RPC: Rosetta Plasma Consortium
RPC, the Rosetta Plasma Consortium, is a set of five instruments sharing a common electrical and data interface with the Rosetta orbiter. The RPC instruments are designed to make complementary measurements of the plasma environment around comet
|RELATED LINK||ICA at the Swedish Institute of Space Physics|
Ion and Electron Sensor
The Ion and Electron Sensor (IES) will simultaneously measure the flux of electrons and ions in the plasma surrounding the comet over an energy range from around one electron volt, which approaches the limits of detectability, up to 22 keV. IES consists of two electrostatic analysers, one for electrons and one for ions, which share a common entrance aperture. The charged particle optics for IES employs a toroidal top-hat geometry along with electrostatic angle deflectors to achieve an electrostatically scanned field of view of 90 × 360 degrees.
The Langmuir Probe (LAP) instrument will measure the density, temperature and flow velocity of the cometary plasma. It comprises two spherical sensors mounted at the tip of deployable booms, with the sensors capable of being swept in potential to measure the current-voltage characteristic of the intervening plasma, which provides information on the electron number density and temperature. The probes can be held at a fixed bias potential to measure plasma density fluctuations and by a time-of-flight analysis of the signals from the two probes the plasma flow velocity can be determined.
|RELATED LINK||LAP at the Swedish Institute of Space Physics|
The Magnetometer experiment (MAG) will measure the magnetic field in the region where the solar wind plasma interacts with the comet. It consists of two triaxial fluxgate magnetometer sensors mounted on a 1.5 metre deployable boom that points away from the comet nucleus. One sensor is mounted near the outboard tip of the boom and one is mounted part way along the boom. The use of two sensors allows the effects of the spacecraft's own magnetic field to be minimised.
MAG will also study any magnetic field possessed by the comet nucleus, in cooperation with the ROMAP magnetometer experiment on the Rosetta lander.
|RELATED LINK||MAG at the Technical University of Braunschweig|
Mutual Impedance Probe
The Mutual Impedance Probe (MIP) will derive the electron gas density, temperature, and drift velocity in the inner coma of the comet by measuring the frequency response of the coupling impedance between two dipoles.
MIP will also investigate the spectral distribution of natural waves in the 7 kHz to 3.5 MHz frequency range and monitor the dust and gas activity of the nucleus.
Plasma Interface Unit
The Plasma Interface Unit (PIU) acts as an interface between the five instruments that make up RPC and the Rosetta spacecraft by providing a single path for the transmission of scientific and housekeeping data to the ground and for the receipt and processing of commands sent from the ground. The PIU also takes power from the spacecraft and converts, conditions and manages it for the RPC instruments.
PIU also performs on-board data processing for the MAG sensor unit, which has no data processing capability of its own.
|RELATED LINK||PIU at Imperial College|
Rosetta Blog articles
|11/11/2014||The singing comet|
|Rosetta's plasma experiments check out of commissioning|
|< Previous article: ROSINA: Rosetta Orbiter Spectrometer for Ion and Neutral Analysis||Next article: RSI: Radio Science Investigation >|