECORDS = xxxx Total number of records contained in the file. LABEL_RECORDS = 6 Number of records in the label area of the image file. FILE_STATE = CLEAN Distinguishes CLEAN (good) files from DIRTY (incomplete) files. ^HEADER_TABLE = 7 The (^) character prefixing a keyword indicates that the keyword is a pointer to the starting record of a data object in the file. In this case, the keyword is the pointer to the Header Table Object. The keyword value indicates the starting record in the file for the Header Table Object. The number of records found in an object is determined by differencing the value of the pointer keyword from the value of the next pointer or to the end of the file. OBJECT = HEADER_TABLE INTERCHANGE_FORMAT = BINARY COLUMNS = UNK ROWS = 1 ROW_BYTES = 2048 ^STRUCTURE = "EDRHDR.FMT" CHECKSUM = xxxxxxxxxx END_OBJECT = HEADER_TABLE This keyword sequence describes the Header Table object. The following describes the meaning of each keyword for this sequence. INTERCHANGE_FORMAT = BINARY The interchange_format element represent the manner in which data items are stored. For the EDR files on this disk, the value is BINARY. COLUMNS = UNK The actual number of columns in a ROW is somewhat indeterminate. For this reason, the UNK value is used. The PDS and NIMS software which deals with this data ignores this element. ROWS = 1 The number of rows occupied by the HEADER_TABLE. ( Always = 1 for the EDR files on this disk. ) ROW_BYTES = 2048 The number of bytes in each ROW of this object. ( Always = 2048 for the EDR files on this disk. ) ^STRUCTURE = "EDRHDR.FMT" Filename of file describing the structure of this object. CHECKSUM = xxxxxxxxxx The sum of all the bytes within the HEADER_TABLE object. This parameter can be used to verify the reading of an EDR file. ^DATA_TABLE = 11 The (^) character prefixing a keyword indicates that the keyword is a pointer to the starting record of a data object in the file. In this case, the keyword is the pointer to the EDR Data Table Object. The keyword value indicates the starting record in the file for the Data Table Object. The remainder of the keywords apply to the DATA_TABLE object. A description follows each keyword below. OBJECT = DATA_TABLE INTERCHANGE_FORMAT = BINARY The interchange_format element represent the manner in which data items are stored. For the EDR files on this disk, the value is BINARY. COLUMNS = UNK The actual number of columns in a ROW is somewhat indeterminate. For this reason, the UNK value is used. The PDS and NIMS software which deals with this data ignores this element. ROWS = xxxx The number of rows in the EDR data portion of the file. In this case the number of minor frames of this EDR data. ROW_BYTES = 1024 The number of bytes in each ROW of this object. ( Always = 1024 for the EDR files on this disk. ) ^STRUCTURE = "EDRDATA.FMT" Filename of file describing the structure of this object. DATA_SET_ID = "GO-E/L-NIMS-2-EDR-V1.0" or = "GO-V-NIMS-2-EDR-V1.0" The PDS defined data set identifier for the NIMS EDR data. For the data on this disk, the value will be one of the ids stated above. SPACECRAFT_NAME = GALILEO_ORBITER The name of the spacecraft which acquired the NIMS EDR data. INSTRUMENT_NAME = "NEAR_INFRARED_MAPPING_SPECTROMETER" The name of the instrument which acquired the EDR data. INSTRUMENT_ID = NIMS This element provides an abbreviated name or acronym which identifies an instrument. ^INSTRUMENT_DESCRIPTION = "NIMSINST.TXT" File which contains a detailed description of the NIMS instrument. NATIVE_START_TIME = xxxxxxxxxxx NATIVE_STOP_TIME = xxxxxxxxxxx These elements provide the spacecraft start and stop clock counts for the EDR data. EARTH_RECEIVED_START_TIME = xxxxxxxxxxxxxxxxxxxx EARTH_RECEIVED_STOP_TIME = xxxxxxxxxxxxxxxxxxxx These elements provide the Universal Time Coordinated(UTC) at which