Free Astronomy Magazine May-June 2016

ASTRONAUTICS to map atmospheric methane (as well as water vapour, nitrogen oxides, acetylene and other molecules) with a level of sensi- tivity 1,000 times greater that previously available to researchers. This will allow to more precisely locate the areas in which methane is being released into the atmo- sphere, when it is released and if such re- lease is associated with certain geological structures or if it is concurrent with certain phenomena. A possible territorial coinci- dence between methane springs and un- derground water ice deposits would sup- port the hypothesis that at the origin of that gas there are contemporary life forms. This does not mean, however, that the TGO will be able to directly confirm the exis- tence of microscopic Martians, but may nevertheless indicate which sites have the highest probability of hosting them. Once identified the most promising envi- ronments, it will be up to the second mis- sion to verify if the intriguing methane traces are the product of some biological processes or not. ExoMars 2018 (or 2020) will consist of a large lander, formed by a stationary platform equipped with a suite of scientific instruments for the study of the internal structure of Mars and by an automated rover that propels itself across the planet's surface. Inside the rover will be housed a true exo- biological laboratory, capable of analyzing soil samples and identify, if present, biosi- gnatures of past or present life forms. Thanks to a special drill, the rover will be able to bore up to 2 metres into the Mar- tian surface and extract materials belong- ing to that particular frozen substrate con- sidered by many scientists as the ideal hab- itat for possible microbial colonies which have survived to the present day. If by 2022, year in which the dual mission is expected to be concluded, ExoMars has not produced significant results in the lim- ited areas that it will explore, this does not necessarily mean that Mars has always been lifeless, but at that point it is clear that finding traces of life within a short time will be extremely difficult. A flight model of Schiapa- relli photographed during prepara- tion for thermal vacuum testing. [ESA – B. Bethge] n