This directory contains the SPICE Leapseconds, Planetary Constants and Ephemeris kernels in ASCII format. True SPICE transfer format kernels have the line termination characters of the native platform. In order to convert these files to binary forms that can be loaded into SPICE routines, the ASCII must first be converted to native ASCII. Only then will "spacit" work.

The file provided here are provided for user convenience only. They are not part of the "official" archive portion on this volume. The NAIF Node of the PDS maintains the official, latest version of all PSICE products on its ftp site (naif.jpl.nasa.gov). Please verify that these kernels are up to date before using them.

SPICE SPK kernels allow computation of the position and velocity (the state vector) of any one of the 'bodies' described relative to any of the others. The state returned can be geometric (no corrections) or corrected for light time and/or stellar aberration. The state vector is returned in any of a number of inertial or body fixed reference frames, as selected by the user; examples are B1950, J2000 and IAU_JUPITER (System III). Getting state vectors, including the conversion to Jupiter System III coordinates if requested, is accomplished using NAIF Toolkit software. For more information regarding SPICE or obtaining the NAIF Toolkit, please contact Chuck Acton (INTERNET: cacton@spice.jpl.nasa.gov, PHONE: (818)354-3869) or check the PDS website's (http://pds.jpl.nasa.gov) link to the NAIF node for current NAIF contact information.

The geometry information provided on this volume only includes the SPICE SPK file (containing spacecraft and target body ephemeris). As of the date of publication of this volume, no spacecraft orientation data were available.

The PDS/NAIF node is in the process of restoring spacecraft orientation information for the SPICE pointing kernel (C-kernel). NAIF plans to make this kernel available in a future archive. For information regard the availability of the Voyager 2 SPICE C-kernel, please contact Chuck Acton as described above.

The PDS/PPI node is in the process of preparing a data set that will contain the spacecraft orientation information relevant to PRA and other Voyager instruments for which spacecraft orientation is important. This data set will be archived in a future volume. For information regarding the availability of this data set, please contact PDS Operator at the PDS/PPI node (INTERNET: pds_operator@igpp.ucla.edu, PHONE: (310) 206-6073).

                                                                         
  [EXTRAS/SPICE]                                                                  
     |                                                                        
     |- SPICEINFO.TXT  (This file) describes the contents of this             
     |                 directory.  
     |
     |                                                                        
     |- LEAPSECS.TLS  SPICE Leapseconds kernel containing a tabulation 
     |                of leapseconds, used in time conversions when 
     |                processing other SPICE files, such asSPK and PCK.
     |                                                            
     |                                                                        
     |- LEAPSECS.LBL  PDS label for LEAPSECS.TLS.
     |                                                                        
     |                                                                        
     |- PCONST.TPC    Planetary Constants kernel (PCK) providing 
     |                selected physical and cartographic constants 
     |                for planets and satellites, typically used to 
     |                convert position measurements into a body-fixed 
     |                reference frame.
     |                                                                        
     |- PCONST.LBL    PDS label for PCONST.TPC.
     |                                                                        
     |- VG2_JUP.TSP   Contains the Voyager 2 Jupiter Encounter
     |                SP Kernel in ASCII format.             
     |                                                                        
     |- VG2_JUP.LBL   PDS label for VG2_JUP.TSP.
     |                                                                        
     |
     |- [SPICEDOCS]   Contains a description of the NAIF SPICE System
     |                (SPICE) document.
     |