KPL/IK HERA MILANI Laser Retroreflectors Instrument kernel ============================================================================== This instrument kernel (I-kernel) contains the Milani Laser Retroreflectors for Hera (MLRH) detector and field-of-view parameters. Version and Date ------------------------------------------------------------------------------ Version 0.1 -- Sep 21, 2023 -- Ricardo Valles, ESAC/ESA Updated Hera ID according to one provided by DSN and confirmed by FDy: from -999 to -91. Version 0.0 -- May 4, 2023 -- Alfredo Escalante Lopez, ESAC/ESA Preliminary version. References ------------------------------------------------------------------------------ 1. ``Kernel Pool Required Reading'' 2. ``C-kernel Required Reading'' 3. Hera Frames Definition Kernel (FK), latest version. 4. Milani Spacecraft Frames Kernel (FK), latest version. 5. ``Milani Laser Retroreflectors for Hera, ESA Mission to a double asteroid'', S. Agnello, Viena, Austria, PDC 2023. Contact Information ----------------------------------------------------------------------------- If you have any questions regarding this file contact the ESA SPICE Service at ESAC: Alfredo Escalante Lopez (+34) 91-8131-429 spice@sciops.esa.int or NAIF at JPL: Boris Semenov +1 (818) 354-8136 Boris.Semenov@jpl.nasa.gov Implementation Notes ------------------------------------------------------------------------------ Applications that need SPICE I-kernel data must ``load'' the I-kernel file, normally during program initialization. Loading the kernel using the SPICELIB routine FURNSH causes the data items and their associated values present in the kernel to become associated with a data structure called the ``kernel pool''. The application program may then obtain the value(s) for any IK data item using the SPICELIB routines GDPOOL, GIPOOL, GCPOOL. Routine GETFOV may be used if the file contains instrument field-of-view (FOV) specification. See [1] for details. This file was created with, and can be updated with a text editor or word processor. Conventions for Specifying Data ------------------------------------------------------------------------------ Data items are specified using ``keyword=value'' assignments [1]. All keywords referencing values in this I-kernel start with the characters `INS' followed by the NAIF MILANI instrument ID code, constructed using the spacecraft ID number (-9102) followed by the NAIF three digit ID number. The ID numbers are defined in [4] as follows: Instrument name ID -------------------- --------- MILANI_MLRH_1 -9102411 The remainder of the keyword is an underscore character followed by the unique name of the data item. For example, the boresight of MLRH_1 is specified by INS-9102411_BORESIGHT The upper bound on the length of all keywords is 32 characters. If a keyword is included in more than one file, or if the same keyword appears more than once within a single file, the last assignment supersedes any earlier assignments. Overview ------------------------------------------------------------------------------ From [5]: Milani will have onboard two picoreflectors provided by INFN, named MLRH (Milani Laser Retroreflectors for Hera). The MLRH inherit directly from the very same Martial microreflector technology for ExoMars. The two MLRH are installed on two sides of Milani to be released in Didymos orbits by the Hera mothership equipped with PALT, a LIDAR instrument (LIght Detection And Ranging). PALT will perform laser altimetry topography of the asteroids and observe the MLRHs. Thus, asteroid metric observations by Milani will be metrically tied (georeferenced) by the LIDAR to the mothership and to the asteroids topography. Since the LIDAR observation distance will be shorter that for the heritage Mars missions, the MLRH are more compact and light. They are built each with 7 reflectors of 7.16 mm diameter for a total mass of 5.1 grams, 2D size of 36 mm and 10 mm height. Mounting Alignment ------------------------------------------------------------------------------ Refer to the latest version of the Milani Spacecraft Frames Kernel (FK) [4] for the MLRH reference frame definitions and mounting alignment information. Apparent FOV Layout ------------------------------------------------------------------------------ This section provides a diagram illustrating the MLRH apparent FOV layout in the corresponding reference frame. Angular coordinate system ------------------------- +Xmlrh +Zmlrh ^ ^ 90| | _.-"|"-./ +Azim |0 .' | / `. '. |''.. .' / | / \ '. | ''.. +Za' | |/ |0 '. | '.' 180 | x----------> +Ymlrh '. | .' | | '. | .' \ / '. | .' `._ _.' '. | .' `-...-' ----------------------90 270 Optical Parameters ------------------------------------------------------------------------------ TBW. CCD Parameters ------------------------------------------------------------------------------ TBW. FOV Definitions ------------------------------------------------------------------------------ This section contains definitions for the MLRH FOVs. These definitions are provided in a format required by the SPICE (CSPICE) function GETFOV (getfov_c). The set of assignments in the data section below defines the MLRH FOVs with respect to the corresponding frames to be a half-sphere. \begindata INS-9102411_NAME = 'MILANI_MLRH_1' INS-9102411_BORESIGHT = ( 0.000, 0.000, 1.000 ) INS-9102411_FOV_FRAME = 'MILANI_MLRH_1' INS-9102411_FOV_SHAPE = 'CIRCLE' INS-9102411_FOV_CLASS_SPEC = 'ANGLES' INS-9102411_FOV_REF_VECTOR = ( 1.000, 0.000, 0.000 ) INS-9102411_FOV_REF_ANGLE = ( 90.0 ) INS-9102411_FOV_ANGLE_UNITS = 'DEGREES' INS-9102412_NAME = 'MILANI_MLRH_2' INS-9102412_BORESIGHT = ( 0.000, 0.000, 1.000 ) INS-9102412_FOV_FRAME = 'MILANI_MLRH_2' INS-9102412_FOV_SHAPE = 'CIRCLE' INS-9102412_FOV_CLASS_SPEC = 'ANGLES' INS-9102412_FOV_REF_VECTOR = ( 1.000, 0.000, 0.000 ) INS-9102412_FOV_REF_ANGLE = ( 90.0 ) INS-9102412_FOV_ANGLE_UNITS = 'DEGREES' \begintext Platform ID ------------------------------------------------------------------------------- This number is the NAIF instrument ID of the platform on which the sensors are mounted. For the Milani Laser Retroreflector for Hera (MLRH) platform is spacecraft. Please refer to the latest version of the Milani NAIF ID Codes Definitions [4] for mapping of ID codes to sensor and structure names. \begindata INS-9102411_PLATFORM_ID = ( -9102 ) INS-9102412_PLATFORM_ID = ( -9102 ) \begintext End of IK file.