PDS_VERSION_ID = PDS3                                                         
                                                                              
RECORD_TYPE    = "STREAM"                                                     
                                                                              
OBJECT     = TEXT                                                             
  PUBLICATION_DATE = 2011-05-17                                               
  NOTE             = "INDEX/ directory contents"                              
END_OBJECT = TEXT                                                             
END                                                                           
                                                                              
INDEX/ Directory Contents                                                     
=========================                                                     
This directory contains indices into the files on this disk.                  
                                                                              
  checksum.lbl     PDS3 label for checksum.tab                                
  checksum.tab     MD5 checksums for every file on the disk except            
                   itself and checksum.lbl                                    
  index.lbl        PDS3 label for index.tab                                   
  index.tab        The required PDS manifest index                            
  indxinfo.txt     This file                                                  
  nettabinfo.txt   A description of the IHW "NETABLES" index files, below     
                                                                              
                                                                              
These files comprise the original Amateur Observations Net index for the      
observations included in "The Comet Halley Archive Summary Volume"            
[JPL D-400-450]:                                                              
                                                                              
  am_vis.dbf                                                                  
  am_vis.hdr                                                                  
  am_vis.idx                                                                  
  am_vis.lbl                                                                  
  am_vis.str                                                                  
                                                                              
These files list the values of most of the FITS keywords used in the          
Amateur Observations Net visual magnitude estimate submissions:               
                                                                              
  netamatv.dbf                                                                
  netamatv.hdr                                                                
  netamatv.idx                                                                
  netamatv.lbl                                                                
  netamatv.str                                                                
                                                                              
The various file types are described in "nettabinfo.txt".  This index is      
very useful for finding specific files based on IHW keywords, but note that   
the directory structure on this disk is similar but not identical to the      
structure on the original HAL_0019-23 disks.  The DATA/ directory on this     
disk is strictly divided by year/month/day, which may make for some very      
long directory listings on peak observation days.                             
                                                                              
In the case of this data set, which includes none of the non-digitized        
data, the above .IDX files provide a summary of the pertinent information     
in the null-data labels.