KPL/IK OSIRIS Instrument kernel =========================================================================== This instrument kernel (I-kernel) contains Rosetta Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) Narrow Angle Camera (NAC) and Wide Angle Camera (WAC) optics, detector, and field-of-view parameters. Version and Date --------------------------------------------------------------------------- Version 1.4 -- May 22, 2017 -- Marc Costa Sitja, ESAC/ESA Cecilia Tubiana, MPS Boris Semenov, NAIF/JPL Replaced the OSIRIS user manual from 2002 with Keller et al. 2007. and added latest version of the SIS. Corrected the Overview section by adding a note about optical parameters varying pixel by pixel in non-geometric distortion corrected images and removing the optical parameters from the Summary table. Added an additional sensor definition for NAC and WAC to account for geometric distortion correction. Updated Optical Parameters and Field-of-View definitions accordingly. Updated descriptions to better describe the apparent FOV layout. Version 1.3 -- March 6, 2016 -- Marc Costa Sitja, ESAC/ESA Corrected wrong focal length for NAC. Version 1.2 -- March 24, 2014 -- B. Geiger, ESAC/ESA Corrected wrong IFOV for WAC. Version 1.1 -- June 21, 2011 -- J. Vazquez, ESAC/ESA M. Kueppers, ESAC/ESA IFOV for WAC and NAC updated. Version 1.0 -- March 15, 2005 -- Boris Semenov, NAIF/JPL Version number change for the first official release. Version 0.2 -- March 15, 2005 -- Boris Semenov, NAIF/JPL Corrected typo in WAC FOV boresight definition. Version 0.1 -- September 2, 2004 -- Boris Semenov, NAIF/JPL Filled in instrument overview section (copied from [6]). Version 0.0 -- August 3, 2004 -- Boris Semenov, NAIF/JPL Initial release. References --------------------------------------------------------------------------- 1. ``Kernel Pool Required Reading'' 2. ``C-kernel Required Reading'' 3. ``OSIRIS EID, Part B'', ROS-EST-RS-3016/EID B, 2001-05-15 4. Rosetta Frames Definition Kernel (FK), latest version. 5. ``OSIRIS - THE SCIENTIFIC CAMERA SYSTEM ONBOARD ROSETTA'', Keller et al., Space Science Reviews (2007) 128: 433-506, 2007. 6. ``OSIRIS Experiment Data Record and Software Interface Specification'', Issue 1, Max Planck Institute for Solar System Research. 7. ``OSIRIS Instrument Kernel review'', E-mail from Cecilia Tubiana, MPS, 4 April 2017. 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 Rosetta instrument ID code, constructed using the spacecraft ID number (-226) followed by the NAIF three digit ID number for non-geometric distortion corrected OSIRIS NAC (111) and WAC (112) and geometric distortion corrected OSIRIS NAC (113) and WAC (114). These IDs are defined in [4] as follows: Instrument name ID -------------------- ------- ROS_OSIRIS_NAC -226111 ROS_OSIRIS_WAC -226112 ROS_OSIRIS_NAC_DIST -226113 ROS_OSIRIS_WAC_DIST -226114 The remainder of the keyword is an underscore character followed by the unique name of the data item. For example, the focal length of the OSIRIS NAC is specified by INS-226111_FOCAL_LENGTH 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 [6]: OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) is a dual camera imaging system operating in the visible, near infrared and near ultraviolet wavelength ranges. OSIRIS consists of two independent cameras sharing common electronics. The Narrow Angle Camera (NAC) is designed to produce high spatial resolution images of the nucleus of the target comet. The Wide Angle Camera (WAC) has a wide field of view and high straylight rejection to image the dust and gas directly above the surface of the nucleus of the target comet. Each camera is equipped with filter wheels to allow selection of imaging wavelengths for various purposes. The spectroscopic and wider band infrared imaging capabilities originally proposed and incorporated in the instrument name were descoped during development. A description of the OSIRIS cameras can be found in [5]. Please note that the optical parameters