=============================================================================   
ROSETTA SCLK Files                                                              
=============================================================================   
                                                                                
  This "aareadme.txt" file describes the contents of the KERNELS/SCLK           
  directory of the ROSETTA SPICE data server. It also provides the file         
  naming conventions used for the ROSETTA SCLK kernels, and it provides         
  identification of the most current version of SCLK files.                     
                                                                                
  SCLK files are created from the information contained in the ESOC's DDID      
  Time Correlation Packets.                                                     
                                                                                
  All SCLK files (*.TSC) contained in this directory are unix text files.       
  These may be used in a non-compatible text environment by using               
  the ASCII mode of FTP to port the files.  [Ref 4b]                            
                                                                                
  Contact Jose Luis Vazquez (jlvazquez@sciops.esa.int) or Dave Heather          
  (dheather@rssd.esa.int) if you have any questions.                            
                                                                                
                                                                                
=============================================================================   
References                                                                      
=============================================================================   
    1. Data Delivery Interface Document (DDID)   Issue B5 (MEX-ESC-IF-5003)     
       27 Mar 2003                                                              
                                                                                
    2. SCLK Required Reading. NAIF Document No. 222.02  06 Oct 1999             
                                                                                
    3. Auxiliary Data Conversion into SPICE Kernels and Distribution.           
       (MEX-EST-PL-10210)                                                       
                                                                                
    4. Selected SPICE Tutorials from the NAIF server:                           
ftp://naif.jpl.nasa.gov/pub/naif/toolkit_docs/Tutorials/office/individual_docs/ 
                                                                                
       a) SCLK Tutorial               13_lsk_and_sclk.ppt                       
       b) Porting Kernels Tutorial    09_porting_kernels.ppt                    
                                                                                
                                                                                
                                                                                
=============================================================================   
Rosetta SCLK Directory Structure                                                
=============================================================================   
 aareadme.txt        Text file describing the directory structure, the naming   
                     conventions for the SCLKs, and the current version(s) of   
                     each SCLK type.                                            
                                                                                
 former_versions     Subdirectory that contains obsolete versions of the        
                     SCLK files that have been updated in the Current SCLK      
                     Kernels Set, and fake SCLK files used before the creation  
                     of real ones.                                              
                                                                                
                                                                                
=============================================================================   
Rosetta Spacecraft SCLK Naming Covention            ROS_yymmdd_[spec].TSC       
=============================================================================   
                                                                                
                                                                                
          token           description                                           
          ------------    --------------------------------------------------    
           yymmdd         File release date.                                    
           [spec]         Data type specification Identifier:                   
                             STEP   -- real SCLK files                          
                             FAKE   -- special fake SCLK files                  
                                                                                
=============================================================================   
Current SCLK Kernels Set                                                        
=============================================================================   
                                                                                
 Name                   Comments                                                
 -------------------    -----------------------------------------------------   
 ROS_yymmdd_STEP.TSC    This file is a SPICE spacecraft clock (SCLK) kernel     
                        containing information required for Rosetta spacecraft  
                        on-board clock to UTC conversion. This file provides    
                        the same time information that the Time Correlation     
                        packets released via DDS, with the exception of 60      
                        seconds before the starting time of each packet,        
                        during which the clock rate was sightly adjusted to     
                        make the correlation function continuous. For further   
                        discussion in this topic see [Ref 3]. This file was     
                        released on yy-mm-dd. This is the kernel to be used     
                        with the nominal attitude files (RATT, ATNR).           
                                                                                
 ros_triv.tsc           Trivial clock kernel (SCLK) for the Rosetta spacecraft, 
                        assuming an absolutely constant clock rate. Note        
                        that this is the kernel to be used with the RATM        
                        attitude files.                                         
                                                                                
                                                                                
-------------------                                                             
                                                                                
        This file was last modified on Sep. 9, 2014 (J. Vazquez)