BackForwardInstrument:  SMS 

Instrument details
Acronym SMS
Full name Solar wind ion composition, Mass sensor, and Suprathermal ion composition
Purpose To determine the abundance, velocity, spectra, temperature, and thermal speeds of solar-wind ions entering the Earth's magnetosphere
Short description Assemblage of five separate packages mounted on the spacecraft body, to measure: energy, mass and charge composition of major solar wind ions from H to Fe, over the energy range from 0.5 to 30 keV/e; high mass-resolution elemental and isotopic composition of solar wind ions from He to Ni, having energies from 0.5 to 12 keV/e; composition, charge state and 3-D distribution functions of suprathermal ions (H to Fe) over the energy range from 8 to 230 keV/e
Background Part of a package of instruments to observe the solar wind
Scanning Technique Interplanetary space observation from the L1 Lagrange libration point
Resolution N/A
Coverage / Cycle Nearly full interplanetary space
Mass Power Data Rate

 

Providing Agency NASA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 1995 to 2024
Last update: 2021-11-10
Detailed characteristics
Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Solar and space environment monitors
  • Energetic particle spectrometer
WIGOS Subcomponents
  • Subcomponent 1
  • Solar wind in situ plasma and energetic particles, magnetic field, at L1
  • Solar wind at L1 - Proton sensor
  • Solar wind at L1 - Alpha-particle sensor
  • Solar wind at L1 - Heavy ion sensor
  • Solar wind at L1 - Plasma density sensor
  • Solar wind at L1 - Plasma temperature sensor
  • Solar wind at L1 - Plasma velocity sensor
Mission objectives
Primary mission objectives
  • Alpha particles differential directional flux
  • Heavy ion flux energy and mass spectrum
  • Proton differential directional flux
Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
Note: * Primary mission objective.
VariableRelevance for measuring this variableOperational limitationsExplanation
Proton differential directional flux*3 - highNo specific limitation.Interplanetary space, low and medium energy (up to 1000 keV)
Alpha particles differential directional flux*2 - very highNo specific limitation.Interplanetary space. Low-medium energy range (<10 up to 100 MeV/n)
Solar wind density3 - highNo specific limitation.Interplanetary space. Inferred from Proton and Alpha-particle spectroscopy
Solar wind temperature3 - highNo specific limitation.Interplanetary space. Inferred from Proton and Alpha-particle spectroscopy
Solar wind velocity3 - highNo specific limitation.Interplanetary space. Inferred from Proton and Alpha-particle spectroscopy
Heavy ion flux energy and mass spectrum*4 - fairNo specific limitation.Interplanetary space. Low-medium energy range (<10 up to 100 MeV/n)