Lifetime of Organic Molecules at the Surface of Europa

Introduction: The possible existence of an ocean beneath the surface of Jupiter’s icy moon Europa has fueled scientific interest in this tiny world. Liquid water is a crucial element in the development of life on Earth, and if present on Europa, increases the likelihood of finding life there as well. Hydrothermal vents on the Europan ocean floor could provide habitat for microbes as well as generate significant quantities of organic molecules, as they do on Earth. In a recent publication, Johnson et al. [1] estimated the density of organic molecules sputtered from the surface of Europa, and implied that their detection could verify the existence of organics in a sub-surface ocean. In the context of developing spacecraft missions, it is therefore important to understand the nature of organic molecules on Europa’s surface.