spacecraft telemetry acquisition starts and stops on earth. PRODUCT_CREATION_TIME = xxxxxxxxxxxxxxxxxxxx The Universal Time Coordinated(UTC) at which the NIMS EDR product is generated. NOTE = "EDR product provided by Multimission Image Processing Laboratory of JPL, CALTECH" This note states the facility which provided the EDR data product. MEAN_FOCAL_PLANE_TEMPERATURE = xxxxx MIN_FOCAL_PLANE_TEMPERATURE = xxxxx MAX_FOCAL_PLANE_TEMPERATURE = xxxxx MEAN_RADIATOR_SHIELD_TEMP = xxxxx MIN_RADIATOR_SHIELD_TEMP = xxxxx MAX_RADIATOR_SHIELD_TEMP = xxxxx MEAN_TELESCOPE_TEMPERATURE = xxxxx MIN_TELESCOPE_TEMPERATURE = xxxxx MAX_TELESCOPE_TEMPERATURE = xxxxx MEAN_GRATING_TEMPERATURE = xxxxx MIN_GRATING_TEMPERATURE = xxxxx MAX_GRATING_TEMPERATURE = xxxxx MEAN_CHOPPER_TEMPERATURE = xxxxx MIN_CHOPPER_TEMPERATURE = xxxxx MAX_CHOPPER_TEMPERATURE = xxxxx MEAN_ELECTRONICS_TEMPERATURE = xxxxx MIN_ELECTRONICS_TEMPERATURE = xxxxx MAX_ELECTRONICS_TEMPERATURE = xxxxx These elements provide the temperatures of various components of the NIMS instrument during data acquisition. VALID_NIMS_LRS_COUNT = xxx Total number of valid NIMS Low Rate Science (LRS) packets in the data records. VALID_AACS_LRS_COUNT = xxx Total number of valid Attitude and Articulation Control System (AACS) Low Rate Science packets in the data records. GCF_ERRORS = xxx Total number of data records in the EDR file with Ground Communications Facility (GCF) block errors. NIMS_GOLAY_ERRORS = xxx Total number of data records in the EDR file containing NIMS LRS packets with possible Golay error. AACS_GOLAY_ERRORS = xxx Total number of data records in the EDR file containing AACS LRS packets with possible Golay error. TOTAL_GOLAY_ERRORS = xxx Total number of data records in the EDR file containing Golay errors. PSEUDO_NOISE_ERROR_FLAG = xxxxx Pseudo-noise number contained bit errors, spacecraft clock was corrected. Possible values are TRUE or FALSE. SPACECRAFT_CLOCK_ERROR_FLAG = xxxxx Spacecraft clock errors found, spacecraft clock was corrected. Possible values are TRUE or FALSE. CHECKSUM = xxxxxxxxxx The sum of all the bytes within the DATA_TABLE object. This parameter can be used to verify the reading of an EDR file. END_OBJECT = DATA_TABLE This element marks the end of the data table object. END This marks the end of the keywords for the label area. Bytes in the label area after the END statement are ignored. 10 - DATA PROCESSING CONSIDERATIONS Data Processing Systems for the NIMS EDR Data Collection ________________________________________________________ Galileo/NIMS data on this CD-ROM is in a raw Experiment Data Record (EDR) format which is difficult to use for science analysis. Unlike data from ordinary imaging instruments, which may be displayed directly as images (albeit uncalibrated ones), NIMS data is gathered in a complex fashion and must be restructured for convenient use. This CD-ROM contains several programs for examining these raw EDR format files. These programs are found in the SOFTWARE directory tree and documentation is provided by SOFTINFO.TXT files in that tree. VAX/VMS and SUN versions of these programs are present. The natural form of imaging spectrometer data is the spectral image cube. It is normally in band sequential format, but has a dual nature. It is a series of "images" of the target, each in a different wavelength, in ascending order. It is also a set of spectra, each at a particular line and sample, over the target area. Each spectrum describes a small portion of the target. When transformed into cubes, the data may be analyzed spatially, an image at a time, or spectrally, a spectrum at a time, or in more complex spatial-spectral fashion. Two sets of software exist to generate these cubes. One is part of the ISIS (Integrated Software for Imaging Spectrometers) system; the other is part of the Vicar (Video