This SPK file is a Cassini trajectory reconstruction encompassing a portion of the Saturn orbital mission. It is one part of a set of SPK files which together form a comprehensive reconstruction of the Cassini tour and the orbits of Saturn and its satellites. It is provided by Duane Roth of the Cassini Navigation Team and Robert Jacobson of the Solar System Dynamics Group at JPL. A preliminary description of the work is described in Paper No. EPSC-DPS2019-338 entitled "The Comprehensive Reconstruction of the Cassini Tour, the Orbits of Saturn and its Satellites, and the Gravity Field of the Saturnian System", authored by Robert Jacobson, Duane Roth, Julie Bellerose, and William Folkner and presented at the EPSC-DPS Joint Meeting 2019. A final description will be presented at the 2020 AAS/AIAA Astrodynamics Specialist Conference (August 2020). This reconstruction and others from this collection form the definitive set for the Cassini tour of Saturn and its satellites and are intended to supersede earlier dated versions. In contrast to previously released reconstructions, these were generated using the same planet and satellite ephemerides, rotational poles, and gravity models throughout. Satellite ephemeris SAT427 is the satellite ephemeris associated with the reconstruction and bundled in the SPK. The Saturn planetary ephemeris used and bundled in the reconstruction employed a local correction to JPL planetary ephemeris DE437. The trajectory file naming convention begins with YYMMDD which specifies the delivery date. RU is appended to the delivery date to specify that the file is a reconstruction and that uniform models were used for Saturnian system natural bodies. An underscore followed by SCPSE designates the file as 'bundled' (contains spacecraft, planet, and satellite ephemeris information). The next two fields, also separated by underscores, are the file start and end times in YYDOY format. Finally, bsp is added as a suffix. For example, 200128RU_SCPSE_17235_17258.bsp refers to a spice kernel delivered on January 28, 2020 that is bundled and begins on Day of Year 235 in 2017 and ends on DOY 258 in 2017. Altogether, a set of uniform spice kernels with the same delivery date span the entire Saturn orbital missions (Prime, Equinox, and Solstice) with no gaps or overlaps in coverage. The log from the SPKMERGE run that created this SPK and internal comments from the source spacecraft trajectory, planetary ephemeris, and satellite ephemeris SPKs are provided below. ; 200128RU_SCPSE_14187_14223.bsp LOG FILE ; Created 2020-02-12/13:45:59.00. ; ; BEGIN SPKMERGE COMMANDS LEAPSECONDS_KERNEL = /kernels/gen/lsk/naif0012.tls SPK_KERNEL = 200128RU_SCPSE_14187_14223.bsp SOURCE_SPK_KERNEL = pfile.T104.bsp INCLUDE_COMMENTS = YES BODIES = -82 BEGIN_TIME = 2014 JUL 06 11:58:52.816 END_TIME = 2014 AUG 11 17:58:53.817 SOURCE_SPK_KERNEL = plneph.sat427.bsp INCLUDE_COMMENTS = YES BODIES = 499, 299, 199, 399, 301, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 BEGIN_TIME = 2014 JUL 06 11:58:52.816 END_TIME = 2014 AUG 11 17:58:53.817 SOURCE_SPK_KERNEL = sat427l.bsp INCLUDE_COMMENTS = YES BODIES = 699, 632, 634, 614, 613, 612, 609, 608, 607, 606, 605, 604, 603, 602, 601 BEGIN_TIME = 2014 JUL 06 11:58:52.816 END_TIME = 2014 AUG 11 17:58:53.817 ; END SPKMERGE COMMANDS ; pfile.bsp LOG FILE ; ; Created 2020-01-04/09:27:02.09. ; ; BEGIN NIOSPK COMMANDS SPK_FILE = pfile.bsp SOURCE_NIO_FILE = pfile.nio BEGIN_TIME = CAL-ET 2014 JUL 06 12:00:00.000 END_TIME = CAL-ET 2014 AUG 11 18:00:01.000 ; END NIOSPK COMMANDS ; /home/sat/Ephemerides/Planetary/saturn.bsp LOG FILE ; ; Created 2019-11-07/10:04:27.00. ; ; BEGIN NIOSPK COMMANDS SPK_FILE = /home/sat/Ephemerides/Planetary/saturn.bsp INCLUDE_TEXT_FILE = /home/sat/Ephemerides/Planetary/Notes/sat427.txt SOURCE_NIO_FILE = /home/sat/Ephemerides/Planetary/saturn.nio BEGIN_TIME = CAL-ET 1849 DEC 26 00:00:00.000 END_TIME = CAL-ET 2074 DEC 22 00:00:00.000 ; END NIOSPK COMMANDS Update to DE437 from the SAT427 comprehensive fit. Ephcor inputs are: PARAMS = 'DMW6','DP6','DQ6','EDW6','DA6','DE6','GM6', EPOCH(1) = 2396752.5, $ 12/26/1849, $ de422 partials EPOCH(2) = 2478944.5, $ 01/07/2075, $ de422 partials $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$ corrections to DE437 $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $ Astrometric, Pioneer, Voyager, and Cassini data: SAT427.10 DELTAS(01)= -9.855660532932377E-11, DELTAS(02)= 1.113605122862356E-09, DELTAS(03)= 5.332257816552498E-10, DELTAS(04)= -6.388047766719665E-12, DELTAS(05)= -7.695925569243433E-12, DELTAS(06)= -2.318917937612761E-12, DELTAS(07)= -2.061910405755048E-01, ; /home/sat/Ephemerides/Saturn/sat427l.bsp LOG FILE ; ; Created 2020-01-23/14:33:16.87. ; ; BEGIN NIOSPK COMMANDS SPK_FILE = /home/sat/Ephemerides/Saturn/sat427l.bsp INCLUDE_TEXT_FILE = /home/sat/Ephemerides/Delivery/Saturn/sat427l.txt SOURCE_NIO_FILE = /home/sat/Ephemerides/Saturn/sat427l.nio BEGIN_TIME = CAL-ET 1849 DEC 28 00:00:00.000 END_TIME = CAL-ET 2150 JAN 08 00:00:00.000 ; END NIOSPK COMMANDS Satellite Ephemeris File Release Satellite Ephemeris: SAT427.23 Location: ssd.jpl.nasa.gov/pub/eph/satellites/nio/LINUX_PC/sat427l.nio Enter SATEPHMERGE/18 07-Jan-2020 17:47:26.526 linked 02-Oct-2017 12:47:09 Merge of back and forward Astrometric, Pioneer, Voyager, and Cassini data: SAT427.23 Ephemeris Version Number: 20 Timespan from JED 2396754.500(28-DEC-1849) to JED 2506338.500(08-JAN-2150) File Epoch Julian Date: 2456928.50 Master Interval: 18.0000 Days Equinox Reference Julian Date: 2451545.00 Planetary Ephemeris Number: DE-0438/LE-0438 Bodies on the File: Name Number GM NDIV NDEG Model Mimas 601 2.503617062809250E+00 24 15 SATORBINT Enceladus 602 7.210497553340731E+00 24 12 SATORBINT Tethys 603 4.121405263872402E+01 12 14 SATORBINT Dione 604 7.311617801921636E+01 12 11 SATORBINT Rhea 605 1.539409077211430E+02 8 11 SATORBINT Titan 606 