skip to main content
Caltech
Division of Geological and Planetary Sciences

David J. (Dave) Stevenson

Home  /  People  /  David J. (Dave) Stevenson

David J. (Dave) Stevenson

Marvin L. Goldberger Professor of Planetary Science, Emeritus
B.S., Victoria University (New Zealand), 1971; M.S., 1972; Ph.D., Cornell University, 1976; D.S.c., Victoria University. Associate Professor, Caltech, 1980-84; Professor, 1984-95; Van Osdol Professor, 1995-2011; Goldberger Professor, 2011-21; Goldberger Professor, Emeritus, 2021-; Division Chair, 1989-94.
Research Summary
Internal structure and evolution of both major and terrestrial planets; application of fluid dynamics and magnetohydrodynamics to planetary interiors; origin of the solar system.

Research Options

Geophysics;  Planetary Science; 

Profile

1. Earth and Moon Formation

In our current understanding of the formation of the terrestrial planets, giant impacts play a central role and the formation of the Moon is a late stage consequence of a particularly large oblique impact. Following such a large impact, a molten silicate disk forms in Earth orbit, evolving quickly to form the Moon, perhaps on a timescale of 100 to 1000 years (Thompson and Stevenson, 1988) or perhaps even faster (Machida and Abe, 2004). This part of the evolution is not well understood (it cannot be modeled by planetesimal evolution). During this phase, the disk has a massive silicate vapor atmosphere that is continuously joined to the silicate atmosphere of the post-giant impact Earth. The goal of this work is to explain the geochemical characteristics of the Moon as the result of processes occurring immediately after the giant impact. This model has the potential to explain both the Earth-Moon similarities and differences.

Figure 1

Figure 1. Standard oxygen isotope plot showing the remarkable similarity of Earth & Moon compared to Mars Figure

figure 2


2. Cross-sectional view of the silicate melt & vapor disk within which mixing may take place between earth and Moon-forming material during a time ~100yrs after disk formation.

Contrary to the corresponding solar nebula problem (which is quasi-steady state) this rapidly evolving system is expected to have vigorous turbulent convection and therefore turbulent mixing far greater than that commonly attributed to the planet-forming disk. As a result, we believe this model offers the prospect of explaining the Earth-Moon similarity in oxygen isotopes shown in Fig 1. In our scenario, the incoming giant impactor has a different oxygen isotopic character, as one would expect based on current accretion models (Chambers, 2001). However, convective mixing through the common massive silicate atmosphere dilutes the moon-forming isotopic distinctiveness and reduces (though perhaps not completely eliminates) the isotopic difference. Because we do not have a full understanding of the relevant dynamics, our approach is to emphasize observational tests. However, simple estimates of turbulent mixing suggest that it is possible to explain the Earth-Moon similarity by this model.

To the extent that this model is successful in explaining the difference in composition between the Moon and silicate Earth, it may be possible to place constraints on the T, P of last equilibration with the Moon. The goal here is to quantify this effect using equilibrium thermodynamics and use this prediction as a test of the mixing model. We also look at the behavior of water and of other isotopic systems.

In a related effort, we have been studying the fluid dynamic of mixing between the cores of massive projectiles and the partially molten mantle of Earth, immediately after a giant impact. This is relevant to the question of how to best interpret Hf-W isotopic data that are used to explain the timing of earth formation and core formation. We find that there is incomplete re-equilibration of core and mantle during and immediately after a giant impact (i.e., some of the iron finds it way to the core without the opportunity to pick up the siderophilic tungsten made by hafnium decay in Earth's mantle during the millions of years prior to the giant impact.) This suggests problems for the connection between Hf-W chronologies and the precise timing of events during Earth and Moon formation. See also Stevenson (1990).

2. Giant Planet Zonal Flows

The giant planets exhibit strong east-west winds in the observable atmosphere. It has been argued, most notably by Busse (1983), that this flow is deep-seated, i.e., it extends down into the interior on cylinders, as shown in this figure for Jupiter.

Figure 3

Figure 3. The relationship between atmospheric and interior flows proposed by Busse. Our work suggests that this picture must be incorrect.

However, these cylinders may reach to levels where the electrical conductivity is sufficient to allow coupling of the flow to the magnetic field. Even a magnetic Reynolds number somewhat less than unity can correspond to a significant current generation. Our result for Jupiter is that a deep-seated zonal flow is in fact highly unlikely and certainly very restricted in radial extent. The main difficulty is that such a flow will create large electrical currents in a low conductivity region. The associated Ohmic dissipation then exceeds the luminosity of Jupiter. The zonal flow must be confined to the outermost 4% of the planetary radius in Jupiter (and a somewhat thicker layer in the other giant planets). This is the rigorous part of the analysis. But in addition, the hypothesized flow has no force acting on it seems capable of providing the shear needed to reduce its amplitude from ~100m/s to a tolerable fraction of a meter per second if this shear exists in the high density region where the conductivity begins to be important. In particular, Lorentz forces are grossly insufficient.

It seems likely that the flow seen in the atmosphere of Jupiter is mostly "meteorological" (i.e., it is a shallow layer flow). These results are testable because deep seated flows yield gravitational signals that are detectable by the JUNO spacecraft, scheduled for launch in 2011.

3. Planetary Magnetic Fields

Work continues on the puzzle of how to explain the pattern of magnetic fields in the solar system. Why do some planets have large magnetic fields now or only had them in the distant past? Why does Ganymede have a dynamo while Mars and Titan do not? Although the answers to these puzzles may depend in part on a better understanding of dynamo theory, many of these issues require an understanding of whether these bodies have liquid, convective cores. The main issue here is energy sources (cooling, presence of an inner core, etc.) Here is a recent review on this problem, published as Stevenson(2003b).

It is possible (though far from certain) that these models might also shed light on the puzzling question presented by the new "observation" of Saturn's spin (Giampieri, 2006; Stevenson, 2006). For example, there may be choices of the forcing (i.e., of the zonal flow) for which a high latitude non-dipole field "anomaly" naturally emerges. This would not directly explain the observations but might provide a magnetic anomaly that guides the magnetospheric or ionospheric anomaly responsible for the observed field disturbance. Here is a recently published discussion of Saturn's spin, published as Stevenson(2006).