of NAC and WAC are different for geometric distortion uncorrected (CODMAC level 2 and 3) or corrected images (CODMAC level 4). In case of geometric distortion UNCORRECTED images, the optical parameters vary pixel by pixel. Summary of nominal OSIRIS characteristics: Wavelength range (nm): Wide Angle Camera -- 240 - 720 Narrow Angle Camera -- 250 - 1000 Optical design: Wide Angle Camera -- Two mirror off axis Narrow Angle Camera -- Three mirror off axis F-ratio: Wide Angle Camera -- 5.6 Narrow Angle Camera -- 8.0 Mass (including harness, kg): 34.4 Power consumption (maximum, W): 57.2 Mounting Alignment -------------------------------------------------------- Refer to the latest version of the Rosetta Frames Definition Kernel (FK) [4] for the OSIRIS reference frame definitions and mounting alignment information. Apparent FOV Layout -------------------------------------------------------- This section provides a diagram illustrating the OSIRIS NAC and WAC apparent FOV layout in the standard Rosetta orientation. Details about the image orientation can be found in [6]. WAC Apparent FOV: ~~~~~~~~~~~~~~~~~ ^ +Xsc (sagittal) | +Xwac | +---------|---------+ | | | ^ | | | | | | | +Ywac | 2048 | x-------------> | Line lines | +Zsc | +Ysc | display | (tangential) | direction | | | | | | +-----------------(0,0) 2048 pixels/line <------------------ Sample display direction Boresight (+Z axis) is into the page NAC Apparent FOV: ~~~~~~~~~~~~~~~~~ ^ +Xsc (sagittal) | +Xnac | +---------|---------+ | | | ^ | | | | | | | +Ynac | 2048 | x-------------> | Line lines | +Zsc | +Ysc | display | (tangential) | direction | | | | | | (0,0)-----------------+ 2048 pixels/line -----------------> Sample display direction Boresight (+Z axis) is into the page Optical Parameters -------------------------------------------------------- The optical parameters are defined for nominal (non geometric distortion corrected) and geometric distortion corrected OSIRIS NAC and WAC images. For the non geometric distortion corrected images, different focal lengths and IFOV for the sagittal and tangential pitches are defined and thus Focal Length and IFOV are provided as two element vectors. For the geometric distortion corrected images, same focal length and IFOV values for the sagittal and tangential pitches are provided in two element vectors to make dimensions of similar keywords consistent across the IK. It needs to be noted different focal lengths in different directions is only an optical effect: The CCD pixels are squares, not rectangles. Moreover, it must be remembered that for non-distortion corrected data the focal length and the IFOV vary over the Field-of-View. The values reported here are the one for the reference pixel. Non Geometric Distortion Corrected: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The following OSIRIS NAC and WAC nominal (non geometric distortion corrected) optical parameters are included in the data section below, from [3], [6] and [7]: ----------------------------------------------------------- parameter NAC WAC ----------------------------------------------------------- f/ratio f/8 f/5.6 Focal Length, mm Sagittal 712.396 139.9579 Tangential 721.124 131.4013 IFOV, rad/pixel Sagittal 18.950E-06 96.457E-06 Tangential 18.721E-06 102.74E-06 Field of view (deg) Sagittal (+Xsc) 2.22 11.35 Tangential (+Ysc) 2.20 12.11 --------------------------------------------------------- The keywords below provide nominal data for both cameras. Angular size values in the keywords are given in radians, with the Sagittal size being the first value and the Tangential size being the second value in each pair. \begindata INS-226111_F/RATIO = ( 8.0 ) INS-226111_FOCAL_LENGTH = ( 712.396, 721.124 ) INS-226111_IFOV = ( 0.000018950, 0.000018721 ) INS-226111_FOV_ANGULAR_SIZE = ( 0.038746309, 0.038397243 ) INS-226112_F/RATIO = ( 5.6 ) INS-226112_FOCAL_LENGTH = ( 139.9579, 131.4013 ) INS-226112_IFOV = ( 0.000096457, 0.00010274 ) INS-226112_FOV_ANGULAR_SIZE = ( 0.198094870, 