NASA Astrobiology Institute (NAI)

Europa Focus Group

Ronald Greeley, Chair
Department of Geological Science
Arizona State University
Greeley@asu.edu

The objective of the Europa Focus Group (EFG) is to foster scientific studies and joint investigations of Europa and related research in order to understand the exobiological potential of this satellite of Jupiter. This goal is to be met through various video conferences, workshops, and information exchanges sponsored by the NAI. The study of Europa requires a multidisciplinary approach using spacecraft data analyses, laboratory simulations, terrestrial analog studies, and other techniques to understand the complex history and present environments on and in Europa. Participation in the EFG is, therefore, open to all interested members of the relevant communities, including (but not restricted to) planetary scientists, biologists, and terrestrial ice scientists.

Background

Europa has been identified by NASA (1999) and the National Academy of Sciences (NRC, 1999; 2000) as a high priority for exploration. This priority is established largely because Europa appears to be one of the few objects in our Solar System having conditions favorable for life. Europa is a rocky object slightly smaller than Earth ‘s moon. It has an outer shell of water composition, modeled to be ~150 km thick, the surface of which is frozen. Several lines of evidence suggest that liquid water existed below the ice crust in the recent geologic past, and that liquid water might be present today. Friction generated by tides within Europa through its interaction with Jupiter and neighboring satellites might generate sufficient heat to fuel silicate volcanism at the base of the water layer. These factors, coupled with remote sensing observations of various salts on the surface and the likely implantation of organic compounds through cometary impact lead to the presence of the essential ingredients for exobiology: an energy source, water (possibly liquid), and organic chemistry. The Europa Focus Group provides a forum to bring the relevant interests together to exchange information and share ideas regarding Europa, including plans for its future exploration.

References Cited

NASA (1999)AO 99-OSS-04, Deep Space Systems -Europa Orbiter Mission. National Research Council (1999)A Science Strategy for the Exploration of Europa. National Academy Press, Washington, D. C. , 68 p. National Research Council (2000)Preventing the Forward Contamination of Europa. National Academy Press, Washington, D. C. , 54 p.