November 27, 2017
What is an astrobiologist?
I came to Astrobiology quite early in my research. How could I miss the implications ‘Titan: the frozen Earth’, ‘organic chemistry closest to our planet’, the ‘methane cycle mimicking the water cycle on Earth’, etc. Of course, ancient Greek philosophers (them again !) had already thought of a universe consisting of “many worlds”. Thales, from Militos, and his students in the 7th century BCE argued for a Universe full of other planets, teaming with extraterrestrial life. They also proposed the idea with which we’re all familiar today (through Drake’s equation, among other and Carl Sagan’s musings, and the contributions of many other scientists’ arguments), i.e. that a Universe so full of stars must also have a large number of populated worlds. This proposal, was already defended by Epicurus and other Greek atomists who countered the geocentric models brought forward later on by Aristotle. The latter concept stuck, though, and hindered scientific progress in this domain for quite a long period of time. In 1862, the French scientist Camille Flammarion , published ‘La pluralité des mondes habités’ (‘on the plurality of inhabited worlds’), in which the conditions of habitability and the presence of life on such habitable planets of our Solar System is discussed. The public loved the book, but Urbain Le Verrier, then Director of the Paris Observatory , and many of his colleagues completely rejected Flammarion’s arguments, as did many of his colleagues. Flammarion was consequently fired from the Observatory… I have had better luck so far…
I’m allowed to be fascinated by the possibility that we could find information on how human beings arose and/or discover life forms elsewhere. Mars, Venus, Titan, Enceladus, Europa and other such places have been our favorite targets for exploring habitats in the Solar System and pushing current models of the origin and evolution of life to their limits, and beyond. Subsurface liquid water oceans, organic constituents swimming in exposed hydrocarbon lakes, water-laden geysers, the possibility of water hiding beneath the CO2 ice fields of Mars: All these new opportunities for exploration in the field of Astrobiology make my every day life and research work exciting and busy. Learning about and contributing to future missions to the Saturnian and Jovian systems are constant sources of joy and reward. And I love sharing these new findings in Astronomy with the public, always supportive and sometimes as passionate as we are… [an excerpt of this text was published in the “Pioneers in Astrobiology” section of the Astrobiology Magazine in February 2012]