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Ion and Electron Sensor (IES)

NSSDCA ID: 2004-006A-13

Mission Name: Rosetta
Principal Investigator:Dr. James L. Burch


The Ion and Electron Sensor (IES) is an electrostatic analyzer designed to measure ions and electrons in the solar wind and cometary plasma. The IES is part of the Rosetta Plasma Consortium (RPC) which consists of four additional instruments: the Langmuir Probe Instrument (LAP), the Fluxgate Magnetometer (MAG), the Ion Composition Analyser (ICA), and the Mutual Impedance Probe (MIP). The scientific objectives of the RPC instruments are to study inner coma structure, dynamics, and aeronomy, characterize the development of cometary activity and the formation and evolution of plasma tail, and investigate solar-wind and asteroid interaction.

The IES is mounted on the top (comet-facing) deck of the orbiter and consists of an electron analyzer mounted on top of an ion analyzer. Electrostatic angular deflection allows a 90 x 360 degree field-of-view. The charged particle optics are based on a toroidal tophat geometry. The objective of the IES is to measure ion and electron distribution functions from 3 eV/e to 30 keV/e at 4% resolution. The angular resolution for electrons is 5 x 22.5 degrees, for ions 5 x 45, and for solar wind ions 5 x 5. A 3D distribution function is obtained in 65.5 s. Onboard control is provided by the Plasma Interface Unit (PIU), a common interface to the spacecraft for the RPC experiments.

Alternate Names

  • IES
  • Rosetta/IES
  • urn:esa:psa:context:instrument:ro.rpcies

Facts in Brief

Mass: 0.989 kg
Power (avg): 1.9 W

Funding Agency

  • European Space Agency (International)


  • Planetary Science: Small Bodies
  • Planetary Science: Fields and Particles

Additional Information

Questions and comments about this experiment can be directed to: Dr. David R. Williams



NameRoleOriginal AffiliationE-mail
Dr. James L. BurchPrincipal InvestigatorSouthwest Research

Selected References

  • Trotignon, J. G., et al., The Rosetta Plasma Consortium: Technical realization and scientific aims, Adv. Space Res., 24, No. 9, 1149-1158, June 1999.
  • Carr, C., et al., RPC: The Rosetta Plasma Consortium, Space Sci. Rev., 128, 629-647, doi:10.1007/s11214-006-9136-4, 2007.
  • Burch, J. L., et al., RPC-IES: The Ion and Electron Sensor of the Rosetta Plasma Consortium, Space Sci. Rev., 128, 697-712, doi:10.1007/s11214-006-9002-4, 2007.

Other Related Data/Information

Image of EASEP

Rosetta RPC

RPC Home Page (Rosetta Plasma Consortium)

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