Astrobiology: Approaches to the Origin of Life on Earth and Beyond

Abstract

The present concepts devoted to definition, origin, and distribution of life in the Universe are reviewed. The “Earth Cradle” (origin of life) and “Panspermia” (distribution of life) directions of research are integrated in the interdisciplinary astrobiology science. The author’s approach to answer key questions of astrobiology—“What is life?” and “How does life begin?”—is formulated. It implies consideration of the origin-of-life process in the succession from thermodynamics to prebiotic chemistry and biochemistry. Based on the approach, the inversion concept is substantiated. It characterizes the unique biological method of organization and proposes the way to primary living system formation. A key thesis of the concept is the transition of prebiotic microsystems into initial forms of life through thermodynamic inversion , when contributions of free energy and information start prevailing over-contribution of entropy. A lot of data on terrestrial life, prebiotic chemistry, and natural environments are used to detail this process. Exploration of hydrothermal systems in Kamchatka Peninsula allowed considering them as models of prebiotic environments.