Article,
Interior structure models and tidal Love numbers of Titan
Journal of Geophysical Research-Planets, 108 (E12): 5130 (2003)
Abstract
Interior models of a differentiated Titan with an internal ammonia-water
ocean and chondritic radiogenic heat production in an undifferentiated
rock + iron core have been calculated. We assume thermal and mechanical
equilibrium and calculate the structure of the interior as a function
of the thickness of an ice I layer on top of the ocean as well as
the moment of inertia factor and the tidal Love numbers for comparison
with Cassini gravity data. The Love numbers are linearly dependent
on the thickness of the ice I shell at constant rheology parameters
but decrease by one order of magnitude in the absence of an internal
ocean. Ice shell thicknesses are between 90 and 105 km for models
with 5 wt.% ammonia and for core densities between 3500 and 4500
kg m(-3). For 15 wt.% ammonia, the shell is 65 to 70 km thick. We
use a strongly temperature-dependent viscosity parameterization of
convective heat transport and find that the stagnant lid comprises
most of the ice I shell. Tidal heating in the warm convective sublayer
is of minor importance. The internal ocean is several hundred kilometers
thick, and its thickness decreases with increasing thickness of the
ice shell. Core sizes vary from 1500 to 1800 km radius with associated
moment of inertia factors of 0.30+/-0.01.
Tags
- ammonia-water
- dependent
- europa
- evolution;
- galilean
- gravity-field;
- heat-flow;
- icy
- internal
- large
- oceans;
- satellites;
- structure;
- subsurface
- surface
- system;
- thermal
- viscosity;
