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Low-Energy Integral Spectrum Measurement Experiment

NSSDCA ID: 1966-058A-02

Mission Name: Explorer 33
Principal Investigator:Mr. Gideon P. Serbu


A wide-aperture, multi-grid potential analyzer was used to observe the intensity of the electron and ion components of the low-energy plasma in interplanetary space and near earth. Integral spectra were obtained for both ions and electrons in the energy ranges from 0 to 45 eV (15 steps) and 0 to 15 eV (15 steps). Complete spectra for protons and electrons were obtained every 80 s. The experiment operated until June 29, 1967. Data no longer exist.

Alternate Names

  • Explorer33/Low-EnergyIntegralSpectrumMeasurementExperiment
  • Thermal Ion Probe-Retarding Potential Analyzer(Protons, Electrons Below 45 EV)


  • Space Physics: Magnetospheric Studies
  • Space Physics: Heliospheric Studies

Additional Information

Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Dr. Eugene J. MaierOther InvestigatorNASA Goddard Space Flight Center
Mr. Gideon P. SerbuPrincipal InvestigatorNASA Goddard Space Flight Center
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