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                   PVO-V-POS-5--VSOCOORDS-12SEC-V1.0
         PVO VENUS SC POSITION DERIVED VSO COORDINATES 12 SECOND VER1.0
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DESCRIPTION:
  This dataset contains Pioneer Venus Orbiter (PVO) spacecraft 
  position and orientation data in Venus Solar Orbital (VSO) 
  coordinates. This dataset is sampled every 12 seconds near
  periapsis, and at 1 minute or 10 minute rates in the solar wind,
  the lowest rates near apoapsis.  Planetocentric and heliocentric 
  position vectors and solar zenith angle (Sun-Venus-PVO) are also 
  provided. The VSO parameters are derived from the PVO Supplemental
  Experimenter Data Records (SEDR), other parameters are taken
  directly from the SEDR dataset.
  
  
                  Dataset Contents
  
  column    description                              unit
    --------------------------------------------------------
  Time:     Seconds since 1966-01-01T00:00:00        second
  X VSO:    VSO-X coordinate of PVO (Rv=6050 km)     Rv
  Y VSO:    VSO-Y coordinate of PVO (Rv=6050 km)     Rv
  Z VSO:    VSO-Z coordinate of PVO (Rv=6050 km)     Rv
  Altitude: Venus Center to PVO Range minus 6050 km  km
  SZA:      Solar zenith angle                       degree
  PLONG:    Planetocentric longitude                 degree
  PLAT:     Planetocentric latitude                  degree
  SPX VSO:  PVO spin axis X component in VSO coords  N/A
  SPY VSO:  PVO spin axis Y component in VSO coords  N/A
  SPZ VSO:  PVO spin axis Z component in VSO coords  N/A
  CLAT:     Heliocentric celestial latitude          degree
  CLONG:    Heliocentric celestial longitude         degree
  ELONG:    Earth's heliocentric celestial longitude degree
  RSUN:     Sun - PVO range 1 A.U. = 149,674,000 km  AU
  
  This dataset is used by the program PVROT to transform magnetic
  field vectors from Inertial Spacecraft Coordinates (ISC) to
  VSO Coordinates. Please refer to the coordinate system template
  for definitions of these two coordinate systems.
  
CONFIDENCE_LEVEL_NOTE          
  This dataset contains parameters which are either taken directly from
  the Supplemental Experimenter Data Records (SEDR) or are derived 
  entirely from those parameters. The SEDR does contain some
  gaps, spurious values, and other problems which may cause some
  data values to be untrustworthy.
      
      NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 
                  Ames Research Center 
               Moffett Field, California 
                 PIONEER VENUS PROJECT 
                SPECIFICATION PC-456.O4 
         PIONEER VENUS:  DATA USER REQUIREMENTS 
       FOR SUPPLEMENTARY EXPERIMENTER DATA RECORDS 
                   May 15, 1976