File: VY2TRJ_SSC_FMT.txt                   Version: NSSDC 11/15/2001 JFC
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 Voyager 2 Interplanetary Cruise Trajectory Data from the NSSDC Satellite
 Situation Center (SSC) - Daily Values for 1977 to 2005

 Date Coverage: 1977-08-25 to 2005-01-09

 Data Contact: R. P. (Sardi) Parthasarathy
               Hughes STX Corporation / Space Physics Data Facility
               Code 632
               NASA Goddard Space Flight Center
               Greenbelt, Maryland
               sardi@nssdca.gsfc.nasa.gov
               Phone: (301) 286-8105

 Data File: VY2TRJ_SSC_1D.asc 

 Parameter Format:

 YY DDD  RAD.AU  SECLAT  SECLON  HELLAT  HELLON  HILLON

 YY = YEAR
 DDD= INTEGER DAY OF YEAR (1= JAN. 1)
 RAD.AU= HELIOSPHERIC RADIAL DISTANCE IN AU
 SECLAT= SOLAR ECLIPTIC LATITUDE IN DEGREES
 SECLON= SOLAR ECLIPTIC LONGITUDE IN DEGREES
 HELLAT= SOLAR HELIOGRAPHIC LATITUDE IN DEGREES
 HELLON= SOLAR HELIOGRAPHIC LONGITUDE IN DEGREES
 HILLON= SOLAR HELIOGRAPHIC INERTIAL LONGITUDE IN DEGREES WITH RESPECT TO
         ASCENDING NODE OF SOLAR EQUATOR ON THE ECLIPTIC


 Data Source:

 These data were obtained from running the program HELICOOR in the public
 directory NSSDCA::ANON_DIR:[ACTIVE.HELIO]. These data are based on 
 predicted trajectories calculated with the GTDS code by the NSSDC 
 Satellite Situation Center and converted to solar ecliptic and 
 heliographic coordinates by the HELIOCOOR program. The HELICOOR code was 
 written by R. Parthasarathy. The program GENTRJCON added the HILLON 
 longitude.

 Note that the solar ecliptic coordinates are given with respect to true
 equinox and ecliptic of date. The solar ascending node was located at
 ecliptic longitude +74.367 degrees as of 1 Jan. 1900 at 1200 UT; this
 longitude increases by 1.4 degrees/century.

 Warning: earlier verions of this data set had errors after 1989 and 
 should be deleted.  2/7/95 JFC


 Related Information and Data:

 Further details on the spacecraft, experiment, data sets at NSSDC, and 
 related WWW sites can be found on the Voyager 1/2 flight project page 
 under

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

 Hour averages of the interplanetary solar wind data from, and hourly 
 heliocentric coordinates of, Voyager 1/2 and other interplanetary 
 spacecraft may be also be accessed and plotted on-line through the 
 COHOWeb service based at the same WWW site as above.

 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.