Plasma laboratory simulations of Titan's aerosols

Titan, the biggest satellite of Saturn, have a dense atmosphere mainly composed of N2 and a few amount of CH4. High energy solar photons and electrons from the magnetosphere of Saturn generate a wide range of organic species from simple volatiles to organic solid particles. All around Titan, a dense and opaque brown aerosol layers prevents the observation of the soil. To get more information on Titan's atmosphere, the Cassini-Huygens space probes launched in 1997 and the Huygens module descend in the atmosphere of Titan on the 14th January 2005.Before the Cassini-Huygens program, laboratory simulation approach was already initiated for the production of analogues of Titan's aerosols, named 'tholins'. Different types of plasmas have been used. Elementary analysis of 'tholins' have also been done. From plasma modelling, the Electron Energy Distribution Function is calculated and compared to the solar energy spectrum. Some results on composition of tholins produced in RF plasmas are presented: morphology from MEB observation, elemental composition. A tentative of correlation between plasma properties and tholins composition is done