Signatures of Life on Earth and in Cosmos - ASG, Pufendorf IAS

Advanced study Group (ASG) at the Pufendorf Institute for Advanced Studies

An important aspect of astrobiology is the ability to clearly distinguish signs of past or present life in extraterrestrial environments. A better understanding of how to distinguish signs of life from alternative inorganic processes has the potential to enrich the general understanding of how planetary systems evolve over geological and astronomical time-scales. For example, what does the presence of water and minerals such as hematite on the surface of Mars tell us in terms of its geological history, and what can the spectroscopic detection of gases such as carbon dioxide, methane, and oxygen in the atmosphere of an exoplanet indicate about its propensity to harbour life?

We do not at this point know enough about the biomarker signals for different species on the earth. Data both for extinct fossil forms and for now-living organisms are largely lacking. How can we interpret data from the Mars
rovers when we do not have a full picture of the data we have from our own earth?

Signs of life can be in the form of chemical signatures, biogeology, or electromagnetic waves. To correctly interpret the signs it is necessary to have a deep understanding of the chemical, physical, geological, biological, and semiotic aspects involved. Of equal importance is a deep understanding of the linguistic, cognitive, and cultural aspects involved in producing and interpreting signs, and a conceptual understanding of ‘life’ as a phenomenon. In order to put these aspects into perspective, an understanding of the historical, philosophical, social, and cultural aspects is also important. In other words, to find, identify, and interpret signatures of life, an interdisciplinary approach is essential.