4. Giant Planet Structure

In the case of Earth and Mars, it has been possible to obtain very accurate moments of inertia from measurements of precession. This technique can be used in principle for the giant planets but it is difficult. For decades, the standard approach to defining the internal structure of the giant planets has instead relied on the interpretation of the gravitational moments. In principle, these contain even more information than the moment of inertia (because we can measure J2, J4 and even J6). However, the interpretation in terms of density structure and the presence or absence of a core is non-unique. The classic Radau-Darwin theory gives the following "recipe":

C/MR2 = 2{1-2/5[5/(Λ2+1) -1]1/2}/3


where C is the polar moment of inertia, M and R are the planet mass and radius respectively, and Λ2 =J2/q where q=Ω2R3/GM, the ratio of centrifugal force to gravity at the equator. More by accident than by good theory, this equation predicts C/MR2 ~0.25 for Jupiter, close to the value that is obtained by detailed models designed to fit the gravitational moments. A coreless n=1 polytrope yields C/MR2 = 0.26. By contrast, a new dynamical model (Ward and Canup, 2006) proposes that Jupiter's obliquity is primarily forced rather than free (i.e., not primordial) and there is empirical evidence in the current pole location compatible with this interpretation. For their theory, C/MR2 =0.236, lower than most interior models, and potentially supportive of a core for Jupiter. The presence or absence of a core is central to our understanding of how the giant planets formed (e.g., Lissauer and Stevenson, 2006).

Aside from being an approximate theory, the Radau-Darwin equation is conceptually incorrect. It implies that there is a one-to-one correspondence between a particular value of Λ2 (an easily measured quantity) and the value of C/MR2. One way to appreciate this conceptual error is to look at the predicted C/MR2 at constant Λ2, for a parameterized set of models. This is shown in Fig 4.

Figure 4

Figure 4 C/MR2 as a function of fractional core radius x at fixed J2/q=0.145 for the exactly solvable model of a core of density A and radius x, overlain by an envelope of density 1 between radius x and radius 1. Models to the left correspond to cores of extremely high density (but finite envelope density); models to the right end point correspond to models where the density of the envelope is going to zero. Models beyond x~0.78 are unphysical (they require negative core densities). These models are not physically relevant to realistic giant planet structures but they demonstrate nicely the non-uniqueness of the relationship between moment of inertia and J2/q. The total range of non-uniqueness is about 15%. This is large!


In our current work we are seeking to understand better the non-uniqueness of the relationship between gravitational moments and moment of inertia or density structure. As a related issue, we are also seeking to understand what the gravitational moments tell us about the coefficient k in the formula Egrav = -kGM2/R. This is important for understand the accretion process, especially for Uranus and Neptune.

Here is a recent review on Jupiter's interior.

5. Icy Satellites

Recent results from Cassini (both in orbit and from Huygens probe) have motivated consideration of models for Titan that involve some form of volcanism. One viewpoint is that there has been geologically recent release of methane from the interior ("recent" could mean as much as a billion years ago). These models are motivated in part by the notion that because methane is continuously destroyed and because there are no oceans and only limited evidence for lakes of methane on the surface, suggesting we must have a deep-seated source. The alternative approach proposes that the methane is in fact primordial (or at least billions of years old) and stored in a regolith near surface (Stevenson, 1992). In such a model there is no difficulty explaining the total needed reservoir of methane and no requirement that this methane be readily observed as oceans or lakes. A model of this kind would necessarily give a "wet" surface because the timescale for transport between surface/atmosphere and subsurface is geologically short. (There can be a methane cycle just as Earth has a near –surface water cycle.) A model of this kind also raises the question of whether the claimed evidence for volcanic constructs on Titan is, in fact, compelling. It is far from clear how to get water–ammonia volcanism on a body like this, although tidal heating may certainly help, since there is a tendency for bodies without recycling to "run down" (i.e., once you have sweated out the water/ammonia, you no longer have the possibility to have more volcanism). There is of course still the opportunity for some intrusive activity including escape of argon-40, without the need to build volcanic structures.

In a related effort, we have also looked recently at the likely non-Newtonian aspect of the water ice rheology resulting from the fact that the so-called Newtonian viscosity is grain-size dependent and the grain size in turn depends on stress. We find that this enlarges the size range for which bodies are expected to have oceans, increasing the likelihood that the Galilean satellites (e.g., Ganymede) would have an ocean, even without the presence of antifreeze such as ammonia.

6. Deep Earth

In addition to an interest in the earliest history of earth, there is a continuing effort on understanding the nature of the core and the interaction of the core with the mantle. One example of this work concerns the possibility that a small amount of liquid iron finds its way into the lowermost mantle through a suction process provided by the deviatoric stress that mantle convection inevitably provides. if the mantle can develop permeability, then the penetration distance of the iron is of order a kilometer. This may have relevance to some aspects of core-mantle coupling and chemical interaction.

Here is a publication describing aspects of this work (Kanda and Stevenson, 2006).

7. Some Other Topics

Here is a recent review on the formation of giant planets (to be published as Lissauer and Stevenson. 2006, in Protostars and Planets V).

8. Missions

I am involved in Juno, a New Frontiers class mission (PI Scott Bolton, SWRI) currently scheduled for launch in 2010. We will place a polar orbiter around Jupiter and obtain very high accuracy gravity and magnetic field data as well as water abundance by microwave sounding.

9. Students and Collaborators: Past, Present and Future

Jun-jun Liu completed her Ph. D. thesis with me in 2006. Kaveh Pahlevan is a planetary science graduate student who is currently working with me on lunar formation and related Earth and planet formation & evolution issues. Ann Marie Cody (grad student in astronomy) is working with me on the gravity field and density distribution within giant planets. Tais Dahl (graduate student at University of Copenhagen) has worked with me on Hf-W and core formation. Victor Tsai, grad student at Harvard, worked with me on True Polar Wander while an undergrad at Caltech. Undergraduates often work with me, usually through Ph 11 but also sometimes through the SURF program. High school students have also worked with me. Ari Berlin (freshman at Yale, beginning 2006) has worked with me on Jupiter's magnetic field and Sean Wahl (senior at Troy High School, Fullerton) has worked with me on the number and nature of plates required for a sustainable plate tectonic world.

