The Rosetta Lander Magnetometer and Plasma Monitor ROMAP (Rosetta Lander Magnetometer and Plasma Monitor) is a multi-sensor experiment. The magnetic field is measured with a fluxgate magnetometer. An electrostatic analyzer with integrated Faraday cup measures ions and electrons. The local pressure is measured with Pirani and Penning sensors. The sensors are situated on a short boom. The deployment on the surface of a cometary nucleus demanded the development of a special digital magnetometer of little weight and small power requirements. For the first time a magnetic sensor will be operated from within a plasma sensor. A prototype of the magnetometer, named SPRUTMAG, was flown on space station MIR.
The ROMAP experiment is developed under the leadership of the TU Braunschweig. IWF contributed an integrated control unit. As the weight of this unit was limited to 60 g, special technologies were implemented. The radiation hardness of the unit was tested at the TU-Graz in the framework of a master thesis.
The magnetometer will be exposed to extreme temperatures at the comet's surface. IWF designed a special setup that allows to calibrate the magnetometer in a wide range of temperatures. The software to test ROMAP was also developed at IWF. Because of the short boom of the Rosetta lander and the magnetic noise of the electric motors, a special magnetic cleanliness program was needed. For this, the IWF has developed the software and evaluated the test data.
During the long-term measurements at the surface of the cometary nucleus the creation of a magnetic cavity around the comet will be investigated. A possible inherent magnetic field of the cometary nucleus will be measured during the decent to and at the surface. The global electric conductivity of the nucleus can be determined with magnetic field measurements in the solar wind (RPC-MAG) and at the comet's surface (ROMAP).
Further information on ROMAP is found at TUB and MPAE.
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