BackForwardInstrument:  EFW (VAP) 

Instrument details
Acronym EFW (VAP)
Full name Electric Field and Waves Suite
Purpose To study the electric fields in near-Earth space that energize radiation particles and modify the structure of the inner magnetosphere
Short description A set of four spin-plane electric field antennae and a set of two spin-axis stacer booms. Dynamic range: 0.001-3 mV/m
Background Part of a package of instruments carried through the Magnetosphere crossing the Van Allen radiation belts
Scanning Technique 2 satellites moving to different positions into the Magnetosphere
Resolution N/A
Coverage / Cycle Full magnetospheric volume: sampling at 6 s intervals
Mass 9.2 kg Power 14.4 W Data Rate 2 kbps


Providing Agency NASA
Instrument Maturity Backed by strong heritage
Utilization Period: 2012 to 2019
Last update: 2021-10-02
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
  • Field or radiowave sensor
WIGOS Subcomponents
  • Subcomponent 2
  • Magnetospheric energetic particles and magnetometers
  • Electric field sensor [in LEO and cross magnetosphere]
  • Ionospheric total electron content sensor [at LEO and cross magnetosphere]
  • Ionospheric electron density sensor [in LEO and cross magnetosphere]
Mission objectives
Primary mission objectives
  • Electric Field
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
Electric Field*1 - primaryNo specific limitation.Cluster in the magnetosphere. Electric field, wide dynamic range
Ionospheric plasma density4 - fairNo specific limitation.Earth's limb. Ionospheric plasma density
Electron Density4 - fairNo specific limitation.Platform. Electron density