Past students have included Jonathan Lunine (professor at University of Arizona), Huw Davies (Lecturer at Cardiff University of Liverpool) and Paul Tackley (professor at ETH in Zurich). There are always plenty of opportunities for students with a strong physics background.

9. Fun Stuff

Here is a Physics Today article I wrote about earthquakes and tsunamis.

10. Crazy Stuff

One of my speculations is about the possibility of interstellar planets Stevenson (1999). During planet formation, rock and ice embryos of order Earth's mass may be formed and some of these may be ejected from the solar system. They can retain molecular hydrogen-rich atmospheres that, upon cooling, have basal pressures of 102 -104 bars. Pressure-induced far IR opacity of H2 prevents such a body from eliminating its internal radioactive heat except by developing an extensive adiabatic-convective atmosphere, so that although the effective temperature of the body is of order 30K, its surface temperature can exceed the melting point of water. These bodies will be difficult to detect.

Here is the long version of the paper on interstellar planets (short version was published as Stevenson, 1999) It contains many details not in the Nature piece.

I have also published a "modest proposal" for a mission to earth's core. There are many practical difficulties with such a mission, and the paper was to a large extent not a practical suggestion but a provocation to get people thinking about going down rather than just going up (i.e., space missions). However, the basic physics of gravity driven fluid-filled cracks is sound. The short and less detailed version of which was published as Stevenson (2003a).

11. References

Additional publications may be found in my publications page.

  • Busse, F. H. 1983. A model of mean zonal flows in the major planets. Geophys. Astrophys. Fluid. Dyn. 23(2), 153-174.
  • Chambers, J. E. 2001. Making more terrestrial planets. Icarus 152 205-224.
  • Giampieri, G., M. K. Dougherty, E. J. Smith and C. T. Russell. 2006. A regular period for Saturn's magnetic field that may track its internal rotation Nature 441, p62-64 (May 4)
  • Guillot, T., Stevenson, D. J. Hubbard, W. B. and Saumon, D. 2004. The Interior of Jupiter. Chapter 3 in Jupiter (ed. F. Bagenal et al), Cambridge University Press.
  • Kanda, R. V. S., and D. J. Stevenson (2006), Suction mechanism for iron entrainment into the lower mantle, Geophys. Res. Lett., 33, L02310, doi:10.1029/2005GL025009.
  • Lissauer, J. J. , Stevenson, D. J. 2006 Formation of the Giant Planets. Protostars and Planets V, in press.
  • Machida, R. Y. Abe, The Evolution of an impact-generated partially vaporized circumplanetary disk, Astrophys. J. 617 (2004) 633-644.
  • Stevenson, D.J. Fluid dynamics of core formation. In Origin of the Earth, ed. H.E. Newsom, J.H. Jones, Oxford Un. Press, pp. 231-249, 1990.
  • Stevenson, D.J. Interior of Titan, Proceedings Symposium on Titan, publ. European Space Agency (Noordwijk, Netherlands) pp. 29-33, 1992.
  • Stevenson, D. J. Possibility of Life-sustaining Interstellar Planets. Nature, 400, p32, 1999.
  • Stevenson, David J. Mission to Earth's Core - A Modest Proposal. Nature, 423, 239-240, 2003a.
  • Stevenson, David J. Planetary magnetic fields. 2003b. Earth and Planetary Science Letters, 208, 1-11.
  • Stevenson, D. J. A new spin on Saturn. 2006. Nature 441, 34-35 (May 4).
  • Thompson, C. , Stevenson, D.J. 1988. Gravitational Instability in Two-Phase Disks and the Origin of the Moon, Astrophys. J. 333 (1988) 452-481.
  • Ward, W. R. and Canup, R.M. 2006. The obliquity of Jupiter. Astrophysical Journal, 640:L91–L94

Publications

Refereed Papers | Reviewed Articles | Miscellaneous

A. Papers in Refereed Journals

* A1. Clark, D.H. and D.J. Stevenson. A fast correlation method for studying drifting patterns associated with ionospheric irregularities. Australian J. Phys. 23, 947- 949, 1970.

* A2. Stevenson, D.J. Optical absorption in the alkali metals: Detailed calculations. Phys. Rev. B. 7, 2348-2358, 1973.

* A3. Stevenson, D.J. and N.W. Ashcroft. Conduction in fully ionized liquid metals. Phys. Rev. A. 9, 782-789, 1974.

* A4. Stevenson, David. Planetary magnetism. Icarus 22, 403-415, 1974.

* A5. Stevenson, D.J. Dynamo generation in Mercury. Nature 256, 634, 1975.

* A6. Stevenson, D.J. Does metallic ammonium exist? Nature 258, 222-223, 1975.

* A7. Stevenson, D.J. Thermodynamics and phase separation of dense fully ionized hydrogen- helium fluid mixtures. Phys. Rev. B. 12, 3999-4007, 1975.

* A8. Salpeter, E.E. and D.J. Stevenson. Heat transport in a stratified two-phase fluid. Phys. Fluids 19, 402-409, 1976.

* A9. Stevenson, D.J. Miscibility gaps in fully pressure-ionized binary alloys. Phys. Lett. 58A, 282-284, 1976.

* A10. Stevenson, D.J. Hydrogen in the Earth's core. Nature 268, 130, 1977.

* A11. Stevenson, D.J. and E.E. Salpeter. The phase diagram and transport properties for hydrogen-helium fluid planets. Astrophys. J. Supplement 35, 221-237, 1977.

* A12. Stevenson, D.J. and E.E. Salpeter. The dynamics and helium distribution in hydrogen-helium fluid planets. Astrophys. J. Supplement 35, 239-261, 1977.

* A13. Stevenson, D.J. A semitheory for semiconvection. Proc. Astron. Soc. Australia 3,
165-166, 1977.

* A14. Stevenson, D.J. Immiscibilities in cold, degenerate stars. Proc. Astron. Soc. Australia 3, 167-168, 1977.

* A15. Stevenson, D.J. and J.S. Turner. Angle of subduction. Nature 270, 334-336, 1977.

* A16. McElhinny, M.W., S.R. Taylor and D.J. Stevenson. Limits to the expansion of Earth, Moon, Mars and Mercury and to changes in the gravitational constant. Nature 271, 316-321, 1978.

