PDS_VERSION_ID      = PDS3                                                    
LABEL_REVISION_NOTE = "                                                       
  2012-02-15  SBN:T.Barnes       Created to resolve lien.                     
  2012-04-14  SBN:sam            Corrected COMET_NAMEs 55P/Tempel-Tuttle 1,   
    160P/LINEAR 43, C/Great September Comet, and C/Utsunomiya.                
  2012-04-17  SBN:sam            Corrected PRODUCT_NAME, which was identical  
    to the value in comet.lbl.                                                
  "                                                                           
                                                                              
RECORD_TYPE  = "FIXED_LENGTH"                                                 
RECORD_BYTES = 63                                                             
FILE_RECORDS = 164                                                            
                                                                              
^TABLE  = "BEST_RADII.TAB"                                                    
                                                                              
DATA_SET_ID           = "EAR-C-COMPIL-5-COMET-NUC-PROPERTIES-V2.0"            
PRODUCT_ID            = "BEST_RADII.TAB"                                      
PRODUCT_NAME          = "BEST RADII FOR COMET NUCLEI"                         
PRODUCT_CREATION_TIME = 2012-02-15                                            
                                                                              
TARGET_NAME           = "COMET"                                               
INSTRUMENT_HOST_NAME  = "PUBLISHED LITERATURE"                                
INSTRUMENT_NAME       = "COMPILATION"                                         
START_TIME            = "UNK"                                                 
STOP_TIME             = 2012-02-15T00:00:00.000                               
                                                                              
DESCRIPTION           = "                                                     
  This file contains a table containing the current 'best value', according   
  to Michael A'Hearn, of the radius of the comet nucleus.                     
  "                                                                           
                                                                              
OBJECT     = TABLE                                                            
  NAME               = "BEST_COMET_RADII"                                     
  INTERCHANGE_FORMAT = "ASCII"                                                
  COLUMNS            = 7                                                      
  ROW_BYTES          = 63                                                     
  ROWS               = 164                                                    
  DESCRIPTION        = "                                                      
    This table contains the currently 'best' available value, according to    
    Michael A'Hearn, of the spherical volume radius (in the case of existing  
    shape models) or the rough maximum cross section radius or another        
    'best value' radius for each comet's nucleus.                             
    "                                                                         
                                                                              
  OBJECT     = COLUMN                                                         
    COLUMN_NUMBER    = 1                                                      
    NAME             = "PERIODIC_NUMBER"                                      
    START_BYTE       = 1                                                      
    BYTES            = 3                                                      
    DATA_TYPE        = "ASCII_INTEGER"                                        
    FORMAT           = "I3"                                                   
    MISSING_CONSTANT = " "                                                    
    DESCRIPTION      = "Periodic number of the comet, if any."                
  END_OBJECT = COLUMN                                                         
                                                                              
  OBJECT     = COLUMN                                                         
    COLUMN_NUMBER    = 2                                                      
    NAME             = "COMET_TYPE"                                           
    START_BYTE       = 4                                                      
    BYTES            = 1                                                      
    DATA_TYPE        = "CHARACTER"                                            
    FORMAT           = "A1"                                                   
    DESCRIPTION      = "A single character indicating the object type:        
      P = periodic comet; C = non-periodic comet; D = defunct comet.          
      (believed to have disintegrated)"                                       
  END_OBJECT = COLUMN                                                         
                                                                              
  OBJECT     = COLUMN                                                         
    COLUMN_NUMBER    = 3                                                      
    NAME             = "COMET_NAME"                                           
    START_BYTE       = 6                                                      
    BYTES            = 23                                                     
    DATA_TYPE        = "CHARACTER"                                            
    FORMAT           = "A23"                                                  
    DESCRIPTION      = "Name of the comet"                                    
  END_OBJECT = COLUMN                                                         
                                                                              
  OBJECT     = COLUMN                                                         
    COLUMN_NUMBER    = 4                                                      
    NAME             = "DISCOVERY_ID"                                         
    START_BYTE       = 31                                                     
    BYTES            = 10                                                     
    DATA_TYPE        = "CHARACTER"                                            
    FORMAT           = "A10"                                                  
    MISSING_CONSTANT = " "                                                    
    DESCRIPTION      = "Discovery ID assigned by the MPC.  These are provided 
      only for unnumbered comets.  This may be an asteroid ID if the comet    
      was not obviously active when first discovered."                        
  END_OBJECT = COLUMN                                                         
                                                                              
  OBJECT     = COLUMN                                                         
    COLUMN_NUMBER    = 5                                                      
    NAME             = "COMET_CLASS"                                          
    START_BYTE       = 43                                                     
    BYTES            = 3                                                      
    DATA_TYPE        = "CHARACTER"                                            
    FORMAT           = "A3"                                                   
    DESCRIPTION      = "Dynamic classification of the comet: either 'EC', for 
      ecliptic comets; or 'NIC' for nearly-isotropic comets.                  
                                                                              
      If T[j] is the Tisserand parameter with respect to Jupiter, then        
      ecliptic comets (EC) are those with 2 <= T[j] <= 3 and a period of      
      less than about 20 year.  Nearly isotropic comets (NIC) are those       
      with T[j] < 2.                                                          
      "                                                                       
  END_OBJECT = COLUMN                                                         
                                                                              
  OBJECT     = COLUMN                                                         
    COLUMN_NUMBER    = 6                                                      
    NAME             = "TISSERAND_JUPITER"                                    
    START_BYTE       = 47                                                     
    BYTES            = 6                                                      
    DATA_TYPE        = "ASCII_REAL"                                           
    FORMAT           = "F6.2"                                                 
    MISSING_CONSTANT = -99.99                                                 
    DESCRIPTION      = "Tisserand invariant parameter with respect to Jupiter.
      Rounded value calculated using most recent data as reported in          
      Marsden and Williams (2008).  Value only to be used as an estimation."  
  END_OBJECT = COLUMN                                                         
                                                                              
  OBJECT     = COLUMN                                                         
    COLUMN_NUMBER    = 7                                                      
    NAME             = "BEST_RADIUS"                                          
    START_BYTE       = 57                                                     
    BYTES            = 5                                                      
    DATA_TYPE        = "ASCII_REAL"                                           
    FORMAT           = "F5.2"                                                 
    UNIT             = "KILOMETER"                                            
    MISSING_CONSTANT = -.99                                                   
    DESCRIPTION      = "Spherical radius of comet nuclues' volume."           
  END_OBJECT = COLUMN                                                         
                                                                              
END_OBJECT = TABLE                                                            
                                                                              
END