DAWN SCLK files.
===========================================================================
 
     This ``aareadme.txt'' file describes contents of the kernels/sclk
     directory of the DAWN SPICE data server. It was last modified on
     December 20, 2007. Contact Chuck Acton (818-354-3869,
     Chuck.Acton@jpl.nasa.gov) or Boris Semenov (818-354-8136,
     Boris.Semenov@jpl.nasa.gov) if you have any questions regarding this
     data.
 
 
Brief summary
--------------------------------------------------------
 
     This directory contains the SPICE SCL-Kernel files for the DAWN
     spacecraft on-board clock. All files are in IEEE text format and must
     be copied using ftp ASCII transfer to any non-UNIX workstation. The
     following files are present in this directory. (Only file names are
     shown; the file name extensions of the text SCLK files are always
     ``.tsc''):
 
           DAWN_203_SCLKSCET_VVVVV    ``Actual'' DAWN Spacecraft clock
                                      coefficients Kernel (SCLK) file(s),
                                      providing DAWN on-board clock
                                      correlation based on time correlation
                                      data from telemetry.
 
           DAWN_203_PSCLKSCET_VVVVV   ``Nominal'' DAWN Spacecraft clock
                                      coefficients Kernel (SCLK) file,
                                      providing DAWN on-board clock
                                      correlation based on the assumption
                                      that the clock runs synchronously
                                      with TDT.
 
     Both types of files are generated by converting corresponding
     SCLKvSCET files produced by DSMS Time Service to SPICE SCLK format
     using MAKCLK SPICE Utility program. These files are created/delivered
     every time when a new SCLKvSCET file is delivered (usually once every
     two-four weeks for the actual SCLK files and once at the beginning of
     the mission for nominal SCLK files.)
 
     If multiple versions of an SCLK file are provided, always use the
     latest version (unless earlier version is needed for some special
     reasons.)