* A17. Stevenson, D.J. Brown and Black Dwarfs: Their structure, evolution and contribution to the missing mass. Proc. Astron. Soc. Australia 3, 227-229, 1978.

* A18. Stevenson, David J. Turbulent thermal convection in the presence of rotation and a magnetic field: A heuristic theory. Geophys. Astrophys. Fluid Dynamics 12, 139-169, 1979.

* A19. Stevenson, D.J. Semiconvection as the occasional breaking of weakly amplified internal waves. Monthly Notices R. Astron. Soc. 187, 127-144, 1979.

* A20. Stevenson, D.J. Solubility of helium in metallic hydrogen. J. Phys. F: Metal Phys. 9, 791-800, 1979.

* A21. Merrill, R.T., M.W. McElhinny, and D.J. Stevenson. Evidence for long term asymmetries in the Earth's magnetic field and possible implications for dynamo theories. Phys. Earth Planet. Int. 20, 75-82, 1979.

* A22. Stevenson, D.J. Applications of liquid state physics to the Earth's core. Phys. Earth Planet. Int. 22, 42-52, 1980.

* A23. Stevenson, D.J. A eutectic in carbon-oxygen white dwarfs? J. de Physique Colloque C2, 61-64, 1980.

* A24. Schubert, Gerald, David Stevenson and Patrick Cassen. Whole planet cooling and the radiogenic heat source contents of the Earth and Moon. J. Geophys. Res. 85, 2531-2538, 1980.

* A25. Stevenson, D.J. Saturn's luminosity and magnetism. Science 208, 746-748, 1980.

* A26. Stevenson, D.J. Lunar asymmetry and paleomagnetism. Nature 287, 520-521, 1980.

* A27. Schubert, G., D.J. Stevenson and K. Ellsworth. Internal structures of the Galilean satellites. Icarus 47, 46-59, 1981.

* A28. Stevenson, D.J. Models of the Earth's core. Science 214, 611-619, 1981.

* A29. Stevenson, D.J. Volcanism and igneous processes in small icy satellites. Nature 298, 142-144, 1982.

* A30. Stevenson, D.J. Reducing the nonaxisymmetry of a planetary dynamo and an application to Saturn. Geophys. Astrophys. Fluid Dyn. 21, 113-127, 1982.

* A31. Stevenson, D.J. Formation of the giant planets. Planet. Sp. Sci. 30, 755-764, 1982.

* A32. Lunine, J.I. and D.J. Stevenson. Formation of the Galilean satellites in a gaseous nebula. Icarus 52, 14-39, 1982.

* A33. Stevenson, D.J. Anomalous bulk viscosity of two-phase fluids and implications for planetary interiors. J. Geophys. Res. 88, 2445-2453, 1983.

* A34. Stevenson, D.J., Spohn, T., and Schubert, G. Magnetism and thermal evolution of the terrestrial planets. Icarus 54, 466-489, 1983.

* A35. Friedson, A.J. and Stevenson, D.J. Viscosity of rock-ice mixtures and application to the evolution of icy satellites. Icarus 56, 1-14, 1983

* A36. Lunine, J.I., Stevenson, D.J. and Yung, Y.L. Ethane ocean on Titan. Science, 222, 1229-1230, 1983.

* A37. Stevenson, D.J. The energy flux number and three types of planetary dynamo. Astronomische Nachrichten, 305, 257-264, 1984.

* A38. Scott, D. R. and Stevenson, D.J. Magma Solitons. Geophys. Res. Lett., 11, 1161- 1164, 1984.

* A39. Lunine, J.I. and Stevenson, D.J. Thermodynamics of clathrate hydrate at low and high pressures with application to the outer solar system. Astrophys. J. Suppl., 58 493-531, 1985.

* A40. Lunine, J.I. and Stevenson, D.J. Physical state of volatiles on the surface of Triton. Nature 317, 238-240 1985.

* A41. Lunine, J.I. and Stevenson, D.J. Physics and Chemistry of Sulfur Lakes on Io. Icarus 64, 345-367, 1985.

* A42. Scott, D.R., Stevenson, D.J., and Whitehead, J.A. Observations of solitary waves in a deformable pipe. Nature 319, 759-761, 1986.

* A43. Stevenson, D.J. and Potter, B.E. Titan's latitudinal temperature distribution and seasonal cycle. Geophys. Res. Lett. 13, 93-96, 1986.

* A44. Ojakangas, G.W. and Stevenson, D.J. Episodic volcanism of tidally heated satellites with application to Io. Icarus 66, 341-358, 1986.

* A45. Scott, D.R. and Stevenson, D.J. Magma ascent by porous flow. J. Geophys. Res. 91, 9283-9296, 1986.

* A46. Stevenson, D.J. and Lunine, J.I. Mobilization of cryogenic ice in outer solar system satellites. Nature 323, 46-48, 1986.

* A47. Stevenson, D.J. On the role of surface tension in the migration of melts and fluids. Geophys. Res. Lett. 13, 1149-1152, 1986.

* A48. Kirk, R.L. and Stevenson, D.J. Thermal evolution of a differentiated Ganymede and implications for surface features. Icarus 69, 91-135, 1987.

* A49. Stevenson, D.J. Limits on lateral density and velocity variations in the Earth's outer core. Geophys, J. Roy. Astron. Soc. 88, 311-319, 1987.

* A50. Lunine, J.I. and Stevenson, D.J. Clathrate and ammonia hydrates at high pressure: Application to the Origin of Methane on Titan. Icarus, 70, 61-77, 1987.

* A51. Kirk, R.L. and Stevenson, D.J. Hydromagnetic implications of zonal flows in the giant planets. Astrophys. J., 316, 836-846, 1987.

* A52. Stevenson, D.J. Mercury's magnetic field: A thermoelectric dynamo? In Earth Planet. Sci. Lett. 82, 114-120, 1987.

* A53. Webb, E.K. and Stevenson, D.J. Subsidence of topography on Io. Icarus, 70, 348-353, 1987.

* A54. Crawford, G.D. and Stevenson, D.J. Gas-driven water volcanism and the resurfacing of Europa. Icarus 73, 66-79, 1988.