8.978137369591670E+03 6 12 SATORBINT Hyperion 607 3.704182596063880E-01 6 10 SATORBINT Iapetus 608 1.205081845217891E+02 2 10 SATORBINT Phoebe 609 5.581081743011904E-01 1 8 SATORBINT Helene 612 4.551624250415933E-04 12 11 SATORBINT Telesto 613 0.000000000000000E+00 12 15 SATORBINT Calypso 614 0.000000000000000E+00 12 15 SATORBINT Polydeuces 634 0.000000000000000E+00 12 11 SATORBINT Methone 632 0.000000000000000E+00 24 15 SATORBINT Saturn 699 3.793120615901047E+07 12 12 SATORBINT System 3.794058484179918E+07 Additional Constants on the File: AU 1.495978707000000E+08 RADIUS 6.033000000000000E+04 J602 1.629054544344128E-02 J603 1.150196016868669E-07 J604 -9.351416449565978E-04 J605 -6.082226919241670E-08 J606 8.669267417716214E-05 J607 4.988317096231317E-07 J608 -1.408041010654190E-05 POLTIM 2.451545000000000E+06 ZACPL6 4.059470176352203E+01 ZDEPL6 8.353441774005661E+01 DACPL6 -5.300647274880106E-02 DDEPL6 -6.093128003179784E-03 WPL6 3.882680785270414E+01 WDP6 8.181387763690900E+02 RINGM1 3.900000000000000E-02 RINGM2 7.840000000000000E-01 RINGM4 3.000000000000000E-01 GM7 5.794556465751792E+06 GM8 6.836527100580024E+06 GM5 1.267127641334462E+08 GM10 1.327132332639221E+11 J609 9.315923512031980E-07 J610 5.246512931947152E-06 J611 1.929625145508324E-07 J612 -6.660669035902763E-07 J613 4.400341170870734E-08 J614 1.087569659422105E-07 J615 5.724837044519656E-08 J616 4.052305521868366E-07 J617 2.154409479353933E-09 J618 -2.598194298948179E-07 J619 -1.585414895654257E-08 J620 -1.975252738253841E-07 RA_AMPL1 3.131427128000000E-02 RA_FAZE1 3.360106550207000E+02 RA_FREQ1 5.123786306323000E+01 RA_AMPL2 -2.475697210000000E-04 RA_FAZE2 2.799702555848000E+02 RA_FREQ2 7.226641819047000E+03 RA_AMPL3 3.653243150000000E-04 RA_FAZE3 8.125668960084001E+00 RA_FREQ3 1.008121600826000E+03 DE_AMPL1 3.519572074000000E-03 DE_FAZE1 3.360106550207000E+02 DE_FREQ1 5.123786306323000E+01 DE_AMPL2 -2.778981300000000E-05 DE_FAZE2 2.799702555848000E+02 DE_FREQ2 7.226641819047000E+03 DE_AMPL3 3.921320100000000E-05 DE_FAZE3 8.125668960084001E+00 DE_FREQ3 1.008121600826000E+03 W_AMPL1 -3.111510242900000E-02 W_FAZE1 3.360106550207000E+02 W_FREQ1 5.123786306323000E+01 W_AMPL2 2.459950970000000E-04 W_FAZE2 2.799702555848000E+02 W_FREQ2 7.226641819047000E+03 W_AMPL3 -3.630007350000000E-04 W_FAZE3 8.125668960084001E+00 W_FREQ3 1.008121600826000E+03 C_ring_RI 7.450000000000000E+04 C_ring_RO 9.200000000000000E+04 B_ring_RI 9.200000000000000E+04 B_ring_RO 1.175000000000000E+05 A_ring_RI 1.223570000000000E+05 A_ring_RO 1.367800000000000E+05 600K2 4.058927330362964E-01 601LAG 1.000000000000000E-10 602LAG 1.000000000000000E-10 603LAG 1.000000000000000E-10 604LAG 1.000000000000000E-10 605LAG 1.000000000000000E-10 606LAG 1.000000000000000E-10 RELSCL 1.000000000000000E+00 Chebyshev interpolation error: 7.500 meters Release to: Horizons/NAIF Time: 23-Jan-2020 12:36: 6 Preparer: R. A. Jacobson Comments: Ephemerides for the final comprehensive Cassini reconstruction