2013 Annual Science Report
Astrobiology Roadmap Objective 3.3 Reports Reporting | SEP 2012 – AUG 2013
Our multidisciplinary team from USC, Caltech, JPL, DRI, and RPI is developing and employing field, laboratory, and modeling approaches aimed at detecting and characterizing microbial life in the subsurface—the intraterrestrials. We posit that if life exists, or ever existed, on Mars or other planetary body in our solar system, evidence thereof would most likely be found in the subsurface. This study takes advantage of unique opportunities to explore the subsurface ecosystems on Earth through boreholes, mine shafts, and deeply-sourced springs. Access to the subsurface, both continental and marine, and broad characterization of the rocks, fluids, and microbial inhabitants is central to this study. Our focused research themes require subsurface samples for laboratory and in situ experiments. Specifically, we seek to carry out in situ life detection and characterization experiments, employ numerous novel and traditional techniques to culture heretofore unknown intraterrestrial archaea and bacteria, and incorporate new and existing data into regional and global metabolic energy models.ROADMAP OBJECTIVES: 2.1 2.2 3.1 3.3 4.1 5.1 5.2 5.3 6.1 6.2 7.2
What can we learn about pre-biotic chemistry by studying Titan? The surface of Titan is a special place for the study of pre-biotic chemistry because that is where the organic haze sedimenting from the atmosphere can come in contact with liquid water (briefly, from cryovolcanic eruptions) to form amino acids and other molecules relevant to life. But an energy source is also needed, and this may come from short-wave (ultraviolet – blue) solar radiation that makes its way through Titan’s dense haze layer to the surface. In this study we calculated the amount of UV-blue solar flux at Titan’s surface based on measurements made by the Descent Imager/Spectral Radiometer (DISR) instrument on the Huygens Probe coupled with radiative transfer models that include haze optical properties.ROADMAP OBJECTIVES: 2.2 3.1 3.2 3.3
Although thermodynamics dictates that all spontaneous processes must be purely dissipative and “destructive” (the notoriously ungenerous face of the “2nd law”), under particular circumstances a spontaneous process can be a compound of two mechanistically coupled sub-processes only one of which (necessarily the larger one), is dissipative while its coupled, lesser partner is literally “driven” to be creative and generative – that is, a process that can “do work”, “build stuff”, and “make things happen”. A system functioning in this way is technically an engine and all living systems are necessarily, examples of such thermodynamically compound and creative “engine” systems – while at the same time operating internally via a complex, interlinked clockwork of such engines.
Moreover, living systems inherently belong to a special thermodynamic subclass of such engines, namely those that are “autocatalytic” (self-growing and self-stabilizing) in their operation. Arguably, in fact, it is the property of being autocatalytic thermodynamic engines which at root underlies the potency and magic of living systems and which at the same time constitutes life’s most assuredly universal, fundamental, and primitive property. However, as of yet, we understand the implications of these thermodynamic facts quite poorly – notwithstanding that they seem certain to materially impact questions regarding the origin of life, evolutionary dynamics, and community, trophic, and ecology-level organization.
The present project undertakes to redress this situation to some extent by investigating the formal dynamical behavior of model systems made up of interacting, thermodynamically driven, autocatalytic engines.ROADMAP OBJECTIVES: 3.3 3.4 4.2 5.1 5.2
Task 3.2: Longer Wavelength Photochemistry of Condensates and Aerosols in Titan’s Lower Atmosphere and on the Surface.
This study focuses on the condensed phase photochemistry on Titan. In particular, we focus on understanding longer wavelength photochemistry of solid hydrocarbons to simulate photochemistry that could occur based on the UV penetration through the atmosphere and on the evolution of complex organic species in astrobiologically significant regions on Titan’s surface. Here we investigate the oxygenation chemistry involving the condensed Titan’s organic aerosols with water-ice on Titan’s surface – induced by high energy photons simulating the cosmic ray induced chemistry on Titan’s surface.ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3