* A55. Stevenson, D.J. and Lunine, J.I. Rapid formation of Jupiter by diffusive redistribution of water vapor in the solar nebula. Icarus 75, 146-155, 1988.

* A56. Maher, K.A. and Stevenson, D.J. Impact frustration of the origin of life. Nature 331, 612-614, 1988.

* A57. Thompson, C. and Stevenson, D.J. Gravitational instability of two-phase disks and the origin of the moon. Astrophys. J. 333, 452-481, 1988.

* A58. Stevenson, D.J. and McNamara, S.C. Background heatflow of hotspot planets: Io and Venus. Geophys. Res. Lett. 15, 1455-1458, 1988.

* A59. Scott, D.R. and Stevenson, D.J. A self-consistent model of melting, magma migration and buoyancy-driven circulation beneath mid-ocean ridges. J. Geophys. Res. 94, 2973-2988, 1989.

* A60. Kirk, R.L. and Stevenson, D.J. The competition between thermal contraction and differentiation in the stress history of the Moon. J. Geophys. Res., 94, 12133-12144, 1989.

* A61. Ojakangas, G.W. and Stevenson, D.J. Thermal state of an ice shell on Europa. Icarus 81, 220-241, 1989.

* A62. Ojakangas, G.W. and Stevenson, D.J. Polar wander of a synchronously rotating satellite with application to Europa. Icarus, 81 242-270, 1989.

* A63. Stevenson, D.J. Spontaneous small-scale segregation in partial melts undergoing deformation. Geophys.Res.Lett. 16, 1067-1070, 1989.

* A64. Cynn, H-C., Boone, S., Koumvakalis, A., Nicol, M. and Stevenson, D.J. Phase diagram for ammonia-water mixtures at high pressures: Implications for icy satellites. Proc. Lunar & Planet. Sci. Conf. XIX, 433-441, 1989.

* A65. Stevenson, D.J. Chemical heterogeneity and imperfect mixing in the solar nebula. Astrophys. J. 348, 730-737, 1990.

* A66. Eluszkiewicz, J. and Stevenson, D.J. Rheology of solid methane and nitrogen: An application to Triton. Geophys. Res. Lett. 17, 1753-1756, 1990.

* A67. Kohler, Monica D. and Stevenson, David J. Modeling core fluid motions and the drift of magnetic field patterns at the CMB by use of Topography obatained by seismic inversion. Geophys. Res. Lett. 17, 1473-1476, 1990.

* A68. Herrick, David L. and Stevenson, D.J. Extensional and compressional instabilities in icy satellite lithospheres. Icarus 85, 191-204, 1990.

* A69. Davies, Huw J. and Stevenson, D.J. Thermal model of Subduction Zone. J. Geophys. Res. 97, 2037-2070, 1992.[Correction: Davies, J. H., Thorton, A. and Stevenson, D. J. J. Geophys. Res. 99, 20059. 1994].

* A70. Solomatov, V. and Stevenson, D.J. Suspension in convective layers and style of differentiation of a terrestrial magma ocean. J. Geophys. Res., 98, 5375-5390, 1993.

* A71. Solomatov, V. and Stevenson, D.J. Non-fractional crystallization of a terrestrial magma ocean. J. Geophys. Res. 98, 5407-5418, 1993.

* A72. Solomatov, V. and Stevenson, D.J. Kinetics of crystal growth in a terrestrial magma ocean. J. Geophys. Res. 98, 5391-5406, 1993.

* A73. Tackley, P.J., Stevenson, D.J., Glatzmaier, G.A. and Schubert, G. Effects of an endothermic phase transition at 670 km depth on spherical mantle convection. Nature, 361, 699-704, 1993.

* A74. Solomatov, V. S., Olson. P. and Stevenson, D.J. Entrainment from a bed of particles by thermal convection. Earth Planet. Sci. Lett. 120 387-393, 1993.

* A75. Tanimoto, T. and Stevenson, D.J. Seismic constraints on a model of partial melts under ridge axes. J. Geophys. Res. 99 4549-4558, 1994.

* A76. Solomatov, V. and Stevenson, D. J. Can sharp seismic discontinuities be caused by non-equilibrium phase transitions? Earth Planet. Sci. Lett. 125 267-279, 1994.

* A77. Tackley, P., Stevenson, D. J., Glatzmaier, G. A. and Schubert, G. Effects of Multiple Phase Transitions in a 3-D Spherical Model of Convection in the Earth's mantle. J. Geophys. Res. 99 15877-15901, 1994.

* A78. Takata, T. and Stevenson, D.J. Despin mechanism for protogiant planets. Icarus 123 404-421, 1996.

* A79. Kemp, David V. and Stevenson, David J. A Tensile, Flexural model for the Initiation of subduction. Geophys. J. Int., 125 73-94, 1996.

* A80. Showman, A. P., Stevenson, D. J. and Malhotra, R. Coupled orbital and thermal evolution of Ganymede. Icarus, 129 367-383, 1997.

* A81. Khurana, K. K., Kivelson, M. G., Stevenson, D. J. , Schubert, G., Russell, C. T., Walker, R. J., and Polanskey, C. Induced magnetic fields as evidence for subsurface oceans in Europa and Callisto. Nature 395, 777-780, 1998.

* A82. Kivelson, M.G., Khurana, K.K., Stevenson, D.J., Bennett, L., Joy, S., Russell, C.T., Walker, R.J., Zimmer, C., and Polanskey, C. Europa and Callisto: Induced or intrinsic fields in a periodically varying plasma environment. J. Geophys. Res. 104 4609-4625, 1999.

* A83. Stevenson, D. J. Life-sustaining Planets in Interstellar Space? Nature 400 p 32 (July 1), 1999.

* A84. Nimmo, F. and Stevenson, D. J. The influence of early plate tectonics on the thermal evolution and magnetic field of Mars. J. Geophys. Res., 105, 11969-11979, May 25, 2000.

* A85. Weizman, A., Stevenson, D. J., Prialnik, D. and Podolak, M. Modeling the volcanism on Mars. Icarus 150 195-205, 2001.

* A86. Nimmo, F. and Stevenson, D. J. Estimates of Martian crustal thickness from viscous relaxation of topography. J. Geophys. Res. 106, 5085-5098 , 2001.