0.211359372 ) \begintext Geometric Distortion Corrected: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The following OSIRIS NAC and WAC geometrical distortion corrected optical parameters are included in the data section below, from [3], [6] and [7]: ----------------------------------------------------------- parameter NAC WAC ----------------------------------------------------------- f/ratio f/8 f/5.6 Focal Length, mm 717.322 135.68 IFOV, rad/pixel 18.820E-06 99.499E-6 Field of view (deg) Sagittal (+Xsc) 2.21 11.68 Tangential (+Ysc) 2.21 11.68 ----------------------------------------------------------- The keywords below provide nominal data for both cameras. Angular size values in the keywords are given in radians, with the Sagittal size being the first value and the Tangential size being the second value in each pair. \begindata INS-226113_F/RATIO = ( 8.0 ) INS-226113_FOCAL_LENGTH = ( 717.322, 717.322 ) INS-226113_IFOV = ( 0.00001881999, 0.00001881999 ) INS-226113_FOV_ANGULAR_SIZE = ( 0.038571776, 0.038571776 ) INS-226114_F/RATIO = ( 5.6 ) INS-226114_FOCAL_LENGTH = ( 135.68, 135.68 ) INS-226114_IFOV = ( 0.0000994991, 0.0000994991 ) INS-226114_FOV_ANGULAR_SIZE = ( 0.203854456, 0.203854456 ) \begintext CCD Parameters -------------------------------------------------------- NAC and WAC use the CCD detector of the same type with the following nominal geometry parameters, from [6]: ---------------------------------------------- parameter value ---------------------------------------------- Pixel Size, microns Sagittal 13.5 Tangential 13.5 Detector Array Size, pixels Sagittal 2048 Tangential 2048 Detector Array Center, pixels Sagittal 1023.5 Tangential 1023.5 ---------------------------------------------- The values are given in microns for PIXEL_SIZE keywords and in counts for PIXEL_SAMPLES, PIXEL_LINES, and CENTER keywords. The values apply to both geometric distortion corrected and non corrected images. \begindata INS-226111_PIXEL_SIZE = ( 13.5, 13.5 ) INS-226111_PIXEL_SAMPLES = ( 2048 ) INS-226111_PIXEL_LINES = ( 2048 ) INS-226111_CCD_CENTER = ( 1023.5, 1023.5 ) INS-226112_PIXEL_SIZE = ( 13.5, 13.5 ) INS-226112_PIXEL_SAMPLES = ( 2048 ) INS-226112_PIXEL_LINES = ( 2048 ) INS-226112_CCD_CENTER = ( 1023.5, 1023.5 ) INS-226113_PIXEL_SIZE = ( 13.5, 13.5 ) INS-226113_PIXEL_SAMPLES = ( 2048 ) INS-226113_PIXEL_LINES = ( 2048 ) INS-226113_CCD_CENTER = ( 1023.5, 1023.5 ) INS-226114_PIXEL_SIZE = ( 13.5, 13.5 ) INS-226114_PIXEL_SAMPLES = ( 2048 ) INS-226114_PIXEL_LINES = ( 2048 ) INS-226114_CCD_CENTER = ( 1023.5, 1023.5 ) \begintext Filter Parameters --------------------------------------------------------------------------- 12 filters for the NAC and 14 for the WAC were selected. The NAC filters are used to characterize the reflectivity spectrum of the nucleus surface over as wide a spectral range as possible, and to focus in particular on some possible or likely absorption bands. With no need for isolating narrow spectral features, the bandpasses are generally wider than for the WAC, i.e. typically from 24 to 100 nm. For the WAC, the principal aim is to study the intensity of gas emissions and dust-scattered sunlight as functions of position and viewing angle in the vicinity of the nucleus. This is accomplished by centering narrow bandpass filters on a set of emission lines with slightly broader bandpass filters to measure the continuum. Details about the filters available in each camera can be found in [5]. FOV Definitions --------------------------------------------------------------------------- This section contains definitions for the OSIRIS NAC and WAC nominal and distortion corrected FOVs. These definitions are provided in the format required by the SPICE (CSPICE) function GETFOV (getfov_c). NAC FOV: ~~~~~~~~ The set of assignments in the data section below defines the NAC FOV for non-geometric distortion corrected images with respect to the ROS_OSIRIS_NAC frame to be a rectangle with the corners defined by the first and last