KPL/FK Gaia Spacecraft Frames Kernel ============================================================================= This frame kernel contains complete set of frame definitions for Gaia including definitions for the Gaia fixed and Gaia science instrument frames. This kernel also contains NAIF ID/name mapping for the Gaia science instruments and s/c structures (see the last section of the file). Version and Date ----------------------------------------------------------------------------- Version 0.1 -- May 9, 2023 -- Ricardo Valles Blanco, ESAC/ESA Corrected typos and updated contact information. Version 0.0 -- October 23, 2019 -- Marc Costa Sitja, ESAC/ESA Preliminary Version. Only basic ID and frame definitions. References ----------------------------------------------------------------------------- 1. ``Frames Required Reading'' 2. ``Kernel Pool Required Reading'' 3. ``C-Kernel Required Reading'' Contact Information ----------------------------------------------------------------------------- If you have any questions regarding this file contact the ESA SPICE Service (ESS) at ESAC: Alfredo Escalante Lopez (+34) 91-8131-429 spice@sciops.esa.int Implementation Notes ----------------------------------------------------------------------------- This file is used by the SPICE system as follows: programs that make use of this frame kernel must "load" the kernel normally during program initialization. Loading the kernel associates the data items with their names in a data structure called the "kernel pool". The SPICELIB routine FURNSH loads a kernel into the pool as shown below: FORTRAN: (SPICELIB) CALL FURNSH ( frame_kernel_name ) C: (CSPICE) furnsh_c ( frame_kernel_name ); IDL: (ICY) cspice_furnsh, frame_kernel_name MATLAB: (MICE) cspice_furnsh ( 'frame_kernel_name' ) PYTHON: (SPICEYPY)* furnsh( frame_kernel_name ) 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. * SPICEPY is a non-official, community developed Python wrapper for the NAIF SPICE toolkit. Its development is managed on Github. It is available at: https://github.com/AndrewAnnex/SpiceyPy Gaia Mission NAIF ID Codes ----------------------------------------------------------------------------- The following names and NAIF ID codes are assigned to the Gaia spacecraft, its structures and science instruments (the keywords implementing these definitions are located in the section "Gaia Mission NAIF ID Codes -- Definition Section" at the end of this file): Gaia Spacecraft and Spacecraft Structures names/IDs: GAIA -123 GAIA_SPACECRAFT -123000 (synonym: GAIA_SC) Gaia Mission Frames ----------------------------------------------------------------------------- The following Gaia frames are defined in this kernel file: Name Relative to Type NAIF ID ====================== ======================== ========== ========= Spacecraft frames: ------------------ GAIA_SPACECRAFT J2000 CK -123000 SPICE 'Built-in' PCK frames in use by Gaia (3): ------------------------------------------------------ IAU_EARTH J2000 PCK built-in (3) Data for these frames is loaded using either the PCK file "pckVVVVV.tpc" (VVVVV is the version number) Gaia Frames Hierarchy ----------------------------------------------------------------------------- The diagram below shows the Gaia spacecraft and its structures frame hierarchy (not including science instrument frames.) "J2000" INERTIAL +------------------------------------+ | | |<-pck | | | V | "EARTH_FIXED" | ------------- | | |<-ck | V "GAIA_SPACECRAFT" ----------------- . . . . V Individual instrument frame trees are provided in the corresponding sections of this file Gaia Spacecraft and Spacecraft Structures Frames ======================================================================== This section of the file contains the definitions of the spacecraft and spacecraft structures frames. Gaia Spacecraft Frame -------------------------------------- The Gaia spacecraft frame is defined as follows: - +Z axis is along the nominal boresight direction of the science deck; - +X axis is along the nominal boresight direction of the HGA; - +Y axis completes the right-hand frame; - the origin of this frame is the launch vehicle interface point. Since the orientation of the GAIA_SPACECRAFT frame is computed on-board, sent down in telemetry, and stored in the s/c CK files, it is defined as a CK-based frame. \begindata FRAME_GAIA_SPACECRAFT = -123000 FRAME_-123000_NAME = 'GAIA_SPACECRAFT' FRAME_-123000_CLASS = 3 FRAME_-123000_CLASS_ID = -123000 FRAME_-123000_CENTER = -123 CK_-123000_SCLK = -123 CK_-123000_SPK = -123 \begintext Gaia NAIF ID Codes to Name Mapping ------------------------------------------------------------------------------ This section contains name to NAIF ID mappings for the Gaia mission. Once the contents of this file is loaded into the KERNEL POOL, these mappings become available within SPICE, making it possible to use names instead of ID code in the high level SPICE routine calls. Spacecraft: ---------------------------------------------------------------- This table presents the Gaia Spacecraft and its main structures' names. --------------------- ------- -------------------------- Name ID Synonyms --------------------- ------- -------------------------- GAIA -123 GAIA_SPACECRAFT -123000 GAIA_SC --------------------- ------- -------------------------- Notes: -- 'GAIA_SC' and 'GAIA_SPACECRAFT' are synonyms and all map to the Gaia S/C bus structure ID (-123000); \begindata NAIF_BODY_NAME += ( 'GAIA' ) NAIF_BODY_CODE += ( -123 ) NAIF_BODY_NAME += ( 'GAIA_SC' ) NAIF_BODY_CODE += ( -123000 ) NAIF_BODY_NAME += ( 'GAIA_SPACECRAFT' ) NAIF_BODY_CODE += ( -123000 ) \begintext End of FK file.