Earth as a tool for astrobiology - A European perspective

Abstract

Scientists use the Earth as a tool for astrobiology by analysing planetary field analogues (i.e. terrestrial samples and field sites that resemble planetary bodies in our Solar System) . In addition, they expose the selected planetary field analogues in simulation chambers to conditions that mimic the ones of planets, moons and Low Earth Orbit (LEO) space conditions , as well as the chemistry occurring in interstellar and cometary ices . This paper reviews the ways the Earth is used by astrobiologists: (i) by conducting planetary field analog ue studies to investigate extant life from extreme environments, its metabo lisms, adaptation strategies and modern biosignatures; (ii) by conducting planetary field analog ue studies to investigate extinct life from the oldest rocks on our planet and its biosignatures; (iii) by exposing terrestrial samples to simulated space or pl anetary environments and producing a sample analog ue to investigate changes in minerals, biosignatures and microorganisms. T he European Space Agency (ESA) created a topical team in 2011 to investigate recent activities using the Earth as a tool for a strobi ology and to formulate recommendations and scientific needs to improve ground - based astrobiological research. Space is an important tool for astrobiology (see Horneck et al., 2016 ; Cottin et al, submitted), but access to space is limited. Complementing res earch on Earth provides fast access, more replications and higher sample throughput. The major conclusions of the topical team and suggestions for the future include more scientifically qualified calls for field campaigns with planetary analogy , and a cent ralized point of contact at ESA or the EU for the organization o f a survey of such expeditions. An improvement of the coordinated logistics, infrastructures and funding system supporting the combination of field work with planetary simulation investigation s , as well as an optimization of the scientific return and data processing, data storage and data distribution is also needed . Finally, a coordinated EU or ESA education and outreach program would improve the participation of the public in the astrobiologi cal activities.