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Availability: Archived at NSSDC, accessible from elsewhere

Time span: 1977-09-05 to 1989-12-31


This description was generated automatically using input from the Planetary Data System.

Data Set Overview ================= This dataset contains Voyager 1 magnetometer data from the interplanetary cruise averaged to 48 second samples in Heliographic coordinates. Data Processing =============== The high resolution data submitted to the NSSDC has its origins in the original MVS 'Summary' data sets formally produced on the NSSC IBM MVS mainframe system. The original data sets contain a mix of engineering, electron, magnetic field and plasma data. The Voyager magnetometer (MAG) experiment now resides on a dedicated workstation where only MAG data are processed. All Voyager MAG data submitted to the NSSDC consists wholly of high resolution LFM averages. These files consist of a set of averages applied across all of the mission's differing telemetry modes. In the case of the Magnetometer Experiment, the records contain both 1.92 second, 9.6 second and 48 second averages. 1.92 second averages are created from the detail detail data, 9.6 second averages are created from 1.92 second averages and 48 second averages are created from the 9.6 second averages. All data in this NSSDC data set are interplanetary and in heliographic coordinates (see below). An ASCII formated data set containing key components of the 48 second magnetic field data and ephemeris data has been created allowing more convenient access to high resolution Voyager magnetometer data. Coordinate System ================= Interplanetary magnetic field studies make use of two important coordinate systems, the Inertial Heliographic (IHG) coordinate system and the Heliographic (HG) coordinate system. The IHG coordinate system is use to define the spacecraft's position. The IHG system is defined with its origin at the Sun. There are three orthogonal axes, X(IHG), Y(IHG), and Z(IHG). The Z(IHG) axis points northward along the Sun's spin axis. The X(IHG) - Y(IHG) plane lays in the solar equatorial plane. The intersection of the solar equatorial plane with the ecliptic plane defines a line, the longitude of the ascending node, which is taken to be the X(IHG) axis. The X(IHG) axis drifts slowly with time, approximately one degree per 72 years. Magnetic field orientation is defined in relation to the spacecraft. Drawing a line from the Sun's center (IHG origin) to the spacecraft defines the X axis of the HG coordinate system. The HG coordinate system is defined with its origin centered at the spacecraft. Three orthogonal axes are defined, X(HG), Y(HG), and Z(HG). The X(HG) axis points radially away from the Sun and the Y(HG) axis is parallel to the solar equatorial plane and therefore parallel to the X(IHG)-Y(IHG) plane too. The Z(HG) axis is chosen to complete the orthonormal triad. An excellent reference guide with diagrams explaining the IHG and HG systems may be found in Space and Science Reviews, Volume 39 (1984), pages 255-316, MHD Processes in the Outer Heliosphere, L. F. Burlaga [BURLAGA1984]. Data Format =========== field descriptor ----- ---------1. s/c identification (FLT1=Voyager 1) (FLT2=Voyager 2) 2. coordinate system (HG=heliographic)used for this data set 3. Time (UTC) format YY DDD HH MM SS MSS YY = year DDD = day of year HH = hour MM = minute SS = second MSS = millisecond 4. field magnitude (nT) 5. field component 1 (nT) - HG 6. field component 2 (nT) - HG 7. field component 3 (nT) - HG 8. spacecraft radial distance (AU) 9. spacecraft x position (AU) - IHG 10. spacecraft y position (AU) - IHG 11. spacecraft z position (AU) - IHG Contact Information =================== Principal Investigator: Prof. Norman F. Ness Bartol Research Institute Univerity of Delaware Newark, Delaware 19716-4793 Phone: (302) 831-8116 Fax: (302) 831-1843 Email: 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.

These data are available on-line from the Planetary Data System (PDS) at:

Alternate Names



  • Planetary Science: Fields and Particles

Additional Information



Questions and comments about this data collection can be directed to: Dr. Edwin V. Bell, II



NameRoleOriginal AffiliationE-mail
Dr. Norman F. NessData ProviderUniversity of Delaware
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