Exobiology : what are the relations between our solar system and its embedded life ?
Exobiology (or astrobiology) is the science which is devoted to the study of life in the universe. This includes the study of life itself, its evolution and its distribution in the universe, but also the conditions and the processes which allowed the emergence of life on our planet, or elsewhere in the universe. Therefore, this science is obviously a pluridisciplinary one, meaning that it requires the skills from both biologists, physicists, chemists and geologists.
IPSL is involved in this field of research with the main objective to study the distribution of the organic matter, and its evolution in the solar system. These information are very important to understand how the components of life can have been put together Earth, to lead to the formation of the first living organisms by a chemical evolution. They could also allow the discovery of extraterrestrial life forms, either past (Mars ?), or present (Europa ?). It must finally underline that IPSL is involved in researches connected to exoplanets, either for their detection, or for the study of their atmospheres, that telescopes will be capable to probe in a very near future.
The methods used for these studies are essentially : (1) measurements from planetary orbits, or in situ (meaning directly in the environment studied) with instrumentation onboraded in space probes; (2) numerical modeling; (3) laboratory simulations.
The main environments studied in the frame of exobiology at IPSL are Titan, the largest plus satellite of Saturn, which hosts a dense atmosphere mainly composed of N2 and CH4; Mars, which could have evolved like the Earth during the first billion year of its existence; Phobos, the largest satellite of Mars, which is certainly an asteroid captured by the Mars gravity; and comets, which are important because they probably “imported” on Earth volatiles which compose the oceans and atmosphere of the primitive earth, but also organics which could have been involved in the prebiotic chemistry.
To conclude, IPSL is also involved in the animation of the french community implied in exobiology, through its participation to Groupe De Recherche en Exobiologie of CNRS (GdR Exobiologie), also recognised at the international level.