PDS_VERSION_ID      = PDS3                                                    
RECORD_TYPE         = "STREAM"                                                
LABEL_REVISION_NOTE = "                                                       
  2007-12-11 SBN:McLaughlin Added data set ID for this doc set;               
"                                                                             
                                                                              
DATA_SET_ID         = { "DI-C-HRII/HRIV/MRI/ITS-6-DOC-SET-V1.0",              
                        "DIF-C-HRII-2-9P-ENCOUNTER-V1.0",                     
                        "DIF-C-HRIV-2-9P-ENCOUNTER-V1.0",                     
                        "DIF-C-HRII-3/4-9P-ENCOUNTER-V1.0",                   
                        "DIF-C-HRIV-3/4-9P-ENCOUNTER-V1.0",                   
                        "DIF-C-HRII-3/4-9P-ENCOUNTER-V2.0",                   
                        "DIF-C-HRIV-3/4-9P-ENCOUNTER-V2.0" }                  
                                                                              
^ASCII_DOCUMENT     = "LOOKBACK_CONTEXT_IMAGE_LOG.ASC"                        
                                                                              
OBJECT                = ASCII_DOCUMENT                                        
  DOCUMENT_NAME       = "Log of Parameters for Generating HRIV Context Images 
    for HRII Lookback Data"                                                   
  DOCUMENT_TOPIC_TYPE = "DATA ANALYSIS"                                       
  INTERCHANGE_FORMAT  = "ASCII"                                               
  DOCUMENT_FORMAT     = "TEXT"                                                
  DESCRIPTION         = "This document is a log of the parameters used to     
    generate the HRIV context images for HRII data taken during the lookback, 
    after impact, at comet 9P/Tempel 1  The log begins with HRII exposure     
    9010000_001, a staring frame starting at UTC 2005-07-04T06:28:37.         
    The last exposure in the log is 9010009_004, which ended at UTC           
    2005-07-04T06:59:47.  This log was created by Steve Collins, a member     
    of the Deep Impact Navigation team at JPL.  To preserve the column        
    associations for easier re-ingestion into a spreadsheet application,      
    the ASCII version of this document is provided in CSV format.  The        
    first record in the log identifies each column.  A description of each    
    column is provided here:                                                  
                                                                              
    - Obs_instr, obs_expid, obs_image_num, and obs_image_mode give a          
      description of the HRII observation                                     
    - Obs_range gives the range to the impact site at the epoch of            
      the HRII observation                                                    
    - Context_instr, context_expid, context_image_num, and context_image_mode 
      give a description of the HRIV context image                            
    - Context_range gives the range to the impact site at the epoch of        
      HRIV context image                                                      
    - Ir1_x, ir1_y, ir2_x, and ir2_y give the estimated position of           
      each end of the observation image IR slit in the HRIV context           
      image.  This the context image is displayed with lines samples          
      increasing to the right and and lines increasing to the top (up).       
    - HRI_ctr_x and HRI_ctr_y give the center of the HRII frame in the        
      HRIV context image. This assumes the context image is displayed         
      with lines samples increasing to the right and and lines increasing     
      to the top (up).                                                        
    - Impactsite_x and impactsite_y give the estimated position of the        
      impact site in the context image.  This is computed from the            
      interpolated attitude telemetry at the context-image epoch, and         
      the reconstructed ephemeris (Deep_Impact_flyby-Heliocenter2.bsp)        
      using the spacecraft clock to ephemeris time conversion from the        
      dif_sclkscet_00015_science.tsc SPICE kernel.  No information from       
      the HRII observation image is used in this computation.  The            
      value for impactsite_x and impactsite_y assume the context image        
      is displayed with lines samples increasing to the right and and         
      lines increasing to the top (up).  For lookback frames, the location    
      of the impact site was still calculated although the location was       
      on the far side of the nucleus; the impact site circle should be        
      ignored for these frames.                                               
    - HRIfovsize gives the size of the observation-image HRI frame in         
      the HRIV context image.  Values are given in context-image pixels.      
    "                                                                         
  PUBLICATION_DATE    = 2007-01-29                                            
END_OBJECT            = ASCII_DOCUMENT                                        
                                                                              
END