Experimental laboratory simulation of Titan's atmosphere: aerosols and gasphase

The discovery that Titan, the largest satellite of Saturn, has an atmospher e and that methane is a significant constituent of it, was the starting poi nt for a systematic study of Titan's atmospheric organic chemistry. Since t hen, the results from numerous ground-based observations and two flybys of Titan, by Voyager I and II, have led to experimental laboratory simulation studies and photochemical and physical modeling. All these works have provi ded a more detailed picture of Titan. We report here a continuation of such a study performing an experimental laboratory simulation of Titan's atmosp heric chemistry, and considering the two physical phases involved: gases an d aerosols. Concerning the gaseous phase, we report the first detection of C4N2 and we propose possible atmospheric abundances for 70 organic compound s on Titan's upper atmosphere. Concerning the solid phase, we have characte rized aerosol analogues synthesized in conditions close to those of Titan's environment, using elemental analysis, pyrolysis, solubility studies and i nfrared spectroscopy. (C) 1999 Elsevier Science Ltd. All rights reserved.