HR: 10:20h
AN: SA12A-01 INVITED     [Abstracts]
TI: Using Magnetic Induction to Explore Liquid Water in icy Satellites
AU: * Khurana, K K
EM: kkhurana@igpp.ucla.edu
AF: Institute of Geophysics and Planetary Physics, University of California at Los Angeles, Los Angeles, CA 90095 United States
AB: Magnetic field observations made by Galileo in the vicinity of Europa, Ganymede and Callisto showed that strong magnetic induction fields emanate from these moons in response to the rotating magnetic field of Jupiter. Further analyses have shown that the magnetic induction fields are consistent with the presence of subsurface liquid oceans in these moons. Many independent lines of geological and geophysical evidences support this conclusion for Europa and Ganymede. For example, the very young age (< 20 my) of Europa's surface and the isostatic relaxation of recent impact craters suggest that Europa's surface is renewed by processes operating in a low viscosity region beneath the surface. Similarly, the formation of pull-apart bands on Europa and Ganymede are facilitated by the presence of a liquid or a very low viscosity material beneath a thin crust. The induction signature from Callisto, however, is a complete surprise. We will discuss the present status and future plans of magnetic induction studies devoted to exploring liquid water in the icy Galilean satellites. Next, we will discuss how one could use the magnetic induction to explore the interiors of icy satellites in other solar system bodies such as Titan and other icy moons of Saturn. We will discuss how the uncertainty in the determination of the thickness of the ocean could be minimized by making magnetic induction measurements at multiple frequencies. Finally, we discuss how the orbital measurements of the magnetic field could be combined with observations made on the surfaces of the icy moons to yield a more robust data set which can be inverted uniquely for ocean conductivity and thickness.
DE: 5407 Atmospheres--evolution
DE: 2732 Magnetosphere interactions with satellites and rings
DE: 2780 Solar wind interactions with unmagnetized bodies
DE: 2784 Solar wind/magnetosphere interactions
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting