KPL/IK MAJIS Instrument Kernel =============================================================================== This instrument kernel (I-kernel) contains the JUICE Moons And Jupiter Imaging Spectrometer (MAJIS) instrument optics, detector and field-of-view (FOV) parameters. Version and Date ------------------------------------------------------------------------------- Version 0.8 -- June 29, 2023 -- Alfredo Escalante Lopez, ESAC/ESA Decreased 90 degrees half-angles to 89.99994 degrees limit. Version 0.7 -- December 3, 2022 -- Marc Costa Sitja, ESAC/ESA Francois Poulet, UniParis Claire Vallat, ESAC/ESA Benoit Seignovert, OSUNA/CNRS Removed JUICE_MAJIS_FULL and added JUICE_MAJIS_ENVELOPE. Removed along-track detector parameters given that they correspond to the spectral dimension and updated VISNIR and IR detector centers. Version 0.6 -- October 21, 2022 -- Marc Costa Sitja, ESAC/ESA Added MAJIS radiator -- JUICE_MAJIS_RAD -- FOV definition. Version 0.5 -- July 30, 2019 -- Marc Costa Sitja, ESAC/ESA Updated instrument description, FOV definitions and added Optical and Detector parameters in accordance with the updated EIDB version ([5]). Version 0.4 -- July 11, 2016 -- Marc Costa Sitja, ESAC/ESA Added reference to the NAIF Body ID for all the FOV definitions. Corrected JUICE_MAJIS_IR_B4 FOV frame, all FOV reference angles -were specified as full cone instead of half cone- and several typos. Initial Release. Pending review by the MAJIS instrument team. Version 0.3 -- June 04, 2016 -- Marc Costa Sitja, ESAC/ESA Updated all NAIF ID codes from -907* to -28* since the JUICE spacecraft NAIF ID has been updated from -907 to -28. Initial Release. Pending review by the MAJIS instrument team. Version 0.2 -- May 11, 2016 -- Jorge Diaz del Rio, ODC Space Corrected typos in text. Preliminary version. Pending review by the MAJIS instrument team. Version 0.1 -- March 02, 2016 -- Jorge Diaz del Rio, ODC Space Preliminary version. Pending review by the MAJIS instrument and JUICE Science Operations Working Group team. Version 0.0 -- July 24, 2013 -- Marc Costa Sitja, ISDEFE/ESA Initial Release. References ------------------------------------------------------------------------------- 1. ``Kernel Pool Required Reading'' 2. ``C-kernel Required Reading'' 3. JUICE Frames Definition Kernel (FK), latest version. 4. ``JUICE - Jupiter Icy Moons Explorer. Exploring the emergence of habitable worlds around gas giants. Definition Study report,'' ESA/SRE(2014)1, September 2014 (JUICE Red book v1.0) 5. ``JUICE - JUpiter Icy Moons Explorer MAJIS - Moons And Jupiter Imaging Spectrometer Experiment Interface Document - Part B,'' JUI-IAS-MAJ-EID-001 Issue 3.2, 15 March 2019 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 or the JUICE Science Operations Center at ESAC: Marc Costa Sitja (+34) 646-746-711 Marc.Costa@ext.esa.int Implementation Notes ------------------------------------------------------------------------------- Applications that need SPICE I-kernel data must ``load'' the I-kernel file, normally during program initialization. The SPICE routine FURNSH loads a kernel file into the pool as shown below. CALL FURNSH ( 'frame_kernel_name' ) -- FORTRAN furnsh_c ( "frame_kernel_name" ); -- C cspice_furnsh, frame_kernel_name -- IDL cspice_furnsh( 'frame_kernel_name' ) -- MATLAB 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''. Once the file has been loaded, the SPICE routine GETFOV (getfov_c in C, cspice_getfov in IDL and MATLAB) can be used to retrieve FOV parameters for a given instrument or structure. The application program may obtain the value(s) for any other IK data item using the SPICELIB