General information about SPICE I-kernels                                     
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   In the SPICE system, I-kernels contains instrument parameters such as      
   field-of-view size, shape, and orientation, timing information, detector   
   and filter attributes, etc.                                                
                                                                              
   The data contained in I-kernel files can be accessed and manipulated by    
   subroutines which are part of the SPICE library, the major component of the
   SPICE toolkit. The SPICE subroutines can be integrated into user           
   application programs. For information on the SPICE toolkit and/or how to   
   obtain it, please consult SPICE_INST.CAT and SOFT.CAT.                     
                                                                              
   Refer to the KERNEL.REQ document provided with the Toolkit to get more     
   information on how to access I-kernel data.                                
                                                                              
Venus Express IK Files                                                        
======================                                                        
                                                                              
   This file describes the contents of the DATA/IK directory of the Venus     
   Express SPICE dataset.                                                     
                                                                              
   All these IK files are produced manually with the information supplied by  
   Venus Express teams describing the science instruments.                    
                                                                              
   All IK files (*.TI) contained in this directory are UNIX text files. In    
   order to be used in a non-UNIX environment, they have to be converted to   
   the appropriate end-line convention. For example, the lines have to be     
   terminated by a <CR><LF> combination for Windows platforms.                
                                                                              
Venus Express I-Kernels Contained in this Data Set                            
==================================================                            
                                                                              
   The following I-kernels are provided in this data set (vv refers to the    
   version of the kernel):                                                    
                                                                              
       VEX_ASPERA4_Vvv.TI  ASPERA instrument kernel, containing instrument    
                           parameters for ASPERA.                             
                                                                              
       VEX_MAG_Vvv.TI      MAG instrument kernel, containing instrument       
                           parameters for MAG.                                
                                                                              
       VEX_PFS_Vvv.TI      PFS instrument kernel, containing instrument       
                           parameters for PFS.                                
                                                                              
       VEX_SOIR_Vvv.TI     SOIR instrument kernel, containing instrument      
                           parameters for SOIR.                               
                                                                              
       VEX_SPICAV_Vvv.TI   SPICAV instrument kernel, containing instrument    
                           parameters for SPICAV.                             
                                                                              
       VEX_VIRTIS_Vvv.TI   VIRTIS instrument kernel, containing instrument    
                           parameters for VIRTIS.                             
                                                                              
       VEX_VMC_Vvv.TI      VMC instrument kernel, containing instrument       
                           parameters for VMC.                                
                                                                              
                                                                              
   Note that the kernels are put in the data set when they are created by the 
   Instrument Teams. Therefore, some kernels might be missing at the time this
   release of the dataset is made public.                                     
                                                                              
   In the case that several versions of the same instrument kernel are        
   provided, the most recent one supersedes the other versions.               
                                                                              
Kernel file details                                                           
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   The most detailed description of the data in an IK file is provided in     
   meta data included inside the description area of the file. This           
   information can be viewed using any text editor program.                   
                                                                              
   At least a basic knowledge of the SPICE system is needed in                
   order to use this kernels. The SPICE toolkit provides versions             
   in FORTRAN (SPICELIB), C (CSPICE), IDL (icy) and Matlab (mice), and        
   the user can choose any one that suits him/her.                            
                                                                              
   The SPICELIB routine FURNSH, CSPICE function furnsh_c, and icy/mice        
   routine cspice_furnsh load a kernel file into the kernel pool              
   as shown below.                                                            
                                                                              
      CALL FURNSH( 'kernel_name' )                                            
      furnsh_c( ''kernel_name'' );                                            
      cspice_furnsh, 'kernel_name'                                            
      cspice_furnsh( 'kernel_name' );                                         
                                                                              
   In the case when two or more files contain data overlapping in             
   time for a given object, for binary kernels, the file loaded               
   last takes precedence.                                                     
                                                                              
   If two (or more) text kernels assign value(s) using the '='                
   operator to identical keywords, the data value(s) associated               
   with the last loaded occurrence of the keyword are used -all               
   earlier values have been replaced with the last loaded                     
   value(s).