International Journal of Astrobiology

Research Article

Amino acid synthesis in Europa's subsurface environment

Sam H. Abbasa1 and Dirk Schulze-Makucha2

a1 Chemistry Department, Palomar Community College, San Marcos, CA 92069, USA e-mail: sabbas@palomar.edu

a2 School of Earth & Environmental Sciences, Washington State University, Pullman, WA 99164, USA

Abstract

It has been suggested that Europa's subsurface environment may provide a haven for prebiotic evolution and the development of exotic biotic systems. The detection of hydrogen peroxide, sulfuric acid, water, hydrates and related species on the surface, coupled with observed mobility of icebergs, suggests the presence of a substantial subsurface liquid reservoir that actively exchanges materials with the surface environment. The atmospheric, surface and subsurface environments are described with their known chemistry. Three synthetic schemes using hydrogen peroxide, sulfuric acid and hydrocyanic acid leading to the production of larger biologically important molecules such as amino acids are described. Metabolic pathways based on properties of the subsurface ocean environment are detailed. Tidal heating, osmotic gradients, chemical cycling, as well as hydrothermal vents, provide energy and materials that may support a course of prebiotic evolution leading to the development or sustenance of simple biotic systems. Putative organisms may employ metabolic pathways based on chemical oxidation–reduction cycles occurring in the putative subsurface ocean environment.

(Received February 08 2008)

(Accepted May 08 2008)