* A87. Stevenson, David J. Mission to Earth's Core -A Modest Proposal. Nature, 423, 239-240, 2003.

* A88. Kanda, R. V. S., and D. J. Stevenson (2006), Suction mechanism for iron entrainment into the lower mantle, Geophys. Res. Lett., 33, L02310, doi:10.1029/2005GL025009.

* A89. Tsai, V. and Stevenson, D.J. (2006) Theoretical constraints on true polar wander. Submitted.

* A90. Liu, J-j, Goldreich, P. and Stevenson, D. J. (2006)Ohmic Dissipation Constraint on Deep-seated Zonal Winds in Jupiter and Saturn. Submitted.

B. Review Articles, Conference Proceedings

* B1. Stevenson, D.J. Planetary magnetism. AIP Conf. Proc. USA 24, 781-784, 1975.

* B2. Stevenson, D.J. and E.E. Salpeter. Interior models of Jupiter. In Jupiter: Studies of the Interior, Atmosphere, Magnetosphere and Satellites, T. Gehrels, ed., (Univ. Arizona Press), p. 85-112, 1976.

* B3. Stevenson, D.J. The outer planets and their satellites. In The Origin of the Solar System, S.F. Dermott, ed., (John Wiley), p. 395-431, 1978.

* B4. Stevenson, D.J. and J.S. Turner. Fluid models of mantle convection. Chapter 8 in The Earth, Its Origin, Evolution and Structure, M.W. McElhinny (ed.), Academic Press, p. 227-263, 1979.

* B5. Stevenson, D.J. The condensed matter physics of planetary interiors. (invited review paper for the CNRS Int'l Colloq. Physics of Dense Matter: Europhysics Conf. Dense Plasmas, Paris, Sept. 17-22, 1979). J. de Physique Colloque C2, 53-59, 1980.

* B6. Schubert, G., K. Ellsworth and D.J. Stevenson. Ice in the interiors of Ganymede and Callisto. Proc. 3rd Colloq. Planetary Water, 36-40, 1980.

* B7. Stevenson, D.J. Interiors of the giant planets. Ann. Rev. Earth Planet. Sci. 10, 257- 295, 1982.

* B8. Stevenson, D.J. Planetary magnetic fields. Reports on Progress in Physics 46, 555-620, 1983.

* B9. Walker, J.C.G., C. Klein, D.J. Stevenson and M.R. Walter. Environmental evolution of the Archean early protoerozoic Earth. Ch. 11 of Origin and Evolution of the Earth's Earliest Biosphere: An Interdisciplinary Study, J.W. Schopf , ed. (Princeton University Press), pp. 260-290, 1983.

* B10. Stevenson, D.J. The nature of the Earth prior to the oldest known rock record (the Hadean Earth). Ch. 2 of Origin and Evolution of the Earth's Earliest Biosphere: An Interdisciplinary Study, J.W. Schopf , ed. (Princeton University Press), pp. 32- 40, 1983.

* B11. Stevenson, D.J. Condensed matter physics of planets: puzzles, progress and predictions. Mat. Res. Soc. Symp. Proc. 22, 357-368 (publ. Elsevier), 1984.

* B12. Stevenson, D.J. Interior and Surface of Titan. Part of Titan Chapter by Hunten et al., in Saturn, T. Gehrels, ed., Un. Arizona Press, pp. 743-759, 1984.

* B13. Hubbard, W.B. and Stevenson, D.J. Interior structure of Saturn. In Saturn, ed. T. Gehrels, Un. Arizona Press, pp. 47-87, 1984.

* B14. Stevenson, D.J. Composition, structure and evolution of Uranian and Neptunian satellites. In Uranus and Neptune, NASA Conf. Publ. 2330, pp. 405-423, 1984.

* B15. Stevenson, D.J. High pressure physics and chemistry in giant planets and their satellites. J. de Physique Colloque, C8 97-103, 1984.

* B16. Stevenson, D.J. Cosmochemistry and structure of the giant planets and their satellites. Icarus 62, 4-15, 1985.

* B17. Lunine, J.I. and Stevenson, D.J. Evolution of Titan's coupled Ocean-Atmosphere system and interaction of ocean with bedrock. Proceedings NATO Conference Ices in the Solar System, eds. J. Klinger et al., pp. 741-757, 1985.

* B18. Stevenson, D.J. Origin, evolution and structure of the giant planets. In The Solar System, ed., M. Kivelson, Rubey Colloquium Series, Vol. 4, Prentice-Hall Publ., pp. 254-274, 1986.

* B19. Stevenson, D.J., Harris, A.W. and Lunine, J.I. Origins of planetary satellites. In Satellites, ed. J. Burns, Un. Arizona Press, pp. 39-88, 1986.

* B20. Stevenson, D.J. High mass planets and low mass stars. In Astrophysics of Brown Dwarfs, ed. M. Kafatos, R. Harrington and S. Maran, Cambridge Un. Press, pp. 218-232, 1986.

* B21. Stevenson, D.J. Origin of the Moon: The Collision Hypothesis. Ann. Rev. Earth Planet.Sci. 15, 271-315, 1987.

* B22. Stevenson, D.J. and Scott, D.R. Melt migration in deformable media. In Structure and Dynamics of Partially Solidified Systems. NATO ASI Series, ed. D. Loper, pp.401-416, 1987.

* B23. Stevenson, D.J. The role of high pressure experiment and theory in our understanding of gaseous and icy planets. Shock Waves in Condensed Matter. Ed. S.C. Schmidt, N.C. Holmes; Elsevier, pp. 51-54, 1988.

* B24. Schubert, G., Ross, M.N., Stevenson, D.J., and Spohn, T. Mercury's thermal history and the generation of its magnetic field. In Mercury, ed. C. Chapman et al., University of Arizona Press, Tucson, pp. 429-460, 1988.

* B25. Stevenson, D.J. Formation and early evolution of the Earth. In Mantle Convection, ed. W.R. Peltier, Gordon & Breach, pp. 817-873, 1989.

* B26. Stevenson, D.J. Implications of the giant planets for the formation and evolution of Planetary Systems. In Formation and Evolution of Planetary Systems, ed. H. Weaver, Cambridge Un. Press, pp. 75-90, 1989.