Image Communication and Retrieval) system. Both produce similar, but not identical, NIMS cubes. The differences are in the methods of binning data into a projected space, and in the selection of geometry and other items stored in backplanes of the cubes. Both software sets provide the option of radiometrically and photometrically calibrating the individual data values. Both sets produce cubes with PDS/ISIS labels, which can be read, displayed and analyzed by generic ISIS software. NIMS data from the various Galileo encounters will ultimately be processed into calibrated cubes, systematically by the Vicar software and selectively by the ISIS software. These cubes will be collected on CD-ROMs for distribution to the scientific community. ISIS consists primarily of programs which process, display and analyze data in cube format, data which may come from NIMS or from other imaging spectrometers. But it is also a programming environment, in which the NIMS-specific cube generation software mentioned above was developed. (It is also capable of handling data in "table" format, a capability that is also used in the cube generation software.) ISIS was initially developed using the VMS operating system on the DEC VAX series of computers. The high level processing capabilities of the ISIS system are currently being ported to the the UNIX/SUN environment and should be operational by calendar year 1994. Vicar is an image processing system with a long history, which has some multispectral capability, including the cube generation software mentioned above. It is presently available in both VAX/VMS and Unix versions. Various parameters are needed when generating spectral image cubes. In order to assist in this process, it is planned to include cube generation parameter files for all observations (including those whose EDRs are on this volume) in later volumes of the set. These files would allow the user to generate a cube of an observation automatically from the EDR(s) containing the data. Both ISIS and Vicar parameter files may be provided. For additional information on ISIS and Vicar system availability and related technical support, see "Whom to Contact for Information", section 11 of this document. 11 - WHOM TO CONTACT FOR INFORMATION For information pertaining to the content of this CD-ROM. --------------------------------------------------------- Bob Mehlman UCLA/IGPP Los Angeles, CA 90024-156704 (310) 825-2434 Span Mail : GRUMPY::RMEHLMAN ISSAC::RMEHLMAN NASAmail : RMEHLMAN Internet : rmehlman@uclasp.igpp.ucla.edu BITNET : RMEHLMAN@UCLASP Christopher E. Isbell PDS Imaging Node U.S. Geological Survey 2255 N. Gemini Flagstaff, AZ 86001 (602) 556-7210 Span Mail : ASTROG::CISBELL Internet : cisbell@astrog.span.nasa.gov cisbell@leonardo.wr.usgs.gov THE ISIS SYSTEM --------------- To obtain the VAX/VMS version of the ISIS system ------------------------------------------------ Elias Barbinis, NIMS Librarian Jet Propulsion Laboratory Mail stop 183-601 4800 Oak Grove Drive Pasadena, CA 91109 (818) 354-3214 NSI-Decnet : HAPPY::ISISMGR Internet : ebarbinis@issac.jpl.nasa.gov Technical questions on ISIS NIMS cube generation ------------------------------------------------ Bob Mehlman UCLA/IGPP Los Angeles, CA 90024 (310)825-2434 NSI-Decnet : GRUMPY::RMEHLMAN Internet : rmehlman@uclasp.igpp.ucla.edu Technical questions on generic ISIS capability ---------------------------------------------- James Torson U.S. Geological Survey 2255 N. Gemini Flagstaff, AZ 86001 (602) 556-7258 NSI-Decnet : ASTROG::JTORSON Internet : jtorson@astrog.span.nasa.gov THE VICAR SYSTEM ---------------- To obtain the Vicar system if you are associated with Galileo ------------------------------------------------------------- Lisa Wainio Jet Propulsion Laboratory Mail stop 168-514 4800 Oak Grove Drive Pasadena, CA 