KPL/FK Didymos System Frames Kernel ======================================================================== This frame kernel contains a complete set of frame definitions for the Didymos system including NAIF ID/name mapping for the the asteroid system and, the name to ID mappings for the DART target body DSK surfaces. Version and Date ------------------------------------------------------------------------ Version 007 -- October 6, 2023 -- Hari Nair, JHU/APL Update DIMORPHOS_FIXED switch frame parameters, using Dimorphos orbit solution 542. Adjust impact time to 2022-09-26T23:14:24.184. Version 006 -- September 11, 2023 -- Hari Nair, JHU/APL Revised description of Dimorphos post-impact frame. Add complete list of defined frames in the "Asteroid Frames" section. Update DSK surface name/id mapping. Version 005 -- June 13, 2023 -- Hari Nair, JHU/APL Update DIMORPHOS_FIXED switch frame parameters, using Dimorphos orbit solution 527. Define post-impact frame as a dynamic frame, with X axis pointing to Didymos center and Z axis parallel to Didymos pole. Version 004 -- May 26, 2023 -- Hari Nair, JHU/APL Update DIMORPHOS_FIXED switch frame parameters, using Dimorphos orbit solution 523. Version 003 -- February 1, 2023 -- Hari Nair, JHU/APL Implement DIMORPHOS_FIXED as a switch frame, using Dimorphos orbit solution 516. Version 002 -- January 12, 2023 -- Hari Nair, JHU/APL Add Name/Code bindings for DSK surfaces. Version 001 -- July 25, 2022 - Hari Nair, JHU/APL Fixed typo: DIMORPHOS_FIXED relative to IAU_DIMORPHOS Version 000 -- September 1, 2021 - Marc Costa Sitja, NAIF/JPL First version. References ------------------------------------------------------------------------ 1. ``Frames Required Reading'' 2. ``Kernel Pool Required Reading'' 3. ``DS-Kernel Required Reading'' Contact Information ------------------------------------------------------------------------ Hari Nair, JHU/APL, Hari.Nair@jhuapl.edu Olivier Barnouin, JHU/APL, Olivier.Barnouin@jhuapl.edu Alyssa Bailey, NAIF/JPL, alyssa.m.bailey@jpl.nasa.gov Implementation Notes ------------------------------------------------------------------------ This file is used by the SPICE system as follows: programs that make use of this kernel must ``load'' the kernel, normally during program initialization. The SPICE routine FURNSH loads a kernel file into the pool as shown below. CALL FURNSH ( 'kernel_name; ) -- FORTRAN furnsh_c ( "kernel_name" ); -- C cspice_furnsh, kernel_name -- IDL cspice_furnsh( 'kernel_name' ) -- MATLAB In order for a program or routine to extract data from the pool, the SPICELIB routines GDPOOL, GIPOOL, and GCPOOL are used. See [2] for more details. This file was created and may be updated with a text editor or word processor. Asteroid NAIF ID Codes -- Summary Section ------------------------------------------------------------------------ The following names and NAIF ID codes are assigned to the Didymos system (the keywords implementing these definitions are located in the section "Didymos System NAIF ID Codes -- Definition Section" later in this file): Asteroid Binary System names/IDs*: DIDYMOS BARYCENTER 20065803 65803 DIDYMOS 920065803 DIDYMOS 920065803 (65803) DIDYMOS I (DIMORPHOS) 120065803 DIMORPHOS 120065803 (*) The Minor Planet Designation (MPC) for the Didymos system is 65803. The NAIF ID of the system barycenter is 20065803. The NAIF ID of the primary (Didymos) is 920065803. The NAIF ID of the secondary (Dimorphos) is 120065803. Asteroid Frames ------------------------------------------------------------------------ The following Didymos system frames are defined in this kernel file: Name Relative to Type NAIF ID ====================== =================== ============ ========= IAU_DIDYMOS J2000 PCK 10113 DIDYMOS_FIXED IAU_DIDYMOS FIXED 920065803 IAU_DIMORPHOS J2000 PCK 10114 DIMORPHOS_FIXED_PRE J2000 DYNAMIC 1200658031 DIMORPHOS_FIXED_POST J2000 DYNAMIC 1200658032 DIMORPHOS_FIXED DIMORPHOS_FIXED_PRE SWITCH 120065803 DIMORPHOS_FIXED DIMORPHOS_FIXED_POST SWITCH 120065803 Asteroid Body Fixed Frames ------------------------------------------------------------------------ This section of the file contains the body-fixed frame definition for one of the DART mission targets: asteroid Didymos and Dimorphos. Didymos frames -------------------------------------- The asteroid Didymos body-fixed frame -- IAU_DIDYMOS -- is defined as follows: - +Z axis is the asteroid rotation axis pointed towards the positive pole - +X axis points towards the prime meridian - +Y axis completes the right handed frame - the origin of the frame is at the asteroid center of mass. Since the asteroid rotation data is expected to be provided in a text PCK in the form compliant with the IAU rotation model, the IAU_DIDYMOS frame is defined as a PCK based frame. This definition is included in all SPICE Toolkits version N0067 or later. \begindata FRAME_IAU_DIDYMOS = 10113 FRAME_10113_NAME = 'IAU_DIDYMOS' FRAME_10113_CLASS = 2 FRAME_10113_CLASS_ID = 920065803 FRAME_10113_CENTER = 920065803 OBJECT_920065803_FRAME = 'IAU_DIDYMOS' \begintext In addition, the DIDYMOS_FIXED frame is defined as a reference frame alias of IAU_DIDYMOS. \begindata FRAME_DIDYMOS_FIXED = 920065803 FRAME_920065803_NAME = 'DIDYMOS_FIXED' FRAME_920065803_CLASS = 4 FRAME_920065803_CLASS_ID = 920065803 FRAME_920065803_CENTER = 920065803 TKFRAME_920065803_RELATIVE = 'IAU_DIDYMOS' TKFRAME_920065803_SPEC = 'MATRIX' TKFRAME_920065803_MATRIX = ( 1 0 0 0 1 0 0 0 1 ) \begintext Dimorphos frames -------------------------------------- The asteroid satellite Dimorphos body-fixed frame -- IAU_DIMORPHOS -- is defined as follows: - +Z axis is the asteroid satellite rotation axis pointed towards the positive pole - +X axis points towards the prime meridian - +Y axis completes the right handed frame - the origin of the frame is at the asteroid satellite center of mass. Since the asteroid rotation data is expected to be provided in a text PCK in the form compliant with the IAU rotation model, the IAU_DIMORPHOS frame is defined as a PCK based frame. This definition is included in all SPICE Toolkits version N0067 or superior. \begindata FRAME_IAU_DIMORPHOS = 10114 FRAME_10114_NAME = 'IAU_DIMORPHOS' FRAME_10114_CLASS = 2 FRAME_10114_CLASS_ID = 120065803 FRAME_10114_CENTER = 120065803 OBJECT_120065803_FRAME = 'IAU_DIMORPHOS' \begintext Most users will likely want to use DIMORPHOS_FIXED rather than IAU_DIMORPHOS since DIMORPHOS_FIXED correctly represents the changed rotation of Dimorphos before and after the DART impact. The DIMORPHOS_FIXED frame is defined as a switch frame aligned with the Euler dynamic frame DIMORPHOS_FIXED_PRE before the impact (2022 SEP 26 23:14:24.184 UTC or 2022 SEP 26 23:15:33.366361 TDB) and with the dynamic frame DIMORPHOS_FIXED_POST after the impact. DIMORPHOS_FIXED_PRE implements the pre-impact Dimorphos rotation model specified in the PCK didymos_system_15.tpc. These rotation parameters correspond to Dimorphos orbit solution 542. DIMORPHOS_FIXED_POST is a dynamic frame