KPL/IK UVS Instrument Kernel =============================================================================== This instrument kernel (I-kernel) contains the JUICE Ultraviolet Spectrograph (UVS) instrument optics, detector and field-of-view (FOV) paramters. Version and Date ------------------------------------------------------------------------------- Version 0.5 -- December 1, 2022 -- Thomas Greathouse, UVS/SwRI Updated instrument description section and SP FOV. The HP and AP FOVs are equal: Renamed -28851 to JUICE_UVS_AP_HP and removed the narrow and wide designations. Removed the JUICE_UVS_WIDE and JUICE_UVS_NARROW definitions for simplicity. Version 0.4 -- June 30, 2022 -- Marc Costa Sitja, ESAC/ESA Corrected several typos. 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 UVS instrument team. Version 0.2 -- May 11, 2016 -- Jorge Diaz del Rio, ODC Space Added instrument description section. Corrected typos in text. Modified INS-28851_FOV_FRAME keyword value (to JUICE_UVS) Version 0.1 -- February 24, 2016 -- Jorge Diaz del Rio, ODC Space Preliminary version. Pending review by the UVS 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. Davis, M. W., et al. (2020), ``Ground calibration results of the JUICE ultraviolet spectrograph'', paper presented at Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, December 01, 2020. 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 UVS sensors. This is the full list of names and IDs for the UVS sensors described by this IK file: Name NAIF ID --------------------- --------- JUICE_UVS_AP_HP -28860 JUICE_UVS_SP -28870 The remainder of the keyword name is an underscore character followed by the unique name of the data item. For example, the UVS Airglow Aperture boresight direction in the JUICE_UVS frame is specified by: INS-28851_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 ------------------------------------------------------------------------------- UVS is a long-slit ultraviolet imaging spectrograph, with a spectral bandpass including extreme and far-ultraviolet wavelengths in the 50-204 nm range, which will be used to (see [4]): 1) Explore the atmospheres, plasma interactions, and surfaces of the Galilean satellites; 2) Determine the dynamics, chemistry, and vertical structure of Jupiter's upper atmosphere, from equator to pole; and 3) Investigate the Jupiter-Io connection by quantifying energy and mass flow in the Io atmosphere, neutral clouds, and torus. UVS will obtain airglow and auroral observations, stellar and solar occultations, Jupiter transit, mutual event and surface albedo maps to address JUICE science goals even in the worst-case radiation environment near Europa. The main characteristics of UVS have been reported in [5] and are provided in the following table: ----------------------------------------------------------------------- PARAMETER VALUE --------------------------- ----------------------------------------- Wavelength Bandpass 50-204 nm Effective Area 0.8 cm2 at 121.6 nm for AP Slit FOV 0.1x7.3 degrees (AP) + 0.2 degrees (SP) Spectral Resolution (PSF) <0.6 nm FWHM, bandpass average Spectral Resolution 1.2 nm FWHM, bandpass average (filled slit) Spatial Resolution (PSF) Nyquist sampled: 0.16 degrees for AP/SP; 0.04 degrees for HP Pixel spatial platescale 0.0092+/-0.0001 degrees Pixel spectral platescale ~0.106 nm Stray Light Rejection <10-6 at 7 degreess off-boresight Detector Deadtime TD ~ 1.2 microseconds; ~ 30% loss at 360 kHz Detector Global Background Total array: 24 counts/s during radiometric Rate ground calibration Detector Output Continuous, time-tagged pixel list or programmable histogram mode with "ping-pong" memory fill. ------------------------------------------------------------------------ The telescope feeds a 15-cm Rowland circle spectrograph with a spectral bandpass of 50-204 nm. The telescope has an input aperture 4x4 cm2 and uses an off-axis parabolic (OAP) primary mirror. Light from the OAP is focused onto the spectrograph entrance slit, which has two contiguous segments with fields-of-view (FOV) of 0.1x7.3 degrees and 0.2x0.2 degrees projected onto the sky (the 0.2x0.2 degrees box is used to accommodate the 0.11 degrees diameter Sun during solar occultations). Light entering the slit is dispersed by a toroidal diffraction grating that focuses the UV bandpass onto a curved microchannel plate (MCP) cross delay line (XDL) detector with a solar blind, UV-sensitive CsI photocathode. Tantalum/Tungsten (TaW) plates contiguously surround the detector and electronics assemblies, shielding the detector and sensitive parts from general particle radiation and high-energy electrons in particular. The detector electronics are located behind the detector. In a chamber beside the spectrograph are located the high-voltage power supply (HVPS), low-voltage power supply (LVPS), command and data handling (C&DH) electronics, heater/actuator activation electronics, and event processing electronics. The detector electronics receive event pulses from the detector and provide a digital indication of the spatial and spectral location of each event to the C&DH. Event processing electronics receive valid individual events and process them into: 1) pixel list (a time ordered record of detected events) or 2) programmable histogram. A main entrance "airglow port" (AP) is used for most observations (e.g., airglow, aurora, surface mapping, and stellar