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Space Environment Monitor (SEM)

NSSDCA ID: 1981-059A-04

Mission Name: NOAA 7
Principal Investigators:Dr. Herbert H. Sauer
Principal Investigators:Dr. Harold Leinbach
Principal Investigators:Dr. David S. Evans


The Space Environmental Monitor (SEM) experiment was an extension of the solar-proton monitoring experiment flown on the ITOS spacecraft series. The objective was to measure proton flux, electron flux density, and energy spectrum in the upper atmosphere. The experiment package consisted of three detector systems and a data processing unit. The medium energy proton and electron detector (MEPED) measured protons in five energy ranges from 30 keV to >2.5 MeV; electrons above 30, 100, and 300 keV; protons and electrons (inseparable) above 6 MeV; and omni-directional protons above 16, 36, and 80 MeV. The high-energy proton and alpha telescope (HEPAT), which had a 48-deg viewing cone, viewed in the anti-earth direction, and measured protons in four energy ranges above 370 MeV and alpha particles in two energy ranges above 850 MeV/nucleon. The total energy detector (TED) measured electrons and protons between 300 eV and 20 keV.

Alternate Names

  • SEM


  • Space Physics: Ionospheric Studies

Additional Information

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



NameRoleOriginal AffiliationE-mail
Dr. David S. EvansPrincipal InvestigatorNOAA Environmental Research
Dr. Harold LeinbachPrincipal InvestigatorNOAA Environmental Research Laboratories
Dr. Herbert H. SauerPrincipal InvestigatorNOAA Environmental Research
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