The recently measured dimensionless moment of inertia (Mol) factor
for Callisto of 0.3549 +/- 0.0042 (Anderson et al., 2001, Icarus,
153, 157-161) poses a problem: its value cannot be explained by a
model in which Callisto is completely differentiated into an ice
shell above a rock shell and an iron core such as its neighboring
satellite Ganymede nor can it be explained by a model of a homogeneous,
undifferentiated ice-rock satellite. We show that Callisto may be
incompletely differentiated into an outer ice-rock shell in which
the volumetric rock concentration is close to the primordial one
at the surface and decreases approximately linearly with depth, an
ice mantle mostly depleted of rock, and an about 1800 km rock-ice
core in which the rock concentration is close to the close-packing
limit. The ice-rock shell thickness depends on uncertain rheology
parameters and the heat flow and can be roughly 50 to 150 km thick.
We show that if Callisto accreted from a mix of metal bearing rock
and ice and if the average size of the rocks was of the order of
meters to tens of meters, then Callisto may have experienced a gradual,
but still incomplete unmixing of the two components. An ocean in
Callisto at a depth of 100-200 km is difficult to obtain if the ice
is pure H2O and if the ice-rock lithosphere is 100 km or more thick;
a water ocean is more plausible for ice contaminated by ammonia,
methane or salts; or for pure H2O at a depth of 400-600 km. (C) 2004
Elsevier Inc. All rights reserved.
%0 Journal Article
%1 Nagel2004
%A Nagel, K.
%A Breuer, D.
%A Spohn, T.
%D 2004
%J Icarus
%K imported
%N 2
%P 402--412
%T A model for the interior structure, evolution, and differentiation of Callisto
%V 169
%X The recently measured dimensionless moment of inertia (Mol) factor
for Callisto of 0.3549 +/- 0.0042 (Anderson et al., 2001, Icarus,
153, 157-161) poses a problem: its value cannot be explained by a
model in which Callisto is completely differentiated into an ice
shell above a rock shell and an iron core such as its neighboring
satellite Ganymede nor can it be explained by a model of a homogeneous,
undifferentiated ice-rock satellite. We show that Callisto may be
incompletely differentiated into an outer ice-rock shell in which
the volumetric rock concentration is close to the primordial one
at the surface and decreases approximately linearly with depth, an
ice mantle mostly depleted of rock, and an about 1800 km rock-ice
core in which the rock concentration is close to the close-packing
limit. The ice-rock shell thickness depends on uncertain rheology
parameters and the heat flow and can be roughly 50 to 150 km thick.
We show that if Callisto accreted from a mix of metal bearing rock
and ice and if the average size of the rocks was of the order of
meters to tens of meters, then Callisto may have experienced a gradual,
but still incomplete unmixing of the two components. An ocean in
Callisto at a depth of 100-200 km is difficult to obtain if the ice
is pure H2O and if the ice-rock lithosphere is 100 km or more thick;
a water ocean is more plausible for ice contaminated by ammonia,
methane or salts; or for pure H2O at a depth of 400-600 km. (C) 2004
Elsevier Inc. All rights reserved.
@article{Nagel2004,
abstract = {The recently measured dimensionless moment of inertia (Mol) factor
for Callisto of 0.3549 +/- 0.0042 (Anderson et al., 2001, Icarus,
153, 157-161) poses a problem: its value cannot be explained by a
model in which Callisto is completely differentiated into an ice
shell above a rock shell and an iron core such as its neighboring
satellite Ganymede nor can it be explained by a model of a homogeneous,
undifferentiated ice-rock satellite. We show that Callisto may be
incompletely differentiated into an outer ice-rock shell in which
the volumetric rock concentration is close to the primordial one
at the surface and decreases approximately linearly with depth, an
ice mantle mostly depleted of rock, and an about 1800 km rock-ice
core in which the rock concentration is close to the close-packing
limit. The ice-rock shell thickness depends on uncertain rheology
parameters and the heat flow and can be roughly 50 to 150 km thick.
We show that if Callisto accreted from a mix of metal bearing rock
and ice and if the average size of the rocks was of the order of
meters to tens of meters, then Callisto may have experienced a gradual,
but still incomplete unmixing of the two components. An ocean in
Callisto at a depth of 100-200 km is difficult to obtain if the ice
is pure H2O and if the ice-rock lithosphere is 100 km or more thick;
a water ocean is more plausible for ice contaminated by ammonia,
methane or salts; or for pure H2O at a depth of 400-600 km. (C) 2004
Elsevier Inc. All rights reserved.},
added-at = {2009-11-03T20:21:25.000+0100},
author = {Nagel, K. and Breuer, D. and Spohn, T.},
biburl = {https://www.bibsonomy.org/bibtex/2bebbdc19992f514308e6e2697eeae700/svance},
interhash = {f4a8b57247ca5e53d9af27edebec862d},
intrahash = {bebbdc19992f514308e6e2697eeae700},
journal = {Icarus},
keywords = {imported},
number = 2,
owner = {svance},
pages = {402--412},
timestamp = {2009-11-03T20:22:07.000+0100},
title = {A model for the interior structure, evolution, and differentiation of Callisto},
volume = 169,
year = 2004
}