91109 (818) 354-5398 NSI-Decnet : MIPL3::LAW320 Internet : law320@mipl3.jpl.nasa.gov To obtain the Vicar system if you are NOT associated with Galileo --------------------------------------------------------- COSMIC University of Georgia 382 East Broad Street Athens, GA 30603 (706) 542-3265 Technical questions on Vicar NIMS cube generation ------------------------------------------------- Lucas Kamp Jet Propulsion Laboratory Mail stop 168-414 4800 Oak Grove Drive Pasadena, CA 91109 (818) 354-3214 NSI-Decnet : MIPL3::LWK059 Internet : lwk059@mipl3.jpl.nasa.gov ADDITIONAL INFORMATION ---------------------- Information about CD-ROM Hardware and Software and for general assistance in CD-ROM use. -------------------------------------------------- Data Distribution Laboratory MS 525-3610 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 (818) 306-6303 Electronic mail address: Internet: DDL@stargate.jpl.nasa.gov JPL's Data Distribution Lab has produced "Catalog of Scientific CD-ROM Publications". This document describes the Planetary CD-ROM collections and the various CD-ROM titles produced by government agencies. It also identifies software which is available for displaying and processing these data sets. The catalog can be ordered from: PDS Operator MS 525-3610 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 (818) 306-6130 Electronic mail address: NSI/DECnet:JPLPDS::PDS_OPERATOR Information about other PDS Data Products can also be obtained from the PDS Operator listed above. 12 - ACKNOWLEDGEMENTS The National Aeronautics and Space Administration is charged with the responsibility for coordination of a program of systematic exploration of the planets by U.S. spacecraft. To this end, it finances spaceflight missions and data analysis and research programs administered and performed by numerous institutions. These include the Galileo NIMS project, the University of California at Los Angeles and the Planetary Data System which involves the U.S. Geological Survey and Jet Propulsion Laboratory. For specific personal contacts in regards to this CD-ROM, see "Whom to Contact for Information", section 11 of this document. 13 - REFERENCES 1. R. W. Carlson, P. R. Weissman, W. E. Smythe, J. C. Mahoney, and the NIMS Science and Engineering Teams, "Near-Infrared Mapping Spectrometer Experiment on Galileo", Space Science Reviews 60, 457-502, 1992. [This volume also contains papers describing the other Galileo instruments.] 2. Irving M. Aptaker, "A near-infrared mapping spectrometer for investigation of Jupiter and its satellites", SPIE 331 ("Instrumentation in Astronomy IV") IV", 182-196, 1982. 3. R. W. Carlson, "Spectral mapping of Jupiter and the Galilean satellites in the near infrared", SPIE 268 ("Imaging Spectroscopy"), 29-34, 1981. 4. R. W. Carlson et al, "Galileo Infrared Imaging Spectroscopy Measurements at Venus", Science, 253, 1541-1548, 27 September 1991. [This issue of Science also contains papers describing Venus data taken by the other Galileo instruments.] 5. Zamani, P., "Project Galileo Software Interface Specification: NIMS Experiment Data Record", 625-610: SIS 232-08 (JPL D-296), July 30, 1991. 6. Planetary Data Systems Standards Reference, (1992), JPL D-7669. Distributed by the Planetary Data System, Jet Propulsion Laboratory. 7. Planetary Science Data Dictionary Document, (1992), JPL D-7116. Distributed by the Planetary Data System, Jet Propulsion Laboratory. 8. Planetary Data System, April (1993), Planetary Data System Data Preparation Workbook, JPL Document D-7669, Part 1, Version 3.0. Distributed by the Planetary Data System, Jet Propulsion Laboratory. 9. Planetary Data System, May (1991), Planetary Data System Data Preparation Workbook - Volume 2, Standards, JPL Document D-7669, Version 2.0. Distributed by the Planetary Data System, Jet Propulsion Laboratory.