BackForwardInstrument:  ISIS-EPI 

Instrument details
Acronym ISIS-EPI
Full name Integrated Science Investigation of the Sun - Energetic Particle Instruments
Purpose To observe the composition of the solar atmosphere
Short description Suite of two instruments that take an inventory of elements in the sun's atmosphere using a mass spectrometer to weigh and sort ions in the vicinity of the spacecraft. Z range 1-26, energy/mass range 0.2-120 MeV/n
Background Consolidated technology
Scanning Technique Sun pointing from a solar orbit
Resolution N/A (full disk)
Coverage / Cycle Full solar disk, nearly continuous
Mass Power Data Rate

 

Providing Agency NASA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 2018 to 2025
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
  • 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
  • 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
  • Heavy ion angular flux energy and mass spectrum
  • 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*4 - fairNo specific limitation.Sun pointing, medium and high energy (over 40 to over 1000 keV)
Alpha particles differential directional flux*1 - primaryNo specific limitation.Sun-pointing. Extended energy range (<10 to >100 MeV/n)
Solar wind density3 - highNo specific limitation.Solar viewing. Inferred from Proton and Alpha-particle spectroscopy
Solar wind temperature3 - highNo specific limitation.Solar viewing. Inferred from Proton and Alpha-particle spectroscopy
Solar wind velocity3 - highNo specific limitation.Solar viewing. Inferred from Proton and Alpha-particle spectroscopy
Heavy ion flux energy and mass spectrum*3 - highNo specific limitation.Sun-pointing. Extended energy range (<10 to >100 MeV/n)
Heavy ion angular flux energy and mass spectrum*3 - highNo specific limitation.Sun-pointing. Extended energy range (<10 to >100 MeV/n)