Habitat-OASIS addresses the question of habitability of the outer solar system by looking at spacecraft data and preparing for future space missions using novel approaches. The classical view held that for a planet or moon to be habitable requires liquid water at or near its surface. This view has been challenged by the discovery of numerous subsurface oceans below the icy crusts of moons orbiting Jupiter and Saturn. The amount of water detected there is several times higher than on Earth and it is kept liquid primarily by tidal heating rather than solar heating. In particular, the cryo-volcanic moons Enceladus and Europa, orbiting Saturn and Jupiter respectively, are considered to have the largest astrobiological potential. On these two moons, the ocean floor is in contact with a rocky core and there are indications for hydrothermal activity - hot water flowing out from the rocky sea floor into the ocean. On Earth, these kinds of hydrothermal vents are places where life developed independently of sunlight.
On Enceladus (and probably also on Europa), active plumes expel ice grains carrying matter previously dissolved and suspended in the subsurface oceans, allowing their geochemistry to be investigated and constrained. The mass spectrometers aboard the Cassini-Huygens spacecraft, in orbit around Saturn until September 2017, analyzed this material and have already delivered spectacular science results. Project 1 of this proposal is a refined data analysis of the Enceladus plume material using novel techniques and is the first ever opportunity to explore in detail a potential ocean habitat outside Earth. Newly developed laser-assisted dispersion experiments are used to acquire mass spectra of a wide variety of analogue materials, enabling the identification and quantification of inorganic, organic and possibly biogenic compounds embedded in the ice grains. Geochemical aqueous alteration experiments and numerical modelling help to further constrain the habitability of Enceladus and extrapolate the results to other ocean moons. Project 2 will leverage the laboratory capabilities from Project 1 to create a comprehensive library of mass spectra in preparation for the upcoming missions visiting Jupiter’s icy moons: ESA’s JUICE Mission and NASA’s Europa Clipper Mission. Having analogue measurements available early in the missions will be critical for exploiting their full potential.
The different aspects of Habitat-OASIS:
• Laboratory for Planetologie and Geodynamik (LPG), Univ. of Nantes
• Laboratory for Atmospheric and Space Physics (LASP), Univ. of Colorado, Boulder
• Jet Propulsion Laboratory (JPL), Caltech, Pasadena
• Institut für Raumfahrtsysteme (IRS), Univ. of Stuttgart
• Leibniz Institut für Oberflächensysteme (IOM) Leipzig
• Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPCE), Univ. of Orleans
• Open University Astrobiology Research Group, The Open Univ., Milton Keynes
• Astronomy Research Unit, University of Oulu (Finland)