KPL/SCLK APM1 SCLK File --- Nominal Clock =========================================================================== This file is a SPICE spacecraft clock (SCLK) kernel containing information required for converting APM1 spacecraft on-board clock times to other time systems (UTC, ET, etc.) and vice versa. This SCLK kernel represents the nominal APM1 on-board clock, which was synchronized with UTC seconds past J2000 TDB. Version and Date -------------------------------------------------------- Version 1 -- August 20, 2024 -- Derek Maggard, CLPS Initial release. Contact Information -------------------------------------------------------- If you have any questions regarding this file contact: Derek R. Maggard, CLPS, Derek.R.Maggard@nasa.gov References -------------------------------------------------------- 1. SCLK Required Reading Document 2. MAKCLK User's Guide Document 3. SFOC SCLKvSCET SIS Document 4. ``M-PE1-CQ-0101J'' Payload Interface Control Document (ICD) - LETS Production/History of this SCLK file -------------------------------------------------------- This file was generated by the NAIF utility program MAKCLK with a fake SCLKvSCET file (see the comment sections ``SCLKvSCET File Contents'' and ``MAKCLK Setup File'' below for the MAKCLK setup file). The clock was calibrated from the ground periodically during flight and is estimated to have drifted less than ~20ms between calibrations. The inherent error in UTC time even after calibration is +/- ~72ms. The term ``fake sclk_scet'' is used because neither ``DUT'' nor the ``SFDU keyword lines'' were prepared (they are not read by MAKCLK). Note that this clock's zero epoch is 0.0 ET while its correlation represents a nominal clock (rate = 1.0) counting UTC seconds. [4] Usage -------------------------------------------------------- This file and an appropriate leap seconds kernel (LSK) must be loaded into the user's program by a call to the FURNSH subroutine: CALL FURNSH ( 'file_name' ) -- FORTRAN furnsh_c ( "file_name" ); -- C cspice_furnsh, 'file_name' -- IDL cspice_furnsh( 'file_name' ) -- MATLAB in order to use the SPICELIB SCLK family of subroutines to convert spacecraft on-board clock to ET and vice versa. SCLK Format -------------------------------------------------------- The on-board clock, the conversion for which is provided by this SCLK file, consists of two fields: SSSSSSSSSS:FFFFF where: SSSSSSSSSS -- count of on-board seconds FFFFF -- count of fractions of a second with one fraction being 1/65536 of a second Fake SCLKvSCET File Contents -------------------------------------------------------- CCSD3ZS00001$$sclk$$NJPL3KS0L015$$scet$$ CCSD3RE00000$$scet$$NJPL3IS00613$$data$$ *____SCLK0_______ ____SCET0____________ _DUT__ _SCLKRATE___ 000000000.000 2000-001T11:58:55.816 0 1.000000000 189345664.000 2005-365T23:59:59.816 0 2.000000000 189345665.000 2006-001T00:00:00.816 0 1.000000000 284040064.000 2008-366T23:59:59.816 0 2.000000000 284040065.000 2009-001T00:00:00.816 0 1.000000000 394372864.000 2012-182T23:59:59.816 0 2.000000000 394372865.000 2012-183T00:00:00.816 0 1.000000000 488980864.000 2015-181T23:59:59.816 0 2.000000000 488980865.000 2015-182T00:00:00.816 0 1.000000000 536500864.000 2016-366T23:59:59.816 0 2.000000000 536500865.000 2017-001T00:00:00.816 0 1.000000000 CCSD3RE00000$$data$$CCSD3RE00000$$sclk$$ MAKCLK Setup file -------------------------------------------------------- SCLKSCET_FILE = apm1.sclkscet OLD_SCLK_KERNEL = apm1_template.tsc FILE_NAME = apm1.tsc NAIF_SPACECRAFT_ID = -244 LEAPSECONDS_FILE = /media/sf_Shared/kernels/lsk/naif0012.tls PARTITION_TOLERANCE = 394 LOG_FILE = apm1.log Kernel DATA -------------------------------------------------------- This file is a SPICE spacecraft clock (SCLK) kernel. This file was generated by the NAIF MOSPICE utility program MAKCLK, version 5.1.0, 26-OCT-2021. Please refer to the SCLK Required Reading file, NAIF document number 222, and the MAKCLK User's Guide, NAIF document number 267, for information regarding this kernel file. \begindata SCLK_KERNEL_ID = ( @2024-08-20/12:21:21.30 ) SCLK_DATA_TYPE_244 = ( 1 ) SCLK01_TIME_SYSTEM_244 = ( 2 ) SCLK01_N_FIELDS_244 = ( 2 ) SCLK01_MODULI_244 = ( 4294967296 65536 ) SCLK01_OFFSETS_244 = ( 0 0 ) SCLK01_OUTPUT_DELIM_244 = ( 1 ) SCLK_PARTITION_START_244 = ( 0.0000000000000E+00 ) SCLK_PARTITION_END_244 = ( 2.8147497671065E+14 ) SCLK01_COEFFICIENTS_244 = ( 0.0000000000000E+00 -3.5763036976277E-10 1.0000000000000E+00 1.2408957435904E+13 1.8934566400000E+08 2.0000000000000E+00 1.2408957501440E+13 1.8934566600000E+08 1.0000000000000E+00 1.8614849634304E+13 2.8404006500000E+08 2.0000000000000E+00 1.8614849699840E+13 2.8404006700000E+08 1.0000000000000E+00 2.5845620015104E+13 3.9437286600000E+08 2.0000000000000E+00 2.5845620080640E+13 3.9437286800000E+08 1.0000000000000E+00 3.2045849903104E+13 4.8898086700000E+08 2.0000000000000E+00 3.2045849968640E+13 4.8898086900000E+08 1.0000000000000E+00 3.5160120623104E+13 5.3650086800000E+08 2.0000000000000E+00 3.5160120688640E+13 5.3650087000000E+08 1.0000000000000E+00 ) \begintext