HR: 10:20h
AN: B51G-01 INVITED     [PDF]
TI: Astrobiology as an Integrating Theme in Solar System Exploration
AU: * Jakosky, B M
EM: bruce.jakosky@lasp.colorado.edu
AF: University of Colorado, LASP/Campus Box 392, Boulder, CO 80309-0392 United States
AB: The discipline of astrobiology examines (i) the origin and evolution of life on Earth and the detailed interplay between biological and planetary evolution, (ii) the evolution of our solar system and the potential and actual distribution of life within it, (iii) the occurrence of planets around other stars and their potential for life, and (iv) the interplay between each of these areas. In our own solar system, astrobiology encompasses much more than just the search for life on Mars or Europa. Our goal is to understand the nature of planetary habitability--which planets have evolved to have environments that are habitable by microorganisms, and which have not. By understanding the processes that control the architecture of our solar system, we can extrapolate how these same processes might have played out in other planetary systems and what the distribution of habitability might be beyond our own system. In this context, Mars and Europa appear as potentially habitable worlds either today or in the past, Ganymede and Callisto might have deep subsurface oceans and be habitable, Venus might have been habitable early on but does not appear to be today, and Titan probably has had intermittent liquid water as well as ongoing chemical evolution involving organic molecules. Looking more broadly, the origin and the evolution of the gas-giant planets and their dynamical effects have had a major influence on the terrestrial planets; the characteristics of the Kuiper belt and Oort cloud influence our understanding of early chemical and volatile processes that affect habitability; and asteroids have had a tremendous impact on the terrestrial planets throughout their history. In order to understand planetary habitability in general, and the implications of a discovery of the presence or absence of life on any given object, we need to understand the detailed origin and evolution of our solar system as a whole and of the individual bodies within it. A broad program of planetary exploration is the best way to investigate the astrobiology of our solar system.
DE: 6207 Comparative planetology
SC: Biogeosciences [B]
MN: 2003 Fall Meeting