Section headings and selected papers: Structure and Organic Chemistry in Comets . Cometary origin of carbon and water on the terrestrial planets, A H Delsemme. The cometary contribution to prebiotic chemistry. J Oro et al . Radiolysis of aqueous formaldehyde relevant to cometary environments, S Castillo-Rojas et al . Radiation-induced syntheses in cometary simulated models, A Negron-Mendoza et al . Cometary/meteor coupling: structure of young streams, N V Kulikova. Impact of Human Expeditions to Mars . Science strategy for human exploration of Mars, C R Stoker et al . Stable carbon isotopes: possible clues to early life on Mars, M Schidlowski. The use of mineral crystals as bio-markers in the search for life on Mars, D E Schwartz et al . Chemical, Physical and Astronomical Perspectives on Life in the Universe . The initiation of biological processes on Earth: summary of empirical evidence, M Schidlowski. The search for extra-solar planetary systems, F Paresce. Evolution of Primitive Biochemical Functions . Polycyclic aromatic hydrocarbons: primitive pigment systems in the prebiotic environment, D W Deamer. Some aspects of the early evolution of photosynthesis, Z Masinovsky et al . Life in Extreme Environments . Survival in extreme dryness and DNA-single strand breaks, K Dose et al . Anhydrobiosis: a strategy for survival, L M Crowe & J H Crowe; Long-term preservation of microbial ecosystems in permafrost, D A Gilichinsky et al . Survival rates of some terrestrial microorganisms under simulated space conditions, J Koike et al . Cometary habitats for primitive life, M K Wallis et al . Author Index.
