BackForwardInstrument:  IMPACT/SEP 

Instrument details
Acronym IMPACT/SEP
Full name IMPACT / Solar Energetic Particles
Purpose Observation of solar electrons, protons and heavier ions
Short description Package of 4 separate instruments to measure electrons, protons and heavier ions from several tens of keV to approximately 100 MeV: Solar Electron Proton Telescope (SEPT), Suprathermal Ion Telescope (SIT), Low Energy Telescope (LET), High Energy Telescope (HET). Energy ranges: electrons: 20-40 keV (flux) and 0.2-5 MeV (spectrum); protons: 0.02-7 MeV (flux) and 0.02-100 MeV (spectrum); alpha-particle spectrum: 0.12-400 MeV; ions spectrum: 0.03-30 MeV/n for Z from 3 to 26
Background Part of the IMPACT (In-situ Measurements of Particles and CME Transients) instrument package
Scanning Technique Interplanetary space observation from two variable positions along the Earth’s orbit around the Sun to implement stereoscopy
Resolution N/A
Coverage / Cycle Full interplanetary spece
Mass Power Data Rate

 

Providing Agency NASA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 2007 to 2024
Last update: 2021-12-16
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 2
  • Solar wind in situ plasma and energetic particles and magnetic field off the Earth-Sun line
  • Electron sensor [at solar orbit, ecliptic, L5]
  • Proton sensor [at solar orbit, ecliptic, L5]
  • Alpha-particle sensor [at solar orbit, ecliptic, L5]
  • Heavy ion sensor [at solar orbit, ecliptic, L5]
  • Solar wind density sensor [at solar orbit, ecliptic, L5]
  • Solar wind temperature sensor [at solar orbit, ecliptic, L5]
  • Solar wind velocity sensor [at solar orbit, ecliptic, L5]
  • Subcomponent 3
  • Solar coronal magnetic field imagery, solar wind beyond L1
  • Electron sensor [from solar orbit, ecliptic, L5]
  • Proton sensor [from solar orbit, ecliptic, L5]
  • Alpha-particle sensor [from solar orbit, ecliptic, L5]
  • Heavy ion sensor [from solar orbit, ecliptic, L5]
  • Solar wind density sensor [from solar orbit, ecliptic, L5]
  • Solar wind temperature sensor [from solar orbit, ecliptic, L5]
  • Solar wind velocity sensor [from solar orbit, ecliptic, L5]
Mission objectives
Primary mission objectives
  • Alpha particles differential directional flux
  • Electron 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
Electron integral directional flux3 - highNo specific limitation.Interplanetary space, low, medium and high energy (up to over 400 keV)
Electron differential directional flux*3 - highNo specific limitation.Interplanetary space, low, medium and high energy (up to over 400 keV)
Proton integral directional flux1 - primaryNo specific limitation.Cluster flown through the magnetosphere, high energy (over 1000 keV)
Proton differential directional flux*3 - highNo specific limitation.Interplanetary space, high energy (over 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 density1 - primaryNo specific limitation.Interplanetary space. Infrerred from Proton. Electron and Alpha-particle spectroscopy
Solar wind temperature1 - primaryNo specific limitation.Interplanetary space. Infrerred from Proton. Electron and Alpha-particle spectroscopy
Solar wind velocity1 - primaryNo specific limitation.Interplanetary space. Infrerred from Proton. Electron 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)