where the X axis points from Dimorphos center to Didymos center. The Z axis is parallel to the IAU_DIDYMOS Z axis. The start and stop time of the DIMORPHOS_FIXED frame availability are arbitrarily set to the start and stop times of the extra-long DE441 SPKs. \begindata FRAME_DIMORPHOS_FIXED = 120065803 FRAME_120065803_NAME = 'DIMORPHOS_FIXED' FRAME_120065803_CLASS = 6 FRAME_120065803_CLASS_ID = 120065803 FRAME_120065803_CENTER = 120065803 FRAME_120065803_ALIGNED_WITH = ( 'DIMORPHOS_FIXED_PRE' 'DIMORPHOS_FIXED_POST' ) FRAME_120065803_START = ( @13201B.C.-MAY-06-00:00:00.000 @2022-09-26-23:15:33.366361 ) FRAME_120065803_STOP = ( @2022-09-26-23:15:33.366361 @17191-MAR-15-00:00:00.000 ) \begintext The following fragments from didymos_system_15.tpc provide Dimorphos rotation keywords before impact: Pre-impact: BODY120065803_POLE_RA = ( 69.326861266078069, 0, 0) BODY120065803_POLE_DEC = ( -72.724550395829496, 0, 0) BODY120065803_PM = ( 73.070565080143595, 724.724388306834840, 1.0270736140e-06) These models are referenced to the J2000 frame and the J2000 epoch. The DIMORPHOS_FIXED_PRE frame is defined as an Euler dynamic frame with its coefficients derived from the pre-impact PCK keyword values as described in the "Example of an Euler Frame" section of the Frames Required Reading document: POLE_RA 69.326861266078069 -> ANGLE_1 -159.326861266078069 POLE_DEC -72.724550395829496 -> ANGLE_2 -162.724550395829496 PM[1] 73.070565080143595 -> ANGLE_3[1] -73.070565080143595 PM[2] 724.724388306834840 -> ANGLE_3[2] -0.8388013753551329E-02 PM[3] 1.0270736140e-06 -> ANGLE_3[3] -0.13758595009216392E-15 The DIMORPHOS_FIXED_POST frame is defined as a dynamic frame where the X axis points from Dimorphos center to Didymos center. The Z axis is parallel to the IAU_DIMORPHOS Z axis. The DIMORPHOS_FIXED_PRE frame ID 1200658031 and DIMORPHOS_FIXED_POST frame ID 1200658032 are chosen arbitrarily by appending one more digit to the DIMORPHOS_FIXED frame ID. \begindata FRAME_DIMORPHOS_FIXED_PRE = 1200658031 FRAME_1200658031_NAME = 'DIMORPHOS_FIXED_PRE' FRAME_1200658031_CLASS = 5 FRAME_1200658031_CLASS_ID = 1200658031 FRAME_1200658031_CENTER = 120065803 FRAME_1200658031_RELATIVE = 'J2000' FRAME_1200658031_DEF_STYLE = 'PARAMETERIZED' FRAME_1200658031_FAMILY = 'EULER' FRAME_1200658031_EPOCH = @2000-JAN-1/12:00:00 FRAME_1200658031_AXES = ( 3 1 3 ) FRAME_1200658031_UNITS = 'DEGREES' FRAME_1200658031_ANGLE_1_COEFFS = ( -159.326861266078069 ) FRAME_1200658031_ANGLE_2_COEFFS = ( -162.724550395829496 ) FRAME_1200658031_ANGLE_3_COEFFS = ( -73.070565080143595 -0.8388013753551329E-02 -0.13758595009216392E-15 ) FRAME_DIMORPHOS_FIXED_POST = 1200658032 FRAME_1200658032_NAME = 'DIMORPHOS_FIXED_POST' FRAME_1200658032_CLASS = 5 FRAME_1200658032_CLASS_ID = 1200658032 FRAME_1200658032_CENTER = 120065803 FRAME_1200658032_RELATIVE = 'J2000' FRAME_1200658032_DEF_STYLE = 'PARAMETERIZED' FRAME_1200658032_FAMILY = 'TWO-VECTOR' FRAME_1200658032_PRI_AXIS = 'X' FRAME_1200658032_PRI_VECTOR_DEF = 'OBSERVER_TARGET_POSITION' FRAME_1200658032_PRI_OBSERVER = 'DIMORPHOS' FRAME_1200658032_PRI_TARGET = 'DIDYMOS' FRAME_1200658032_PRI_ABCORR = 'NONE' FRAME_1200658032_SEC_AXIS = 'Z' FRAME_1200658032_SEC_VECTOR_DEF = 'CONSTANT' FRAME_1200658032_SEC_SPEC = 'RECTANGULAR' FRAME_1200658032_SEC_FRAME = 'IAU_DIDYMOS' FRAME_1200658032_SEC_VECTOR = ( 0 0 1 ) \begintext Didymos System NAIF ID Codes -- Definitions ======================================================================== This section contains name to NAIF ID