routines GDPOOL, GIPOOL, GCPOOL (gdpool_c, gipool_c, gcpool_c in C, cspice_gdpool, cspice_gipool, cspice_gcpool in IDL and MATLAB). See [1] for details. This file was created with, and can be updated with a text editor or word processor. Naming Conventions and Conventions for Specifying Data ------------------------------------------------------------------------------- All names referencing values in this IK file start with the characters `INS' followed by the NAIF JUICE spacecraft ID number (-28) followed by a NAIF three digit ID code for one of the MAJIS ``sensors''. This is the full list of names and IDs for the MAJIS sensors described by this IK file: Name NAIF ID --------------------- --------- JUICE_MAJIS -28400 JUICE_MAJIS_VISNIR -28410 JUICE_MAJIS_VISNIR_B2 -28412 JUICE_MAJIS_VISNIR_B4 -28414 JUICE_MAJIS_IR -28420 JUICE_MAJIS_IR_B2 -28422 JUICE_MAJIS_IR_B4 -28424 The remainder of the keyword name is an underscore character followed by the unique name of the data item. For example, the MAJIS Infrared sensor boresight direction in the JUICE_MAJIS_IR frame is specified by: INS-28420_BORESIGHT The upper bound on the length of the name of any data item is 32 characters. If the same item is included in more than one file, or if the same item appears more than once within a single file, the latest value supersedes any earlier values. Instrument Description and Overview ------------------------------------------------------------------------------- This section is extracted from the Experiment Interface Document - Part B (see [5]) Instrument Description: ----------------------- MAJIS consists of double channel imaging spectrometer operating in the VIS-NIR range (0.5–2.35 microns) and the IR range (2.25–5.54 microns). The dual channel spectrometer architecture shares a single slit fed by a three-mirror anastigmatic telescope equipped with a pointing/scanning mirror. The FOV covered by a MAJIS frame is 3.4 degrees x 150 micro radians (centered on the boresight). Thanks to the scanning mechanism MAJIS has a pointing/scanning/compensation capability in the across slit direction up to +/-4 degrees with respect to boresight. A dichroic window placed after the entrance slit separates the VISNIR and IR beam channels towards each one of the spectrometer’s grating. Both channels operate simultaneously, the bridging region of the two channels being set at ~2.3 microns. Two 1024x1024 pixels (18x18 microns pixel pitch) HgCdTe H1RG detectors are used at the focal planes of the two channels. Each detector contains 4 lines or columns constituted of reference pixels on each of the 4 sides. It therefore provides a useful area of 508 x 508 pixels with a pitch of 36x36 microns after binning 2x2. In order to minimize the impact on the optical design in comparison to the proposal, the selected approach was to keep the same f- number while adjusting the slit width, leading to 400 binned pixels across the FOV. At the typical altitude of 500 km (GCO-500), it will provide a coverage over a 30 km wide region with a 75 m/pix at maximum spatial resolution. The spatial resolution can be adapted by binning depending on the observational conditions. The spectral sampling of the VISNIR and IR channels are 3.65 nm/band and 6.45 nm/band respectively over 508 spectral elements. The two focal planes will be equipped with blocking linear variable optical filters. As typical for an imaging spectrometer, the instantaneous acquisition of the 2D detectors consists of the slit image sampled over the 400 binned pixels in the spatial direction and diffracted in the spectral direction by the grating across the 508 bands. Since