This liquid water, in combination with a rocky silicate seabed and radiolytic production of surface oxidants, may provide a chemically rich ocean that would be considered habitable. While Europa's surface may hold clues to the composition of an internal ocean, debate still continues over surface chemistry and how exogenous radiation processing and endogenous oceanic emplacement play a role on this moon. One way to understand Europa is to determine whether the external composition reflects the ocean's internal chemistry. Results from the Near Infrared Mapping Spectrograph (NIMS) instrument on Galileo inferred that Europa's surface was dominated by hydrated sulfate salts that likely evaporated from an internal ocean. Finding that these spectral signatures are more predominant in what appear to be younger soils strengthens the hypothesis that these are the recently located evaporates. Further spectral studies, however, showed that these same NIMS surface spectra could be explained just as well by a surface dominated by hydrated sulfuric acid. Sulfuric acid is the likely result of bombardment of an ice surface by sulfur ions. These sulfur ions ultimately come from volcanoes located on Io, and then dissociated, ionized, and accelerated by Jupiter's rapidly rotating magnetic field until they hit Europa. Such radiolysis could also elucidate the sulfur dioxide and sulfur allotropes observed on Europa's surface and their preferred appearance in the more heavily bombarded posterior hemisphere. The existence of sulfuric acid and other sulfur products seems almost inevitable, but the salt hypothesis is still compelling (Brown 1). If there were to be a mission to Europa, it might be......half of paper. .....out.com Chemistry. Np, nd Web. May 2, 2014. Kivelson, Margaret G., Krishan K. Khurana, Christopher T. Russell, Martin Volwerk, Raymond J. Walker, and Christophe Christophe Zimmer. “Galileo Magnetometer Measurements: A Stronger Case for a Subterranean Ocean in Europe.” Science vol. 289 (2000): 1340-1343. Print."Our solar system: Galileo's observations on the Moon, Jupiter, Venus and the Sun." Exploring the Solar System: Science and Technology: Scientific Features: Our Solar System: Galileo's Observations of the Moon, Jupiter, Venus, and the Sun. NASA and Web. April 28, 2014.Showman, Adam P., and Renu Malhotra. "The Galilean satellites". Science 1 October 1999: p77-p84Tyler, Robert H. "Strong oceanic tidal flow and heating on the moons of the outer planets." Nature: Letters 456 (2008): 770-773. Press.