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Magnetometer (SSM)

NSSDCA ID: 2003-048A-08

Mission Name: DMSP 5D-3/F16


The SSM is a triaxial fluxgate magnetometer designed and built at NASA Goddard Space Flight Center under the direction of Dr. Mario Acuna. A "proof-of-concept" SSM instrument was flown on the DMSP F7 spacecraft from December 1983 to late 1987. The Earth magnetic field has three sources: (1) the magnetic field from the solid earth; (2) the magnetic field from electrical currents flowing in the ionosphere and magnetosphere; and (3) the magnetic field from the spacecraft. Measurement of source 2 is the principal objective of the SSM, measurement of source 1 is a secondary objective, and measurement of source 3 is a nuisance which is eliminated from the data as much as possible during data processing. The SSM takes and reports 12 readings per second for the Y and Z axes. Only 10 of the 12 readings per second are reported for the X axis due to telemetry limitations. The axes are aligned to within 0.5 degrees with the spacecraft axes where X is downward and aligned to local vertical within 0.01 degree. Y is parallel to the velocity vector for spacecraft with ascending node in the afternoon/evening sector, and Z is away from the solar panel and anti-parallel to the orbit normal vector. Post-flight calibration can determine the mis-alignment between the instrument axes and the spacecraft axes to an accuracy of 0.1 degree/axis or better. The measurement range is ± 65535 nT for each axis, with a one-bit resolution of 2 nT. NOAA's National Geophysical Data Center maintains the data archive at

Alternate Names

  • DMSP5D-3/F16/Magnetometer_SSM_

Funding Agency

  • Department of Defense (United States)


  • Space Physics: Magnetospheric Studies

Additional Information

Questions and comments about this experiment can be directed to: Dr. Dieter K. Bilitza



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