* B27. Stevenson, D.J. Fluid dynamics of core formation. In Origin of the Earth, ed. H.E. Newsom, J.H. Jones, Oxford Un. Press, pp. 231-249, 1990.

* B28. Stevenson, D.J. and Scott, D.R. Mechanics of fluid-rock systems. Ann. Rev. Fluid Mech. 23, 305-339, 1991.

* B29. Stevenson, D.J. Giant planets and their satellites: What are the relationships between their properties and how they formed. Proceedings of NAS-USSRAS Workshop on Planetary Sciences, Moscow, ed. T.M. Donahue, National Academy Press, pp. 163-173, 1991.

* B30. Stevenson, D.J. The search for brown dwarfs. Ann. Rev. Astron. Astrophysics 29, 163-193, 1991.

* B31. Podolak, M., Hubbard, W.B. and Stevenson, D.J. Models of Uranus' interior and magnetic field. Uranus, ed. J. Bergstrahl and M. Matthews, Un. Arizona Press, pp.29-61, 1991.

* B32. Stevenson, D.J. Interior of Titan, Proceedings Symposium on Titan, publ. European Space Agency (Noordwijk, Netherlands) pp. 29-33, 1992.

* B33. Tackley, P. and Stevenson, D.J. A mechanism for spontaneous self-perpetuating volcanism on the terrestrial planets. NATO ASI: Flow and Creep in the Solar System, ed. D.B. Stone and S.K. Runcorn, pp. 307-321, 1993.

* B34. Kedar, S., Anderson, D.L. and Stevenson, D.J. Relationship between hotspots and mantle structure: Correlation with whole mantle seismic tomography. NATO ASI: Flow and Creep in the Solar System, ed. D.B. Stone and S.K. Runcorn, pp. 249-259, 1993.

* B35. Stevenson, D. J. Physico-chemical Processes in Planetary Evolution. Phil . Trans. R. Soc. Lond. A. 349, 171-179 , 1994.

* B36. Lissauer, J., Pollack, J.B., Wetherill, G.W. and Stevenson, D.J. Formation of the Neptune system. In Neptune, Un. Arizona Space Science Series, pp 37-108, 1995.

* B37. Hubbard, W.B., Podolak, M. and Stevenson, D.J. The interior of Neptune. In Neptune, Un. Arizona Space Science Series, pp 109-138, 1995.

* B38. Stevenson, D. J. States of Matter in Massive Planets. Journal of Physics: Condensed Matter, 10, 11227-11234, 1998.

* B39. Pritchard, M. S. and Stevenson, D. J. Thermal constraints on the Origin of the Moon. Origin of the Earth and Moon (Eds. R. Canup and K. Righter), Un. Arizona Press, pp179-196, 2000.

* B40. Stevenson, David J. Mars Core and Magnetism. Nature 412, 214-219, 2001.

* B41. Stevenson, Introduction to Planetary Interiors. In "High Pressure Phenomena," Volume 147, International School of Physics Enrico Fermi, Edited by: G.L. Chiarotti , M. Bernasconi , L. Ulivi and R.J. Hemley . IOS Press, Amsterdam, 587-606, 2002.

* B42. Stevenson, David J. Planetary magnetic fields. Earth and Planetary Science Letters, 208, 1-11, 2003.

* B43. Stevenson, David J. Styles of Mantle Convection and their Influence on Planetary Evolution. Comptes Rendues de L'Academie des Sciences, 335, 99-111, 2003.

* B44. Kono, Masaru and Stevenson, David J. Dynamo Processes and Magnetic Field of the Earth and Planets. J. Seismo. Soc. Japan 56 311-325, 2003. [In Japanese].

* B45. Stevenson, D. J. Formation of Giant Planets. The Search for other Worlds, Fourteenth Astrophysics conference, ed. S. S. Holt and D. Deming, publ. American Institute of Physics (N. Y.) Conference Proceedings No .713, pp 133-141, 2004.

* B46. Guillot, T., Stevenson, D. J. Hubbard, W. B. and Saumon, D. The Interior of Jupiter. Chapter 3 in Jupiter (ed. F. Bagenal et al), Cambridge University Press, 2004.

C. Miscellaneous (Popular Articles, book reviews, commentaries)

* C1. Stevenson, D.J. Induced suction and lithospheric plate pull. In Matters Arising, Nature 274, 346, 1978.

* C2. Stevenson, D.J. Review of Magnetic field generation in electrically conducting fluids, by H.K. Moffatt, Cambridge University Press, London/New York, 1978, x+343 pp. Icarus 37, 358-359, 1979 .

* C3. Stevenson, David J. Review of The Saturn system, Donald M. Hunten and David Morrison (ed.), NASA Conf. Publ. 2068, NASA, Washington, DC, vi+420 pp, 1978. EOS 60, 774, 1979 .

* C4. Stevenson, D.J. Review of Interiors of the Planets, A.H. Cook (Cambridge University Press, 1980). Geophys. Astrophys. Fluid Dyn. 18, 328-330, 1981.

* C5. Stevenson, D.J. Onions or plum puddings? Engineering and Science 66, 16-21, 1983.

* C6. Stevenson, D.J. Review of Satellites of Jupiter, David Morrison (ed). EOS 64, 507- 508, 1983.

* C7. Stevenson, D.J. No clear consensus on planetary origins. Geotimes 29, 15-16, 1984.

* C8. Stevenson, D.J. Physics and chemistry of planets debated. Geotimes 29, 18- 19,1984.

* C9. Stevenson, D.J. Review of Planets and their atmospheres by J.S. Lewis and R.G. Prinn. Icarus, 60 720-721, 1984.

* C10. Stevenson, D.J. Melt migration in the Earth. Nature 317, 767-768, 1985.

* C11. Stevenson, D.J. Comparative Planetology (Meeting Report). EOS 67, 163, 1986.

* C12. Stevenson, D.J. An ocean in Uranus? The Planetary Report 6, 16, 1986.

* C13. Stevenson, D.J. Book review of Origin of the Moon, Eds. Hartmann, Phillips and Taylor, Lunar Planet. Inst., Science 234, 1016-1017, 1986.

* C14. Stevenson, D.J. Greenhouses and magma oceans. Nature 335, 587-588, 1988.

