PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT INTERCHANGE_FORMAT = ASCII PUBLICATION_DATE = 2008-12-03 NOTE = "SCL-Kernel Information" END_OBJECT = TEXT END General Information About SPICE SCL-Kernels =========================================== In the SPICE system, Spacecraft Clock (or SCL) -kernel contains a set of information required to perform a mapping between Ephemeris time (ET) and spacecraft on-board time (SCLK). The spacecraft clock coefficient information contained in SCLK file can be manipulated using the SPICE Toolkit APIs, calls to which can be integrated into user application programs. The information regarding how to obtain the SPICE system toolkit for a number of languages and computer platforms is located in the ``/software'' subdirectory of the main directory of this data set. Refer to the ``sclk.req'' document provided with the toolkit to get more information about conversion between ET and spacecraft clock times. Viking Orbiter SCL-kernels Contained in This Data Set ===================================================== This data set contains the following VO1 and VO2 SCLK files (only name portion of the file name is shown; the extension of all SCLK file names is ``.tsc''): vo1_fict VO1 SCLK file that was used in VO1 CK files generation. This SCLK file does NOT represent real Viking Orbiter 1 on-board clock but rather just count milliseconds since some initial epoch. vo2_fict VO2 SCLK file that was used in VO2 CK files generation. This SCLK file does NOT represent real Viking Orbiter 2 on-board clock but rather just count milliseconds since some initial epoch. vo1_fsc VO1 SCLK file containing linear piecewise function representing VO1 FSC on-board clock. This function was generated during VO1 image time tags restoration process. vo2_fsc VO2 SCLK file containing linear piecewise function representing VO2 FSC on-board clock. This function was generated during VO2 image time tags restoration process. Kernel File Details =================== The most detailed description of the data in an SCLK file is provided in metadata included inside the description area of the file. This information can be viewed using any text editor program. Refer to the ``vo_trec.txt'' document located in the ``document'' directory of this volume for more information regarding VO image time tags restoration performed by NAIF. Contact Information =================== Regarding VO project specific information provided in this data set and for general information about SPICE system: Charles H. Acton, Jr, (818)-354-3869, Chuck.Acton@jpl.nasa.gov, or Boris Semenov (818)-354-8136 Boris.Semenov@jpl.nasa.gov address: Navigation and Ancillary Information Facility (NAIF) Jet Propulsion Laboratory MS 301-125L 4800 Oak Grove Drive Pasadena CA 91109 USA