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PDS_VERSION_ID                    = PDS3                                      
RECORD_TYPE                       = FIXED_LENGTH                              
RECORD_BYTES                      = 80                                        
                                                                              
OBJECT                            = DATA_SET                                  
 DATA_SET_ID                      = "GO-JS-RSS-1-TDF-V1.0"                    
                                                                              
 OBJECT                           = DATA_SET_INFORMATION                      
  DATA_SET_NAME                   = "GALILEO RADIO TRACKING SATELLITE         
                                    OCCULTATION MEASUREMENT EXPERIMENT        
                                    DATA V1.0"                                
  DATA_SET_COLLECTION_MEMBER_FLG  = "N"                                       
  DATA_OBJECT_TYPE                = TABLE                                     
  START_TIME                      = 1996-12-19T06:59:00Z                      
  STOP_TIME                       = 1997-08-03T23:10:00Z                      
  DATA_SET_RELEASE_DATE           = 1999-04-30                                
  PRODUCER_FULL_NAME              = "RADIO SCIENCE SUPPORT TEAM"              
  DETAILED_CATALOG_FLAG           = "N"                                       
  DATA_SET_DESC                   = "                                         
                                                                              
Data Set Overview                                                             
    =================                                                         
                                                                              
      This data set contains raw radio tracking data from the                 
      Galileo (GLL) Satellite Occultation Measurement Experiment.             
      The experiment were conducted over the following time period:           
                                                                              
         December 18, 1995 to August 3, 1997                                  
                                                                              
                                                                              
      The data set includes NASA Deep Space Network (DSN) Archival            
      Tracking Data Files (ATDFs or TDFs) and/or Orbit Data Files (ODFs)      
      and other data used primarily for Galileo navigation, science probing   
      of gravitational fields and waves, and ephemeris development.           
                                                                              
      The experiment is described in detail in DESCRIPT.TXT in the DOCUMENT   
      directory.  Another explanation of the experiment, as well as the       
      ground equipment, spacecraft, and operations procedures, may be found   
      in the Radio Science Handbook.  This handbook is also in the DOCUMENT   
      directory.                                                              
                                                                              
    Parameters                                                                
    ==========                                                                
      Each 288-byte ATDF data record contains 117 parameters, stored at       
      at rates of up to 10 records per second.  The parameters include        
      outputs from the DSN ranging system, estimates of Doppler offsets,      
      estimates of received signal strength, and status information on        
      components of the DSN system.  The ATDF is described by a Software      
      Interface Specification (SIS), included as TRK_2_25.TXT in the          
      DOCUMENT directory of each archival volume.                             
                                                                              
      Each 36-byte ODF data record contains 22 parameters which may include   
      outputs from the DSN ranging system, estimates of Doppler offsets,      
      and 'footprint' information.  The ODF is described by a Software        
      Interface Specification (SIS), included as TRK_2_18.TXT in the          
      DOCUMENT directory of each archival volume.                             
                                                                              
                                                                              
    Processing                                                                
    ==========                                                                
      Radiometric data are received by the DSN Network Operations and Control 
      Center (NOCC) Navigation Subsystem (NAV) in the form of Intermediate    
      Data Records (IDRs).  These IDRs are processed to generate ATDFs.  An   
      ATDF contains all radiometric data received from the Deep Space         
      Communications Complexes (DSSCs) tracking a single spacecraft for one   
      or more passes or days.                                                 
                                                                              
      The ODF is produced from IDRs by the NOCC NAV; it contains far fewer    
      fields than the ATDF and is preferred by investigators in certain       
      applications because of its smaller volume (compared with the ATDF).    
                                                                              
                                                                              
    Data                                                                      
    ====                                                                      
      ATDFs and ODFs contain precise radio range and Doppler measurements     
      made between DSN ground stations and a spacecraft.  During the Galileo  
      Venus encounter, for example, coded waveforms were transmitted from     
      the Earth, relayed by the on-board Galileo telecommunications system,   
      and received back on Earth.  Cross correlation between the transmitted  
      and received waveforms yielded a measurement of the round trip          
      distance, which could then be related to the Earth-Venus distance       
      during the flyby.  Doppler shift from the same measurements could be    
      interpreted as relative velocity along the propagation path.            
                                                                              
      An ATDF has a file name of the form  ydddeeeX.TDF  where  y  is         
      the least significant digit of the year and  ddd  is the day-of-year    
      for the first ATDF record.  The  eee  gives day-of-year for the last    
      data record in the ATDF, and  X  is set to  'A'.                        
                                                                              
