=============================================================================   
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 Marc Costa Sitja (mcosta@sciops.esa.int) or the ESA SPICE Service 
  (esa_spice@sciops.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. This file was released 
                        on yy-mm-dd. This is the kernel to be used 
                        with the nominal attitude files (RATT, ATNR).

 LANDER_yymmdd_STEP.TSC This file is a SPICE spacecraft clock (SCLK) 
                        kernel containing information required for 
                        Rosetta lander 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. This file was generated 
                        on yy-mm-dd. This is the kernel to be used 
                        with the nominal attitude files (LATT).                        

                                                                                
 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. 14, 2017 (M. Costa)                
                                                                                
                                                                                
End of aareadme file.