Description of the TNO AND CENTAUR COLORS bundle V1.0
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Bundle Generation Date: 2020-02-28
Peer Review: 2014 Asteroid Review, Fri May 16 00:00:00 MST 2014               
Discipline node: Small Bodies Node


Content description based on the data set catalog file description for the PDS3 version, EAR-A-COMPIL-3-TNO-CEN-COLOR-V10.0
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Note: for PDS3 data sets migrated to PDS4, the following text is taken
verbatim from the data set description and confidence level note of the
PDS3 data set catalog file. In these cases, some details may not be correct
as a description of the PDS4 bundle.
                                                           
                                                                              
  This data set is intended to include published broadband colors of centaurs 
  and Transneptunian Objects (TNOs) published through March 2014.  It also    
  includes some comets with Centaur orbits.                                   
                                                                              
  Data                                                                        
  ====                                                                        
                                                                              
  Data were collected from the published literature and include               
  Johnson-Kron-Cousins color indices and one-sigma uncertainty values.  Many  
  objects have data reported by several groups.  Details of the observations  
  and data reduction are to be found in the individual papers.  Note that only
  UBVRIJHK colors are included in this collection.  For ECAS colors of Centaur
  2060 Chiron, see the PDS ECAS data set, EAR-A-2CP-3-RDR-ECAS-V4.0.          
                                                                              
  Results on objects with comet designations are provided in a separate file, 
  cometcencol.tab.                                                            
                                                                              
  Archiving History                                                           
  =================                                                           
                                                                              
  The TNO colors data set, EAR-A-3-RDR-TNO-PHOT, was first introduced in 2000 
  and has been updated mostly annually since then.  At the 2004 review, a data
  set compiling colors of Centaurs was also introduced, and it was decided to 
  combine the two to make a new data set.  A column was added to the data     
  table to indicate whether the object is a TNO or a Centaur.  In the 2009    
  update, a column was added to specify if the measurement was made of the    
  primary or secondary, or of the coma or nucleus, of the target body.  In    
  2010, the column identifying the dynamic classification (TNO or CEN) was    
  changed to reflect the classification by the MPC (TNO or CEN/SDO) rather    
  than the assignment made by the individual publication, as it had been in   
  earlier versions of the data set.                                           
                                                                              
  This data set supersedes all the versions of the TNO colors data set,       
  EAR-A-3-RDR-TNO-PHOT.


Known issues or problems with the data
======================================

    We assume the R-bandpass used by the various observers is in the          
    Kron-Cousins system, but that this cannot be verified for all of the      
    measurements included in this data set.                                   
                                                                              
    Some entries provide colors which result from the combination of multiple 
    observing runs, sometimes over several years.  These results have no      
    single observing date.  For asteroids, these results are provided in a    
    separate file, multirun.tab, to discourage their inappropriate use.  For  
    cometary objects, these results are provided in the comet file,           
    cometcencol.tab, with a null value of 9999-99-99 for the observing date.  
    (The comet file is so short this is unlikely to result in confusion.)  See
    the original papers for information about the observing dates for these   
    results.                                                                  
                                                                              
    Refer to the individual published papers for the confidence level of any  
    individual measurement.

PDS3 Source
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Version 1.0 of this bundle was migrated from version 10.0 of the PDS3 data set EAR-A-COMPIL-3-TNO-CEN-COLOR-V10.0.