File: m10_mag_42sec_format.txt             Version: NSSDC 2003-08-13 JFC
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Mariner 10: 42-second Interplanetary Magnetic Field

NSSDC Data Set ID: 73-085A-04T

Date Coverage: 1973-11-03 to 1975-03-21

Data Source: 
   Dr. Aaron Roberts
   Code 692
   NASA Goddard Space Flight Center
   Greenbelt, MD 20771
   Phone: 301-286-5606

NSSDC Contact:
   Dr. John F. Cooper
   Code 632
   NASA Goddard Space Flight Center
   Greenbelt, MD 20771
   Phone: 301-286-1193
   E-mail: jfcooper@pop600.gsfc.nasa.gov

Description:

These data consist of 42 s average magnetic field vectors in Heliographic
RTN coordinates in ASCII format. The data are grouped into one day files
and span the time period from 1973 day 307 (Nov. 3) through 1975 day 80
(Mar. 21). 


File Formats
____________


42 s Resolution Magnetic Field


    Each file consists of ASCII records, one line per record. Each line
    consists of a two digit year, a decimal day of year (1 Jan. = Day 0),
    the radial, tangential, and normal components of the magnetic field (in
    heliographic RTN coordinates), the magnitude of the magnetic field, and
    the number of samples used to produce the 42 s average. The time given
    corresponds to the UTC start time of the 42 s average. Magnetic field
    units are nanoTelsa (1 Gauss = 100,000 nT). Thus, in the sample 
    record:

     73  306.382690 -15.77 -30.77 -19.85  39.87  684

    the record begins at 1973 day 307 at 09:11:04.416 UTC. The RTN
    components are -15.77, -30.77, and -19.85 nT , respectively. The 
    field magnitude is 39.87 nT and 684 magnetic field samples were used 
    to create the 42 s average.

    No data are available for 1973 days 361-365.


Acknowledgement:

Please acknowledge Dr. Norman F. Ness, the Principal Investigator, and
NSSDC for usage of this data set in presentations and publications.