MEX SCLK Files ============== This "aareadme.txt" file describes the contents of the kernels/sclk directory of the MEX SPICE data server. It also provides the file naming conventions used for the MEX 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, by the ADCS system located at ESAC. 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. At least a basic knowledge of the SPICE system is needed in order to use this kernel. The SPICE toolkit provides versions in Fortran (SPICELIB), C (CSPICE), IDL (icy) and Matlab (mice), and the user can choose any one that suits him/her. The SPICELIB routine FURNSH, CSPICE function furnsh_c, and icy and mice routine cspice_furnsh load a kernel file into the kernel pool as shown below. CALL FURNSH ( 'kernel_name' ) furnsh_c ( "kernel_name" ); cspice_furnsh, 'kernel_name' cspice_furnsh( 'kernel_name' ) In the case when two or more files contain data overlapping in time for a given object, for binary kernels, the file loaded last takes precedence. If two (or more) text kernels assign value(s) using the '=' operator to identical keywords, the data value(s) associated with the last loaded occurrence of the keyword are used -all earlier values have been replaced with the last loaded value(s). 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. Contact ESA SPICE Team esa_spice@sciops.esa.int , or Jose Luis Vazquez jlvazquez@sciops.esa.int if you have any questions. References ========== 1. Data Delivery Interface Document (DDID) Issue C1 (MEX-ESC-IF-5003) 1 July 2005 2. SCLK Required Reading (NAIF Document). All the NAIF Documents are available at the NAIF web: http://naif.jpl.nasa.gov Mars Express 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. MEX_yymmdd_STEP.TSC This file is a SPICE spacecraft clock (SCLK) kernel containing information required for MEX 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 yymmdd. ------------------- This file was last modified on March 4th, 2009. (J. Vazquez)