============================================================================= 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)