File: AAREADME.TXT                                Version: 11/15/2001 JFC
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The Pioneer 10 spacecraft was launched from Earth in March 1972 for an
encounter with Jupiter in Dec. 1973, thereafter following a solar system 
escape trajectory near the Ecliptic. As of March 1998 the spacecraft was 
still operational and being tracked occasionally, although the Pioneer 
Project officially terminated on March 31, 1997. The file 
PIONEER10_NMC.txt includes information extracted from the NSSDC Master 
Catalog about this mission and the onboard experiments. 

The following table gives the dates, times, and jovian radii (1 Rj = 
71,492 km) when Pioneer 10 first entered and last existed the 
magnetosphere of Jupiter, these being the intervals for which 
interplanetary data are not available. 

   Event  Year/Day/Time      Radius    Year-Month-Day

   Entry  1973/330/19:46    108.9 Rj   1973-11-26
   Exit   1973/356/19:28    242.6 Rj   1973-12-22

The following subdirectories include data and information for various
experiments and datatypes as indicated:

MAG - Helium Vector Magnetometer (HVM) Experiment, Jet Propulsion 
      Laboratory

PLASMA - Plasma Analyzer (PA) Experiment, NASA Ames Research Center

MERGED - Merged and hourly averaged interplanetary solar wind plasma, 
         magnetic field, and spacecraft trajectory data set compiled by 
         NSSDC

OPTICAL - Zodiacal light data set documentation

PARTICLE - four energetic particle/cosmic ray experiments (CPI, CRT, GTT, 
           TRD)

UV - Ultraviolet Photometer Experiment, University of Southern California

TRAJ - spacecraft ephemeris data sets from the Pioner Project at NASA 
       Ames Research Center and NSSDC's Satellite Situation Center (SSC)


Related Information and Data:

Further details on the spacecraft, experiment, data sets at NSSDC, and 
related WWW sites can be found on the Pioneer 10/11 flight project page 
under

http://nssdc.gsfc.nasa.gov/space/

Hour averages of the interplanetary trajectory and solar wind data may be 
also be accessed and plotted on-line through the COHOWeb service based at 
the same WWW site as above. Access to the Satellite Situation Center (SSC) 
service for heliocentric coordinates from Pioneer, Voyager, Ulysses, and 
other spacecraft operating in interplanetary space is also provided from 
this site. The SSC maintains extensive data bases of orbital elements and 
cartesian coordinates for many earth-orbiting and interplanetary science 
spacecraft.

Acknowledgement:

Use of these data in publications should be accompanied at minimum by
acknowledgements of the National Space Science Data Center and the 
responsible Principal Investigator defined in the experiment documentation 
provided here.