To place astrobiological investigations in context, we must understand the transition of prebiotic to biotic and how this influences planetary exploration. Titan is an excellent example of a prebiotic world, where photochemistry in the atmosphere leads to a plethora of organics on the surface. The liquid hydrocarbon lakes of Titan, composed primarily of methane and ethane, are a unique environment where dissolution and precipitation of species may lead to active processes on the surface. We have discovered that benzene forms an inclusion compound with ethane in Titan-like conditions, and may be the first example of surface processes capable of selectively sequestering and storing ethane in Titan surface materials.
In parallel, an international collaboration inspired by the 2012 NASA Nordic Astrobiology Summer School, successfully completed a field expedition to Iceland to test life detection techniques and decision-making strategies in a Mars-like analogue environment. We discovered that habitability and microbial diversity may vary widely, even in areas that appear to be geologically homogeneous. This has implications for field sampling and analysis of volcanic regions on Mars. Sampling strategies should target as many spatially separated sites as practical to improve the chances of detecting life.