the two channels operate simultaneously, the instrument is able to collect an entire 0.5-5.54 mictons spectral range for each pixel of the slit image. A 3D data cube (hyperspectral data cube) can be then be built over time by repeating consecutive IFOV step acquisitions. A shutter mechanism enables dark current and thermal background frame acquisitions preceding, during and after the scientific frame sequence. MAJIS has the flexibility to operate either in pushbroom mode or in scanning mode, depending on the different phases of the mission. In pushbroom mode, once the scanning mirror is fixed at a pre-defined pointing position, repeated acquisitions are performed while the S/C moves along the scene. The scanning mode is implemented so as to build a cube when the S/C dwell time is too high (motion compensation) or too low (scan mode) with respect to the integration time. As an example, the scanning mechanism can compensate the S/C motion for high spatial resolution observations at low distance from the target like during GCO500 or Europa’s flybys by increasing the dwell time. The scanning mode can also be used to acquire hyper spectral cubes and mosaics of Jupiter and Galilean satellites during transfer, elliptical or high altitude circular orbits. Optical design -------------- The optical design can be divided in two main parts: the telescope (focal length of 240 mm with three mirrors anastigmatic solution) and the two grating spectrometers (VIS-NIR and IR), interfaced by the entrance slit, which can be thought as an element of both optical subsystems. The dichroic filter is designed so that it reflects all the radiation with wavelength longer than 2.25 microns towards the VIS-NIR channel and transmits all the radiation with wavelength shorter than 2.35 microns towards the IR channel. The collimator has a focal length of 105 mm and it is a Schmidt-off axis with a specular correcting plate for each spectrometer channel. This collimator layout guarantees a very good correction for the spherical aberration and the coma for both channels. Scan mirror unit ---------------- The scan mirror unit has the following functionalities: a) it allows to build up a 2-D image with similar spatial resolution on both directions (along and across slit, the latter being the scan direction) when the relative speed of the target and MAJIS is too low (large slant distance); b) it allows to visually increase the dwell time through a motion compensation mode when the relative speed is too high (short slant distance); c) it allows to reach the position of the ICUs to perform in-flight radiometric calibrations. The mechanical rotation of the mirror is obtained by two cantilevered flexural pivots driven by a DC motor coupled to a phase shift resolver. The unit ensures the following functional requirements: a) operative mechanical scan angle: +/-2 degrees (equivalent to an optical angle of +/- 4 degrees); b) calibration mechanical scan angle: +8.5 degrees. Binning ------- In order to maximize the scientific return of the instrument and to minimize the resource usage, several scientific operative modes are implemented. This approach guarantees flexibility of operation as well as full support to the science operations goals. The on board software for the two VIS-NIR and IR channels shall be capable of re-sampling the full frame instantaneous acquisition of 400 spatial x 508 spectral pixels in bins of variable size (x2, x4) in the spatial and spectral domain. In this way the spatial and spectral resolutions shall vary while maintaining the nominal 3.4 degree FOV, according to the modes described hereafter: