KPL/SCLK WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING This SCLK provides MSL LMST for the landing site at the JPL Mars yard. It must be used only for testing applications and never for flight ops tasks. WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING MSL SCLK File Implementing LMST at JPL Mars Yard =========================================================================== This file is a SPICE spacecraft clock (SCLK) kernel implementing Local Mean Solar Time (LMST). This file contains information required to convert between Ephemeris Time (ET) and LMST at the MSL landing site located at the JPL Mars yard for the landing date/time 2012-08-06T05:17:57 using SPICE SCLK time conversion routines/tools. Version -------------------------------------------------------- 1.0.0 -- August 03, 2013 -- BVS/NAIF Initial Release. References -------------------------------------------------------- 1. SCLK Required Reading Document Implementation Details -------------------------------------------------------- LMST for MSL at the landing site JPL Mars yard and landing date/time 2012-08-06T05:17:57 can be represented by a simple linear function. The starting point for this function is the ET corresponding to the midnight LTST of the SOL 0 -- 2012-08-05 07:58:55 UTC (or 397425602.183 ET seconds past J2000). This function "runs" at the constant rate of 1.0 TDT seconds in 1 local Earth second, which is equal the SCLK rate of 86400.0 TDT seconds in 1 local Earth day that appears in the COEFFICIENTS keyword below. The ID for this clock is chosen to be 76900 to indicate that this is NOT an actual SCLK for the MSL on-board clock but a special SCLK file that enables LMST-ET time conversions using the APIs of the SCLK subsystem of SPICE. LMST Format -------------------------------------------------------- The LMST string, the conversion for which is provided by this SCLK file, consists of four fields: DDDDD:HR:MN:SC:TMSEC where: DDDDD -- count of LMST (SOL) days (0..36525) HR -- count of LMST hours (0..23) MN -- count of LMST minutes (0..59) SC -- count of LMST seconds (0..59) TMSEC -- count of LMST 10-microsecond ticks (0..99999) Usage -------------------------------------------------------- In order to use the SPICELIB SCLK family routines to convert MSL LMST at the landing site GC to ET and vice versa, this file must be loaded into the user's program by a call to the FURNSH routine CALL FURNSH( 'this_file_name' ) (FORTRAN) furnsh_c ( "this_file_name" ); (C) cspice_furnsh, 'this_file_name' (IDL) cspice_furnsh( 'this_file_name' ) (MATLAB) Once loaded, the routine SCE2S can be used to convert an ET time to an LMST string in the format DDDDD:HR:MN:SC:TMSEC: CALL SCE2S( -76900, ET, LMST ) (FORTRAN) sce2s_c ( -76900, et, maxlen, lmst ); (C) cspice_sce2s, -76900, et, lmst (IDL) lmst = cspice_sce2s( -76900, et ); (MATLAB) and the routine SCS2E can be used for backward conversion -- from LMST in DDDDD:HR:MN:SC:TMSEC format to ET: CALL SCS2E( -76900, LMST, ET ) (FORTRAN) scs2e_c ( -76900, lmst, &et ); (C) cspice_scs2e, -76900, lmst, et (IDL) et = cspice_scs2e( -76900, lmst ) (MATLAB) Inquiries -------------------------------------------------------- If you have any questions regarding this file contact NAIF at JPL Charles H. Acton, Jr (818) 354-3869 Chuck.Acton@jpl.nasa.gov Boris V. Semenov (818) 354-8136 Boris.Semenov@jpl.nasa.gov Kernel DATA -------------------------------------------------------- \begindata SCLK_KERNEL_ID = ( @2013-08-02-09:00:00 ) SCLK_DATA_TYPE_76900 = ( 1 ) SCLK01_TIME_SYSTEM_76900 = ( 2 ) SCLK01_N_FIELDS_76900 = ( 5 ) SCLK01_MODULI_76900 = ( 36525 24 60 60 100000 ) SCLK01_OFFSETS_76900 = ( 0 0 0 0 0 ) SCLK01_OUTPUT_DELIM_76900 = ( 2 ) SCLK_PARTITION_START_76900 = ( 0.00000000000000E+00 ) SCLK_PARTITION_END_76900 = ( 3.15576000000000E+14 ) SCLK01_COEFFICIENTS_76900 = ( 0.0000000000000E+00 397425602.183 86400.0 ) \begintext WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING This SCLK provides MSL LMST for the landing site at the JPL Mars yard. It must be used only for testing applications and never for flight ops tasks. WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING -- WARNING