      Each ATDF is accompanied by a full PDS detached label with name         
      ydddeeeX.LBL  which completely describes the contents of the ATDF.      
      The format and contents are also described in TRK_2_25.TXT in the       
      DOCUMENT directory of each archival volume.  Both the ATDF and its      
      label are stored in the TDF directory of an archival volume.            
                                                                              
      An ODF has a file name of the form  ydddeeeX.ODF  where the components  
      of the file name are explained above.  Each ODF is accompanied by a     
      full PDS label with name  ydddeeeX.LBL.  Both the ODF and its label     
      are stored in the ODF directory of an archival volume.                  
                                                                              
                                                                              
    Ancillary Data                                                            
    ==============                                                            
                                                                              
      The ancillary files are stored in the CALIB, GEOMETRY and DOCUMENT      
      directories.  Each ancillary file is accompanied by a detached PDS      
      minimal label having the same file name except for the suffix 'LBL'.    
                                                                              
      Low-Gain Antenna (LGA) Radiation Pattern                                
      -----------------------------------------                               
        The radiation pattern of the low-gain antenna (LGA) is described      
        in files LGA1_DL.TAB and LGA1_UL.TAB in the CALIB directory.          
        These files provide the radiation patterns for downlink and           
        uplink, respectively.                                                 
                                                                              
      Spacecraft Ephemeris Information                                        
      --------------------------------                                        
        The spacecraft ephemeris information is located in the GEOMETRY       
        directory.  The S980326B.XSP file is the reconstructed SP kernel      
        for the Cruise portion of the Galileo mission and includes the        
        Satellite Occultation Measurement Experiment.                         
                                                                              
        There is also a file containing right ascension and declination       
        information for the spacecraft at midnight for each day of the        
        experiment.  This file is also in the GEOMETRY directory, and it is   
        called RA_DEC.TAB.                                                    
                                                                              
    Coordinate System                                                         
    =================                                                         
      Most data types are not dependent on definition of a coordinate         
      system; for those that are, the user should consult the appropriate     
      SIS for information.                                                    
                                                                              
                                                                              
    Software                                                                  
    ========                                                                  
      Software for parsing, reducing, and analyzing data such as these has    
      been developed at the Jet Propulsion Laboratory and elsewhere.          
      Because parsing must be done at the bit level, its implementation may   
      be very sensitive to platform and operating system.  No parsing         
      has been written and tested on a variety of platforms, so none has      
      been included with the archival data set.  Users are referred to PDS    
      labels, to files in the DOCUMENT directory, and to hard copy Software   
      Interface Specifications for detailed information on file formats.      
                                                                              
                                                                              
    Media/Format                                                              
    ============                                                              
      The archival data set is written on CD-WO media using the Young Minds   
      CD Studio authoring system.  The CD-WO volume conforms to ISO 9660      
      standards."                                                             
                                                                              
                                                                              
  CONFIDENCE_LEVEL_NOTE           = "                                         
                                                                              
    Overview                                                                  
    ========                                                                  
      There are no known limitations to use of these data, subject to         
      signal-to-noise considerations which would be typical for systems       
      of this type.                                                           
                                                                              
                                                                              
    Review                                                                    
    ======                                                                    
     Prior to creation of the final version of the archival data set,         
     key elements of the archive were distributed for preliminary review.     
     These included electronic versions of example PDS labels, CATALOG        
     files, and Software Interface Specifications.  These materials were      
     distributed to PDS personnel and the PDS Radio Science advisor.          
                                                                              
                                                                              
    Data Coverage and Quality                                                 
    =========================                                                 
     The data covers the periods of Satellite Occultation Measurement         
     Experiment between December 18, 1996 and August  3, 1977.                
     There are no quality issues which would limit use of this data           
     other than the normal signal-to-noise constraints.                       
                                                                              
                                                                              
    Limitations                                                               
    ===========                                                               
      None."                                                                  
                                                                              
                                                                              
 END_OBJECT                       = DATA_SET_INFORMATION                      
                                                                              
 OBJECT                           = DATA_SET_TARGET                           
  TARGET_NAME                     = UNK                                       
 END_OBJECT                       = DATA_SET_TARGET                           
                                                                              
 OBJECT                           = DATA_SET_HOST                             
  INSTRUMENT_HOST_ID              = GO                                        
  INSTRUMENT_ID                   = RSS                                       
 END_OBJECT                       = DATA_SET_HOST                             
                                                                              
 OBJECT                           = DATA_SET_REFERENCE_INFORMATION            
  REFERENCE_KEY_ID                = "HOWARDETAL1992"                          
 END_OBJECT                       = DATA_SET_REFERENCE_INFORMATION            
                                                                              
END_OBJECT                        = DATA_SET                                  
                                                                              
END