[Wednesday, January 2, 2008] Europa is a prime target for astrobiology. The presence of a global subsurface liquid water ocean and a composition likely to contain a suite of biogenic elements make it a compelling world in the search for a second origin of life.

[Wednesday, January 2, 2008] We examine means for driving hydrothermal activity in extraterrestrial oceans on planets and satellites of less than one Earth mass, with implications for sustaining a low level of biological activity over geological timescales.

[Wednesday, January 2, 2008] Radiolysis of water may provide a continuous flux of an electron donor (molecular hydrogen) to subsurface microbial communities.