DLR WB-RS Up Plan.phys. SESAME

(German Version)


      'Permittivity Probe'      

Primary Investigator: H. Laakso, FMI Helsinki.

(PP Scheme) The Permittivity Probe performs an electrical examination of the cometary surface layer. Two electrodes, fixed to two of the Lander's feet, are used to inject a current into the surface. Then, the electrical potential between two other electrodes is measured. This investigation is done in a frequency range up to 10 kHz and is very sensitive to changes of the permittivity of the surface material.

The permittivity changes with the abundance of polar molecules, i.e. especially water. Thus, the content and loss of water in the cometary surface material can be determined, which is assumed to vary at different distances to the sun, also with the comet's 'daytime'. This will help us to learn more of the chemical composition of the entire comet and it's behaviour in loosing his volatile material to open space.

[ Deutsch | Planetary Physics | SESAME | CASSE | DIM ]

12/07/98, Michael Kretschmer , DLR , Institute of Space Simulation , D-51170 Cologne , Germany