pixels of the first and last lines of the CCD and the boresight along the +Z axis of the ROS_OSIRIS_NAC frame. This FOV definition uses angular extent style specification with the sagittal and tangential angular sizes taken from the ``Optics Parameters'' section above. \begindata INS-226111_FOV_FRAME = 'ROS_OSIRIS_NAC' INS-226111_FOV_SHAPE = 'RECTANGLE' INS-226111_BORESIGHT = ( 0.000000 0.000000 1.000000 ) INS-226111_FOV_CLASS_SPEC = 'ANGLES' INS-226111_FOV_REF_VECTOR = ( 1.000000 0.000000 0.000000 ) INS-226111_FOV_REF_ANGLE = ( 1.1118 ) INS-226111_FOV_CROSS_ANGLE = ( 1.0984 ) INS-226111_FOV_ANGLE_UNITS = 'DEGREES' \begintext WAC FOV: ~~~~~~~~ The set of assignments in the data section below defines the WAC FOV for non-geometric distortion corrected images with respect to the ROS_OSIRIS_WAC frame to be a rectangle with the corners defined by the first and last pixels of the first and last lines of the CCD and the boresight along the +Z axis of the ROS_OSIRIS_WAC frame. This FOV definition uses angular extent style specification with the sagittal and tangential angular sizes taken from the ``Optics Parameters'' section above. \begindata INS-226112_FOV_FRAME = 'ROS_OSIRIS_WAC' INS-226112_FOV_SHAPE = 'RECTANGLE' INS-226112_BORESIGHT = ( 0.000000 0.000000 1.000000 ) INS-226112_FOV_CLASS_SPEC = 'ANGLES' INS-226112_FOV_REF_VECTOR = ( 1.000000 0.000000 0.000000 ) INS-226112_FOV_REF_ANGLE = ( 5.659 ) INS-226112_FOV_CROSS_ANGLE = ( 6.027 ) INS-226112_FOV_ANGLE_UNITS = 'DEGREES' \begintext NAC Geometric Distortion Corrected FOV: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The set of assignments in the data section below defines the NAC FOV for Geometric Distortion Corrected images with respect to the ROS_OSIRIS_NAC frame to be a square with the corners defined by the first and last pixels of the first and last lines of the CCD and the boresight along the +Z axis of the ROS_OSIRIS_NAC frame. This FOV definition uses angular extent style specification with the sagittal and tangential angular sizes taken from the ``Optical Parameters'' section above. \begindata INS-226113_FOV_FRAME = 'ROS_OSIRIS_NAC' INS-226113_FOV_SHAPE = 'RECTANGLE' INS-226113_BORESIGHT = ( 0.000000 0.000000 1.000000 ) INS-226113_FOV_CLASS_SPEC = 'ANGLES' INS-226113_FOV_REF_VECTOR = ( 1.000000 0.000000 0.000000 ) INS-226113_FOV_REF_ANGLE = ( 1.1041 ) INS-226113_FOV_CROSS_ANGLE = ( 1.1041 ) INS-226113_FOV_ANGLE_UNITS = 'DEGREES' \begintext WAC Distortion Corrected FOV: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The set of assignments in the data section below defines the WAC FOV for Geometric Distortion Corrected images with respect to the ROS_OSIRIS_WAC frame to be a square with the corners defined by the first and last pixels of the first and last lines of the CCD and the boresight along the +Z axis of the ROS_OSIRIS_WAC frame. This FOV definition uses angular extent style specification with the sagittal and tangential angular sizes taken from the ``Optical Parameters'' section above. \begindata INS-226114_FOV_FRAME = 'ROS_OSIRIS_WAC' INS-226114_FOV_SHAPE = 'RECTANGLE' INS-226114_BORESIGHT = ( 0.000000 0.000000 1.000000 ) INS-226114_FOV_CLASS_SPEC = 'ANGLES' INS-226114_FOV_REF_VECTOR = ( 1.000000 0.000000 0.000000 ) INS-226114_FOV_REF_ANGLE = ( 5.838 ) INS-226114_FOV_CROSS_ANGLE = ( 5.838 ) INS-226114_FOV_ANGLE_UNITS = 'DEGREES' \begintext Optical Distortion -------------------------------------------------------- For the optical distortion and geometric distortion corrections applied to OSIRIS NAC and WAC data see documentation in the OSIRIS PDS archives. Platform ID --------------------------------------------------------------------------- This number is the NAIF instrument ID of the platform on which the cameras are mounted. For both cameras this platform is the spacecraft. \begindata INS-226111_PLATFORM_ID = ( -226000 ) INS-226112_PLATFORM_ID = ( -226000 ) INS-226113_PLATFORM_ID = ( -226000 ) INS-226114_PLATFORM_ID = ( -226000 ) \begintext End of IK file.