Description du projet
À la recherche d’eau liquide souterraine dans les lunes du système solaire
La présence d’eau liquide est l’une des rares conditions préalables essentielles à la vie, du moins telle que nous la connaissons sur Terre. De vastes étendues d’eau peuvent se cacher sous la croûte glacée de certaines lunes de notre système solaire. Combinant des simulations informatiques et de nouvelles observations au télescope, le projet Exo-Oceans, financé par l’UE, prévoit de rechercher des océans sur les lunes de Saturne (Titan et Encelade) mais également en dehors de notre système solaire. Les travaux de recherche permettront de procéder à des analyses détaillées des océans observés sur les lunes de Jupiter (Europa et Ganymède). Bien que la présence d’eau sur les deux lunes ait déjà été établie, les approches précédentes n’ont pas permis de caractériser ces océans cachés. Les résultats du projet serviront de base fondamentale pour l’étude des océans et de la vie extraterrestre.
Objectif
The existence of liquid water is one of the few preconditions for life as we know it. Therefore, the search and characterization of liquid water outside of Earth plays an essential role in the search for extraterrestrial life. Prominent candidates to host liquid water are moons in the outer solar system, which can maintain oceans under their icy surfaces. The currently most effective way to identify such subsurface oceans is through effects of their salinity and thus electrical conductivity. The conductivity modifies the magnetic field around these moons through a process referred to as electromagnetic induction. Spacecraft measurements of associated magnetic field perturbations provided evidence for oceans within Jupiter’s moon Europa and Ganymede. Current analysis tools however reached an impasse. No scientific techniques are available, which provide quantitative estimates and uncertainties of key ocean properties when the effects of the dense magnetized plasmas around the moons are included. Here we propose entirely new approaches, which overcome these issues. Our novel techniques will include a simultaneous treatment of the physics in all internal and external conductive layers and will for the first time use all available observations including auroral emission to go beyond considering magnetic fields only. EXO-OCEANS will systematically characterize the ocean properties on Europa and Ganymede including the ocean candidate Callisto. Characterizing the oceans on Ganymede, Europa and Callisto are at the heart of ESA’s Juice and NASA’s Europa Clipper missions. For Saturn’s moons Titan and Enceladus where currently existing techniques do not work, we will invent a new detection technique. In parallel we will use the Hubble Space Telescope to search and characterize aurora in extrasolar planetary systems to pave the way for ocean detections beyond the solar system.
Champ scientifique
- engineering and technologymechanical engineeringvehicle engineeringaerospace engineeringastronautical engineeringspacecraft
- natural sciencesphysical sciencesastronomyobservational astronomyoptical astronomy
- natural sciencesphysical scienceselectromagnetism and electronics
- natural sciencesphysical sciencesastronomyplanetary sciencesnatural satellites
Mots‑clés
Programme(s)
Thème(s)
Régime de financement
ERC-ADG - Advanced GrantInstitution d’accueil
50931 Koln
Allemagne