SSIES, or the Special Sensors-Ions, Electrons, and Scintillation thermal plasma analysis package is a suite of instruments built by the William B. Hanson center for Space Sciences at the University of Texas at Dallas and flown on a number of the
DMSP satellites. SSIESS includes a Retarding Potential Analyzer (RPA), and Ion Drift meter (IDM), a scintillation meter, and a
Langmuir probe
A Langmuir probe is a device used to determine the electron temperature, electron density, and electric potential of a plasma. It works by inserting one or more electrodes into a plasma, with a constant or time-varying electric potential between ...
.
References
UTD SSIES Homepage
Space science experiments
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