mappings for the Didymos system. Once the contents of this file are loaded into the KERNEL POOL, these mappings become available within SPICE, making it possible to use names instead of ID code in high level SPICE routine calls. These mappings are included in all version N0067 or superior SPICE Toolkits. \begindata NAIF_BODY_NAME += ( 'DIDYMOS BARYCENTER' ) NAIF_BODY_CODE += ( 20065803 ) NAIF_BODY_NAME += ( '65803 DIDYMOS' ) NAIF_BODY_CODE += ( 920065803 ) NAIF_BODY_NAME += ( 'DIDYMOS' ) NAIF_BODY_CODE += ( 920065803 ) NAIF_BODY_NAME += ( '(65803) DIDYMOS I (DIMORPHOS)' ) NAIF_BODY_CODE += ( 120065803 ) NAIF_BODY_NAME += ( 'DIMORPHOS' ) NAIF_BODY_CODE += ( 120065803 ) \begintext Didymos System DSK Surface ID Codes -- Definitions ======================================================================== This section contains name to ID mappings for the DART target body DSK surfaces. These mappings are supported by all SPICE toolkits with integrated DSK capabilities (version N0066 or later). Asteroid Didymos Surface name/IDs: DSK Surface Name ID Body ID ========================== ========= ========= DIDYMOS_50680MM_RDR_V001 250680001 920065803 DART_DIDYMOS_01165MM_SPC_V003 201165003 920065803 DART_DIDYMOS_02329MM_SPC_V003 202329003 920065803 DART_DIDYMOS_04657MM_SPC_V003 204657003 920065803 DART_DIDYMOS_09309MM_SPC_V003 209309003 920065803 Name-ID Mapping keywords: \begindata NAIF_SURFACE_NAME += 'DIDYMOS_50680MM_RDR_V001' NAIF_SURFACE_CODE += 250680001 NAIF_SURFACE_BODY += 920065803 NAIF_SURFACE_NAME += 'DART_DIDYMOS_01165MM_SPC_V003' NAIF_SURFACE_CODE += 201165003 NAIF_SURFACE_BODY += 920065803 NAIF_SURFACE_NAME += 'DART_DIDYMOS_02329MM_SPC_V003' NAIF_SURFACE_CODE += 202329003 NAIF_SURFACE_BODY += 920065803 NAIF_SURFACE_NAME += 'DART_DIDYMOS_04657MM_SPC_V003' NAIF_SURFACE_CODE += 204657003 NAIF_SURFACE_BODY += 920065803 NAIF_SURFACE_NAME += 'DART_DIDYMOS_09309MM_SPC_V003' NAIF_SURFACE_CODE += 209309003 NAIF_SURFACE_BODY += 920065803 \begintext Satellite asteroid Dimorphos Surface name/IDs: DSK Surface Name ID Body ID ============================== ========= ========= DART_DIMORPHOS_00250MM_SPC_V003 200250003 120065803 DART_DIMORPHOS_00490MM_SPC_V003 200490003 120065803 DART_DIMORPHOS_00980MM_SPC_V003 200980003 120065803 DART_DIMORPHOS_01960MM_SPC_V003 201960003 120065803 DART_DIMORPHOS_00243MM_SPC_V004 200243004 120065803 DART_DIMORPHOS_00487MM_SPC_V004 200487004 120065803 DART_DIMORPHOS_00972MM_SPC_V004 200972004 120065803 DART_DIMORPHOS_01940MM_SPC_V004 201940004 120065803 Name-ID Mapping keywords: \begindata NAIF_SURFACE_NAME += 'DART_DIMORPHOS_00250MM_SPC_V003' NAIF_SURFACE_CODE += 200250003 NAIF_SURFACE_BODY += 120065803 NAIF_SURFACE_NAME += 'DART_DIMORPHOS_00490MM_SPC_V003' NAIF_SURFACE_CODE += 200490003 NAIF_SURFACE_BODY += 120065803 NAIF_SURFACE_NAME += 'DART_DIMORPHOS_00980MM_SPC_V003' NAIF_SURFACE_CODE += 200980003 NAIF_SURFACE_BODY += 120065803 NAIF_SURFACE_NAME += 'DART_DIMORPHOS_01960MM_SPC_V003' NAIF_SURFACE_CODE += 201960003 NAIF_SURFACE_BODY += 120065803 NAIF_SURFACE_NAME += 'DART_DIMORPHOS_00243MM_SPC_V004' NAIF_SURFACE_CODE += 200243004 NAIF_SURFACE_BODY += 120065803 NAIF_SURFACE_NAME += 'DART_DIMORPHOS_00487MM_SPC_V004' NAIF_SURFACE_CODE += 200487004 NAIF_SURFACE_BODY += 120065803 NAIF_SURFACE_NAME += 'DART_DIMORPHOS_00972MM_SPC_V004' NAIF_SURFACE_CODE += 200972004 NAIF_SURFACE_BODY += 120065803 NAIF_SURFACE_NAME += 'DART_DIMORPHOS_01940MM_SPC_V004' NAIF_SURFACE_CODE += 201940004 NAIF_SURFACE_BODY += 120065803 \begintext End of FK.