* C15. Stevenson, D.J. Review of The Structure of the Planets by John Elder. Phys. Earth Planet. Int. 53, 183-184, 1988.

* C16. Stevenson, D.J. Looking ahead to Neptune. Sky and Telescope 77, 481-483, 1989.

* C17. Stevenson, D.J. Hydrogen: molecules, metal or plasma? Physics World 2, 17, 1989.

* C18. Stevenson, D.J. Review of Origin and Evolution of Planetary and Satellite Atmospheres. In Science 245, 1402-1403, 1989.

* C19. Stevenson, D.J. Stalking the magma ocean. Nature 355, 301, 1992

* C20. Stevenson, D.J. An Insiders View (Review of Deep Interior of the Earth by J.A. Jacobs.) Nature 356, 396, 1992.

* C21. Stevenson, D. J. Origin of the Moon.Text of Invited lecture (privately published), Sackler Institute, Tel Aviv University, 1993.

* C22. Stevenson, D. J. Mantle Geophysics: Weakening under stress. Nature 372 129-130, 1994.

* C23. Stevenson, D. J. Light from tungsten on core construction. Nature 378 763-764, 1995.

* C24. Stevenson, D. J. The subtle taste of Jupiter. Nature 379 495-496, 1996.

* C25. Stevenson, D. J. When Galileo met Ganymede. Nature 384 511-512, 1996.

* C26. Stevenson D. J. The earth's mantle - Composition, structure, and evolution, Science 281 1462-1463, 1998.

* C27 Stevenson, D. J. An ocean in Callisto? The Planetary Report 19 no 3 (May-June), 7-11, 1999.

* C28 Stevenson, David J. Planetary Science: A Space Odyssey. Science 287 997-1005, 2000.

* C29 Stevenson, David. Europa's ocean - the Case Strengthens. Science 289 1305-1307, 2000.

* C30. Stevenson, David J. Jupiter and its Moons. Science 294 71-72, 2001.

* C31. Stevenson, David J. Planetary Oceans, Sky and Telescope, pp38-44, November, 2002.

* C32. Stevenson, David J. Insightful Storytelling on Geodynamics. [Review of The Dynamic Structure of the Deep Earth by S-I. Karato, Princteon University Press, 2003], Science 301 1674, 2003.

* C33. Stevenson, David J. Planetary Diversity. Physics Today pp43-48, April, 2004.

* C34. Stevenson, David. Inside History in Depth. Nature 428 476-477, 2004.

* C35. Stevenson, David J. Book Review: Exploring mercury: The Iron Planet, Robert G. Strom and Ann L. Sprague, Springer Praxis Books, EOS 85, 192, May 2004.

* C36. Stevenson, David J. Volcanoes on Quaoar? Nature 432 681-682, December 2004.

* C37 Stevenson, David J. Tsunamis and Earthquakes: What Physics is interesting? Physics Today, June 2005, pp10-11.

* C38 Stevenson, David J. A new spin on Saturn. Nature 441, 34-35, 2006.

2024-25
Ge 131. Planetary Structure and Evolution. 9 units (3-0-6); third term, 2024-25. Prerequisites: instructor's permission. A critical assessment of the physical and chemical processes that influence the initial condition, evolution, and current state of planets, including our planet and planetary satellites. Topics to be covered include a short survey of condensed-matter physics as it applies to planetary interiors, remote sensing of planetary interiors, planetary modeling, core formation, physics of ongoing differentiation, the role of mantle convection in thermal evolution, and generation of planetary magnetic fields.
Instructor: Stevenson
2023-24
Ge 131. Planetary Structure and Evolution. 9 units (3-0-6); third term, 2023-24. Prerequisites: instructor's permission. A critical assessment of the physical and chemical processes that influence the initial condition, evolution, and current state of planets, including our planet and planetary satellites. Topics to be covered include a short survey of condensed-matter physics as it applies to planetary interiors, remote sensing of planetary interiors, planetary modeling, core formation, physics of ongoing differentiation, the role of mantle convection in thermal evolution, and generation of planetary magnetic fields.
Instructor: Stevenson
2022-23
Ge 131. Planetary Structure and Evolution. 9 units (3-0-6); third term, 2022-23. Prerequisites: instructor's permission. A critical assessment of the physical and chemical processes that influence the initial condition, evolution, and current state of planets, including our planet and planetary satellites. Topics to be covered include a short survey of condensed-matter physics as it applies to planetary interiors, remote sensing of planetary interiors, planetary modeling, core formation, physics of ongoing differentiation, the role of mantle convection in thermal evolution, and generation of planetary magnetic fields.
Instructor: Stevenson
2021-22
Ge 131. Planetary Structure and Evolution. 9 units (3-0-6); third term, 2021-22. Prerequisites: instructor's permission. A critical assessment of the physical and chemical processes that influence the initial condition, evolution, and current state of planets, including our planet and planetary satellites. Topics to be covered include a short survey of condensed-matter physics as it applies to planetary interiors, remote sensing of planetary interiors, planetary modeling, core formation, physics of ongoing differentiation, the role of mantle convection in thermal evolution, and generation of planetary magnetic fields.
Instructor: Stevenson
2020-21
Ge 131. Planetary Structure and Evolution. 9 units (3-0-6); third term, 2020-21. Prerequisites: instructor's permission. A critical assessment of the physical and chemical processes that influence the initial condition, evolution, and current state of planets, including our planet and planetary satellites. Topics to be covered include a short survey of condensed-matter physics as it applies to planetary interiors, remote sensing of planetary interiors, planetary modeling, core formation, physics of ongoing differentiation, the role of mantle convection in thermal evolution, and generation of planetary magnetic fields.
Instructor: Stevenson
2019-20
Ge 131. Planetary Structure and Evolution. 9 units (3-0-6); third term, 2019-20. Prerequisites: instructor's permission. A critical assessment of the physical and chemical processes that influence the initial condition, evolution, and current state of planets, including our planet and planetary satellites. Topics to be covered include a short survey of condensed-matter physics as it applies to planetary interiors, remote sensing of planetary interiors, planetary modeling, core formation, physics of ongoing differentiation, the role of mantle convection in thermal evolution, and generation of planetary magnetic fields.
Instructor: Stevenson
Course Website: http://web.gps.caltech.edu/classes/ge131/