Spatial Spectral Frame size Mode Binning iFOV(*) Binning nm/band(**) Samples Bands(***) ---- ------- ------- ------- ----------- ------- ----- Nominal 1x1 1 150urad 1 03.66/06.51 400 508 2x1 2 300urad 1 03.66/06.51 200 508 4x1 4 600urad 1 03.66/06.51 100 508 1x2 1 150urad 2 07.32/13.02 400 254 2x2 2 300urad 2 07.32/13.02 200 254 4x2 4 600urad 2 07.32/13.02 100 254 1x4 1 150urad 4 14.64/26.04 400 127 2x4 2 300urad 4 14.64/26.04 200 127 4x4 4 600urad 4 14.64/26.04 100 127 Calibration Full Frame N/A Full Frame <3.66/<6.51 1016 1016 1x1 1 N/A 264 <3.66/<6.51 400 508 (*) Spatial resolution resulting from adding the iFoV the number of binned pixels. The units are micro-radians (urad). (**) Spectral resolution for the VIS-NIR/IR sensors. (***) The spectral binning modes given here are just examples. There is indeed a high flexibility in the spectral binning and spectral editing that could lead to spectral bands up to 640. Scientific Performance ---------------------- Parameter Unit Note Value ------------------- ---------- --------------------------- ------------ Spectral Range microns 0.5-54 Spectral sampling nm VIS-NIR @ 0.5-2.35 microns 3.66 IR @ 2.25-5.54 microns 6.51 Pixel Resolution km GEO(*) 0.075-1.5 (**) GCO500 0.075 Europa/Callisto/Ganymede 10-3 Europa/Callisto CA <1 Jupiter 75-125-226 Minor Targets (Io,rings,..) 50+(Io) - 120+(rings) VNIR IR - - - - - - Signal to Noise ratio GEO/GCO500/Callisto >100 >30 (SNR) (***) Europa >100 >10 Jupiter Hot Spots >100 Jupiter Auroras >10 Io averaged >100 (*) In the GEO phase Ganymede as well as during close flybys, spatial binning by 2 or 4 can be implemented. (**) The spatial resolution range is given for some targets. Please take into account that they are rough values. (***) SNR significantly depends on wavelength Mounting Alignment ------------------------------------------------------------------------------- Refer to the latest version of the JUICE Frames Definition Kernel (FK) [3] for the MAJIS reference frame definitions and mounting alignment information. MAJIS Apparent Field-of-View Layouts ------------------------------------------------------------------------------- This diagram illustrates the MAJIS VIS-NIR and IR apparent FOV layout for "zero" scan mirror position in the corresponding reference frame when operating in normal mode (no-binning). These FOVs are associated with detector instrument IDs (-28410 and -28420). ^ +Yvisnir (along track) | +Yir ^ direction | | | of | 150urad | | flight | | v Pixel 1 | Pixel 400 --- +---------|---------+ | 1 line | o-------------> +Xvisnir (across track) --- +-------------------+ +Xir ^ 400 pixels/line | | 3.4 degrees | |<----------------->| | | Boresight (+Z axis) is out of the page This diagram illustrates the MAJIS VIS-NIR and IR apparent FOV layout for "zero" scan mirror position in the corresponding reference frame when operating in 2xN binning (2 pixels spatial binning mode). These FOVs are associated with detector instrument IDs (-28412 and -28422). ^ +Yvisnir_b2 (along track) | +Yir_b2 ^ direction | | | of | 300urad | | flight | | v Pixel 1 | Pixel 200 --- +---------|---------+ | 1 line | o-------------> +Xvisnir_b2 (across track) --- +-------------------+ +Xir_b2 ^ 200 pixels/line | | 3.4 degrees | |<----------------->| | | Boresight (+Z axis) is out of the page This diagram illustrates the MAJIS VIS-NIR and IR apparent FOV layout for "zero" scan mirror position in the corresponding reference frame when operating in 4xN binning (4 pixels spatial binning mode). These FOVs are associated with detector instrument IDs (-28414 and -28424). ^ +Yvisnir_b4 (along track) | +Yir_b4 ^ direction | | | of | 600urad | | flight | | v Pixel 1 | Pixel 100 --- +---------|---------+ | 1 line | o-------------> +Xvisnir_b4 (across track) --- +-------------------+ +Xir_b4 ^ 100 pixels/line | | 3.4 degrees | |<----------------->| | | Boresight (+Z axis) is out of the page Optical Parameters ------------------------------------------------------------------------------- The following MAJIS VIS-NIR and IR nominal first order optical parameters are included in the data section below, from [5]: ---------------------------------------------------------- parameter 1xN 2xN 4xN ---------------------------------------------------------- Focal Length, mm 240 240 240 f/ratio f/3.2 f/3.2 f/3.2 IFOV, rad/pixel Cross-track 0.000148 0.000297 0.000593 Along-track 0.000150 0.000300 0.000600 Field of view (deg) Cross-track 3.4 3.4 3.4 Along-track 0.008594 0.017188 0.034377 ---------------------------------------------------------- The keywords below provide nominal values from the table above. Angular size values in the keywords are given radians, with the cross-track size being the first value and the along-track size being the second value in each pair. \begindata INS-28410_FOCAL_LENGTH = ( 240.0 ) INS-28410_F/RATIO = ( 3.2 ) INS-28410_FOV_ANGULAR_SIZE = ( 3.4, 0.008594 ) INS-28410_IFOV = ( 0.000148, 0.000150 ) INS-28420_FOCAL_LENGTH = ( 240.0 ) INS-28420_F/RATIO = ( 3.2 ) INS-28420_FOV_ANGULAR_SIZE = ( 3.4, 0.008594 ) INS-28420_IFOV = ( 0.000148, 0.000150 ) INS-28412_FOCAL_LENGTH = ( 240.0 ) INS-28412_F/RATIO = ( 3.2 ) INS-28412_FOV_ANGULAR_SIZE = ( 3.4, 0.017188 ) INS-28412_IFOV = ( 0.000297, 0.000300 ) INS-28422_FOCAL_LENGTH = ( 240.0 ) INS-28422_F/RATIO = ( 3.2 ) INS-28422_FOV_ANGULAR_SIZE = ( 3.4, 0.017188 ) INS-28422_IFOV = ( 0.000297, 0.000300 ) INS-28414_FOCAL_LENGTH = ( 240.0 ) INS-28414_F/RATIO = ( 3.2 ) INS-28414_FOV_ANGULAR_SIZE = ( 3.4, 0.034377 ) INS-28414_IFOV = ( 0.000593, 0.000600 ) INS-28424_FOCAL_LENGTH = ( 240.0 ) INS-28424_F/RATIO = ( 3.2 ) INS-28424_FOV_ANGULAR_SIZE = ( 3.4, 0.034377 ) INS-28424_IFOV = ( 0.000593, 0.000600 ) \begintext Detector Parameters -------------------------------------------------------- The nominal MAJIS detector parameters from [5] are: ------------------------------------------------------------ parameter 1xN 2xN 4xN ------------------------------------------------------------ Detector Array Size/Physical (1) Spectral direction 1016 1016 1016 Spatial direction 800 800 800 Detector Array Size/Spatial Along-track N/A N/A N/A Cross-track 800 800 800 Detector Array Center/Spatial (3) Along-track N/A N/A N/A Across-track VIS-NIR 499 499 499 Across-track IR 491 491 491 Pixel Size, microns/Spatial Along-track N/A N/A N/A Across-track 36 72 144 ------------------------------------------------------------ (1) CCD pixels are then binned at detector level, PE (Proximity Electronics) level and CU (Compression Unit) level and assuming IR reads out the same number of pixels as VIS-NIR. Original detectors are 1024x1024 pixels (18x18 um pixel pitch). (2) size of a 2x2 binned pixel (3) Windowing with flexible selection of the center can be implemented The values are given in microns for PIXEL_SIZE keywords and in counts for PIXEL_SAMPLES, PIXEL_LINES, and CENTER keywords. \begindata INS-28410_PIXEL_SIZE = ( 36, 36 ) INS-28410_PIXEL_SAMPLES = ( 800 ) INS-28410_CCD_CENTER = ( 499 ) INS-28420_PIXEL_SIZE = ( 36, 36 ) INS-28420_PIXEL_SAMPLES = ( 800 ) INS-28420_CCD_CENTER = ( 491 ) INS-28412_PIXEL_SIZE = ( 72, 72 ) INS-28412_PIXEL_SAMPLES = ( 800 ) INS-28412_CCD_CENTER = ( 499 ) INS-28422_PIXEL_SIZE = ( 72, 72 ) INS-28422_PIXEL_SAMPLES = ( 800 ) INS-28422_CCD_CENTER = ( 491 ) INS-28414_PIXEL_SIZE = ( 144, 144 ) INS-28414_PIXEL_SAMPLES = ( 800 ) INS-28414_CCD_CENTER = ( 499 ) INS-28424_PIXEL_SIZE = ( 144, 144 ) INS-28424_PIXEL_SAMPLES = ( 800 ) INS-28424_CCD_CENTER = ( 491 ) \begintext MAJIS Field of View Definitions ------------------------------------------------------------------------------- The set of assignments in the data section below defines the MAJIS VIS-NIR and IR non-scanning FOVs with respect to the corresponding frames to be rectangles with the corners defined by the first and last pixels of the spatial, cross-track line and the boresight along the +Z axis. These FOV definitions use angular extent style specification with the cross and along track angular sizes taken from the ``Optics Parameters'' section above. Please note that the FOV reference and cross angles are defined with half angle values. Visible and Near-Infrared single line, no-binning FoV ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Corresponds to the NAIF Body Name: JUICE_MAJIS_VISNIR. \begindata INS-28410_NAME = 'JUICE_MAJIS_VISNIR' INS-28410_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28410_FOV_FRAME = 'JUICE_MAJIS_VISNIR' INS-28410_FOV_SHAPE = 'RECTANGLE' INS-28410_FOV_CLASS_SPEC = 'ANGLES' INS-28410_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28410_FOV_REF_ANGLE = ( 0.0000750 ) INS-28410_FOV_CROSS_ANGLE = ( 0.029670597283903602 ) INS-28410_FOV_ANGLE_UNITS = 'RADIANS' \begintext Visible and Near-Infrared single line, 2-pixel spatial binning FoV ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Corresponds to the NAIF Body Name: JUICE_MAJIS_VISNIR_B2. \begindata INS-28412_NAME = 'JUICE_MAJIS_VISNIR_B2' INS-28412_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28412_FOV_FRAME = 'JUICE_MAJIS_VISNIR' INS-28412_FOV_SHAPE = 'RECTANGLE' INS-28412_FOV_CLASS_SPEC = 'ANGLES' INS-28412_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28412_FOV_REF_ANGLE = ( 0.0001500 ) INS-28412_FOV_CROSS_ANGLE = ( 0.029670597283903602 ) INS-28412_FOV_ANGLE_UNITS = 'RADIANS' \begintext Visible and Near-Infrared single line, 4-pixel spatial binning FoV ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Corresponds to the NAIF Body Name: JUICE_MAJIS_VISNIR_B4. \begindata INS-28414_NAME = 'JUICE_MAJIS_VISNIR_B4' INS-28414_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28414_FOV_FRAME = 'JUICE_MAJIS_VISNIR' INS-28414_FOV_SHAPE = 'RECTANGLE' INS-28414_FOV_CLASS_SPEC = 'ANGLES' INS-28414_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28414_FOV_REF_ANGLE = ( 0.0003000 ) INS-28414_FOV_CROSS_ANGLE = ( 0.029670597283903602 ) INS-28414_FOV_ANGLE_UNITS = 'RADIANS' \begintext Infrared single line, no-binning FoV ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Corresponds to the NAIF Body Name: JUICE_MAJIS_IR. \begindata INS-28420_NAME = 'JUICE_MAJIS_IR' INS-28420_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28420_FOV_FRAME = 'JUICE_MAJIS_IR' INS-28420_FOV_SHAPE = 'RECTANGLE' INS-28420_FOV_CLASS_SPEC = 'ANGLES' INS-28420_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28420_FOV_REF_ANGLE = ( 0.0000750 ) INS-28420_FOV_CROSS_ANGLE = ( 0.029670597283903602 ) INS-28420_FOV_ANGLE_UNITS = 'RADIANS' \begintext Infrared single line, 2-pixel spatial binning FoV ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Corresponds to the NAIF Body Name: JUICE_MAJIS_IR_B2. \begindata INS-28422_NAME = 'JUICE_MAJIS_IR_B2' INS-28422_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28422_FOV_FRAME = 'JUICE_MAJIS_IR' INS-28422_FOV_SHAPE = 'RECTANGLE' INS-28422_FOV_CLASS_SPEC = 'ANGLES' INS-28422_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28422_FOV_REF_ANGLE = ( 0.000150 ) INS-28422_FOV_CROSS_ANGLE = ( 0.029670597283903602 ) INS-28422_FOV_ANGLE_UNITS = 'RADIANS' \begintext Infrared single line, 4-pixel spatial binning FoV ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Corresponds to the NAIF Body Name: JUICE_MAJIS_IR_B4. \begindata INS-28424_NAME = 'JUICE_MAJIS_IR_B4' INS-28424_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28424_FOV_FRAME = 'JUICE_MAJIS_IR' INS-28424_FOV_SHAPE = 'RECTANGLE' INS-28424_FOV_CLASS_SPEC = 'ANGLES' INS-28424_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28424_FOV_REF_ANGLE = ( 0.0003000 ) INS-28424_FOV_CROSS_ANGLE = ( 0.029670597283903602 ) INS-28424_FOV_ANGLE_UNITS = 'RADIANS' \begintext MAJIS Radiator FoV ~~~~~~~~~~~~~~~~~~ The MAJIS cryogenic and standard radiators FoV are modelled for planning purposes. Corresponds to the NAIF Body Name: JUICE_MAJIS_RAD. The set of assignments in the data section below defines the MAJIS Radiator FOV. This FOV is meant to be used to understand if the radiator is illuminated. The half-angle values have been set to the maximum FOV angular radius limit of 89.99994 degrees. \begindata INS-28430_NAME = 'JUICE_MAJIS_RAD' INS-28430_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28430_FOV_FRAME = 'JUICE_MAJIS_RAD' INS-28430_FOV_SHAPE = 'CIRCLE' INS-28430_FOV_CLASS_SPEC = 'ANGLES' INS-28430_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28430_FOV_REF_ANGLE = ( 89.99994 ) INS-28430_FOV_ANGLE_UNITS = 'DEGREES' \begintext MAJIS Envelope FoV ~~~~~~~~~~~~~~~~~~ This diagram illustrates the MAJIS VIS-NIR and IR FoV ``envelope'' layout for coverage analysis purposes. This FOV is associated with instrument ID -28440 and is useful only for rough coverage analysis as in reality the instrument does not articulate the mirror over the whole possible range. ^ +Ymajis (along track) | | | ^ direction --- *---------|---------+ | of ^ | | | | flight | 3.4 | | | | degrees | | | | | o-------------> +Xmajis (across track) | | | | | | V | | --- +-------------------+ | | 3.4 degrees | |<----------------->| | | Boresight (+Z axis) is out of the page Corresponds to the NAIF Body Name: JUICE_MAJIS_ENVELOPE. The set of assignments in the data section below defines the MAJIS FoV resulting from a theoretical full, +/- 2.0 degrees scan mirror sweep about the +X axis with respect to MAJIS_BASE frame to be a rectangle with the corners defined by the first and last pixels of the spatial, along-track line in the first and last scan positions and the boresight along the +Z axis. Although this should result in a 8.0x3.4 degrees FoV the full mirror sweep is also used to compensate the S/C motion to build a sequence of 400 lines and geometrically this limits the spatial extent of the FOV to 3.4x3.4 degrees. Please note that the FOV reference and cross angles are defined with half angle values. \begindata INS-28440_NAME = 'JUICE_MAJIS_ENVELOPE' INS-28440_BORESIGHT = ( 0.000 0.000 1.000 ) INS-28440_FOV_FRAME = 'JUICE_MAJIS_BASE' INS-28440_FOV_SHAPE = 'RECTANGLE' INS-28440_FOV_CLASS_SPEC = 'ANGLES' INS-28440_FOV_REF_VECTOR = ( 0.000 1.000 0.000 ) INS-28440_FOV_REF_ANGLE = ( 1.70000 ) INS-28440_FOV_CROSS_ANGLE = ( 1.70000 ) INS-28440_FOV_ANGLE_UNITS = 'DEGREES' \begintext The Detector and Optical parameters that would correspond to the JUICE_MAJIS_ENVELOPE are provided for convenience hereunder. \begindata INS-28440_FOCAL_LENGTH = ( 240.0 ) INS-28440_F/RATIO = ( 3.2 ) INS-28440_FOV_ANGULAR_SIZE = ( 3.4, 3.4 ) INS-28440_IFOV = ( 0.000093, 0.000150 ) INS-28440_PIXEL_SIZE = ( 36, 36 ) INS-28440_PIXEL_SAMPLES = ( 400 ) INS-28440_PIXEL_LINES = ( 400 ) \begintext End of IK file.