occultations). Two aperture doors exist on UVS. The first completely blocks light from entering the main entrance aperture allowing for full protection of the UVS instrument optical train and for the ability to take dark observations. The second aperture door, called the "high-spatial_resolution port" (HP) has a 1x1 cm2 hole in its center. It effectively stops down the instrument allowing for high spatial resolution observation of bright sources at the cost of 1/16 the throughput. Both the AP and HP have the same FOV on the sky. A separate "solar port" (SP), at an angle of 60 degrees to the AP and stopped down to a 0.25 mm diameter hole, allows for observations of solar occultations. Time-tagging (pixel-list mode) and programmable spectral imaging (histogram mode) allow for observational flexibility and optimal data management. Mounting Alignment ------------------------------------------------------------------------------- Refer to the latest version of the JUICE Frames Definition Kernel (FK) [3] for the UVS reference frame definitions and mounting alignment information. UVS AP and HP Slit Layout ------------------------------------------------------------------------------- This section provides a diagram illustrating the UVS apparent slit layout in the JUICE_UVS reference frame, not to scale. ^ +Xuvs (along slit) | | | | v .--|--. ---------------------- | | ^ ----> | | <---- 0.2 degrees | | | | '-.|.-' --------- | ||| ^ ^ | ||| | | | ||| 0.2 deg. | | | ||| | | ||| | | ||| | | ||| | | ||| | | ---->|||<---- 0.1 degrees | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | +Yuvs (cross slit) ||| | | <-----------------------|o| JUICE_UVS_AP_HP (boresight) | 7.5deg. | ||| | | ||| | | ||| | | ||| | | ||| 7.3 deg. | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| | | ||| v v '-' ---------------------- UVS +Z axis (instrument main boresight) out of the page Optical Distortion ------------------------------------------------------------------------------- TBD; need consultation with UVS instrument team Optical Parameters ------------------------------------------------------------------------------- TBD; need consultation with UVS instrument team Detector Parameters -------------------------------------------------------- TBD; need consultation with UVS instrument team UVS Airglow Port Field of View Definition ------------------------------------------------------------------------------- The UVS Airglow Port field of view is defined based on the shape of the spectrograph entrance slit, which has two contiguous segments with fields of view of 0.1x7.3 degrees and 0.2x0.2 degrees (see [4], p.54). The following FOV definition corresponds to the NAIF Body Name: JUICE_UVS_AP_HP. \begindata INS-28860_FOV_FRAME = 'JUICE_UVS' INS-28860_FOV_SHAPE = 'POLYGON' INS-28860_BORESIGHT = ( 0.000, 0.000, 1.000 ) INS-28860_FOV_CLASS_SPEC = 'CORNERS' INS-28860_FOV_BOUNDARY_CORNERS = ( -0.0654031044274081 0.0008708943631663 0.997858544821993 -0.0654031044274081 -0.0008708943631663 0.997858544821993 0.0619195296276383 -0.0008708943631663 0.998080764965291 0.0619194588007405 -0.0017453257076200 0.998079623306677 0.0654030296158094 -0.0017453257076200 0.997857403417567 0.0654030296158094 0.0017453257076200 0.997857403417567 0.0619194588007405 0.0017453257076200 0.998079623306677 0.0619195296276383 0.0008708943631663 0.998080764965291 ) \begintext UVS Solar port Slit Layout ------------------------------------------------------------------------------- This section provides a diagram illustrating the Solar Port FOV in the JUICE_UVS_SP reference frame, not to scale. ^ +Xuvs_sp (along slit) | | | | | | v .--|--. ---------------------- | | ^ | o | JUICE_UVS_SP (boresight) | 0.2 degrees ----> | | <---- | '-.|.-' --------- | ||| ^ ^ | ||| | | | ||| 0.2 deg. | | | ||| | | ||| | | ---->|||<---- 0.1 degrees | | ||| | | +Yuvs_sp (cross slit) ||| | | <-----------------------||| | 1.2 deg. | ||| | | ||| | | ||| 1.0 deg. | | ||| | | ||| v v '-' ---------------------- UVS_SP +Z axis (Solar port boresight) out of the page UVS Solar Port Field of View Definition ------------------------------------------------------------------------------- The UVS Sun Port field of view is defined and boresighted through the center of the 0.2x0.2 degrees box at the end of the slit (see [4], p.53). Given the size of the pickoff mirror used for the solar port, only a fraction of the full slit is observed ~1 degree along the slit away from the box (see image above). This will be updated after the solar port is commissioned in flight. Please note that the FOV reference and cross angles are defined with half angle values. The following FOV definition corresponds to the NAIF Body Name: JUICE_UVS_SP. \begindata INS-28870_FOV_FRAME = 'JUICE_UVS_SP' INS-28870_FOV_SHAPE = 'POLYGON' INS-28870_BORESIGHT = ( 0.000000 0.000000 1.000000 ) INS-28870_FOV_CLASS_SPEC = 'CORNERS' INS-28851_FOV_BOUNDARY_CORNERS = ( -0.0191974435001612 0.0008726645610295 0.9998154044151306 -0.0191974435001612 -0.0008726645610295 0.9998154044151306 -0.0017453284235671 -0.0008726645610295 0.9999980926513672 -0.0017453284235671 -0.0017453284235671 0.9999969601631165 0.0017453284235671 -0.0017453284235671 0.9999969601631165 0.0017453284235671 0.0017453284235671 0.9999969601631165 -0.0017453284235671 0.0017453284235671 0.9999969601631165 -0.0017453284235671 0.0008726645610295 0.9999980926513672 ) \begintext End of IK file.