Planetary Science

Planetary science underlies much of the research at the Geophysical Laboratory. We study the structure and composition of matter over a wide range of temperatures and pressures appropriate to planetary materials. Our goal is to understand the physical and chemical structures of planets to depths as far as our laboratory pressure capability can take us. We study the transformation of surface, mantle and core materials in dynamic processes that create structural and geochemical change during the evolution of planets.

Microscopic view of Jovian interiors calculated from first-principles theory.

Helium in molecular hydrogen		Helium in metallic hydrogen (B. Militzer)

We also study extraterrestrial materials that may have come from planets or planetary building blocks early in the solar system, such as meteorites and comets, in order to deduce the nature of the original material that made up the solar system and the evolution of this material, physically and chemically, during and after the formation of the solar system. We apply unique laboratory instrumentation and an array of expertise from mineral physics to geochemistry to organic chemistry to microbiology in this work. A particular focus is on insoluble organics in these samples and on what these materials can tell us about the evolution of organic chemistry in the solar system. The Laboratory is active in analyzing samples returned from space such as from the recent Stardust mission that returned samples of Comet Wild2.

Finally we work on finding measurements and instrumental techniques for identifying evidence of fossil life in geological materials. This evidence could consist of a particular distribution of minerals, elements or isotopes in a rock sample, or perhaps even morphologic evidence of fossil microbes and their chemical remains. We conduct field expeditions in Mars analog sites on earth to test these techniques and instruments, and staff members participate on flight instrument investigations to other planets to search for organic material and signs of past or current life. We have a fundamental interest in the evolution of complex chemistry on young planets and the how the transition takes place from chemistry to biology early in planetary history.

Recent Publications

3887            Alexander, C. M. O'D., G. D. Cody, M. Fogel, and H. Yabuta, Organics in meteorites - Solar or interstellar?, in Organic Matter in Space, S. Kwok and S. Sandford, eds., pp. 293-298, International Astronomical Union Symposium 251, Cambridge University Press, Cambridge, 2008.

3817            Cody, G. D., H. Ade, C. M. O'D. Alexander, T. Araki, A. Butterworth, H. Fleckenstein, G. Flynn, M. K. Gilles, C. Jacobsen, A. L. D. Kilcoyne, K. Messenger, S. A. Sandford, T. Tyliszczak, A. J. Westphal, S. Wirick, and H. Yabuta, Quantitative organic and light element analysis of Comet 81P/Wild 2 particles using C-, N-, and O-m-XANES, Meteoritics Planet. Sci. 43, 353-365, 2008.

3886            Cody, G. D., C. M. O'D. Alexander, A. L. D. Kilcoyne, and H. Yabuta, Unraveling the chemical history of the Solar System as recorded in extraterrstrial organic matter, in Organic Matter in Space, S. Kwok and S. Sandford, eds., pp. 277-284, International Astronomical Union Symposium 251, Cambridge University Press, Cambridge, 2008.

3857            Cody, G. D., C. M. O'D. Alexander, H. Yabuta, A. L. D. Kilcoyne, T. Araki, H. Ade, P. Dera, M. Fogel, B. Militzer, and B. O. Mysen, Organic thermometry for chondritic parent bodies, Earth Planet. Sci. Lett. 272, 446-455, 2008.

3814            Corgne, A., B. J. Wood, and Y. Fei, C- and S-rich molten alloy immiscibility and core formation of planetesimals, Geochim. Cosmochim. Acta 72, 2409-2416, 2008.

3920            Coustenis, A., et al., TandEM:  Titan and Enceladus mission, Exp. Astron. 23, 893-946, 2009.

3929            Day, J. M. D., R. D. Ash, Y. Liu, J. J. Bellucci, D. Rumble III, W. F. McDonough, R. J. Walker, and L. A. Taylor, Early formation of evolved asteroidal crust, Nature 457, 179-182, 2009.

3815            Dera, P., B. Lavina, L. A. Borkowski, V. B. Prakapenka, S. R. Sutton, M. L. Rivers, R. T. Downs, N. Z. Boctor, and C. T. Prewitt, High-pressure polymorphism of Fe₂P and its implications for meteorites and Earth's core, Geophys. Res. Lett. 35, L10301, 10.1029/2008GL033867, 2008.

3932            Fiquet, G., J. Badro, E. Gregoryanz, Y. Fei, and F. Occelli, Sound velocity in iron carbide (Fe₃C) at high pressure:  implications for the carbon content of the Earth’s inner core, Phys. Earth Planet. Inter. 172, 125-129, 2009.

3805            Fries, M., and A. Steele, Graphite whiskers in CV3 meteorites, Science 320, 91-93, 2008.

3860            Gao, L., B. Chen, J. Wang, E. E. Alp, J. Zhao, M. Lerche, W. Sturhahn, H. P. Scott, F. Huang, Y. Ding, S. V. Sinogeikin, C. C. Lundstrom, J. D. Bass, and J.  Li, Pressure-induced magnetic transition and sound velocities of Fe₃C:  implications for carbon in the earth's inner core, Geophys. Res. Lett. 35, L17306, 10.1029/2008GL034817, 2008.

3905            Glass, B. P., and M. Fries, Micro-Raman spectroscopic study of fine-grained, shock-metamorphosed rock fragments from the Australasian microtektite layer, Meteoritics Planet. Sci. 43, 1487-1496, 2008.

3894            Goncharov, A. F., B. D. Haugen, V. V. Struzhkin, P. Beck, and S. D. Jacobsen, Radiative conductivity in the Earth’s lower mantle, Nature 456, 231-234, 2008.

____            Hazen, R. M., and J. S. Trefil, Science Matters, 2nd ed., Anchor Books, New York, in press.

3899            Lin, J.-F., H. Watson, G. Vankó, E. E. Alp, V. B. Prakapenka, P. Dera, V. V. Struzhkin, A. Kubo, J. Zhao, C. McCammon, and W. J. Evans, Intermediate-spin ferrous iron in lowermost mantle post-perovskite and perovskite, Nature Geosci. 1, 688-691, 2008.

3866            Litasov, K. D., Y. Fei, E. Ohtani, T. Kuribayashi, and K. Funakoshi, Thermal equation of state of magnesite to 32 GPa and 2073 K, Phys. Earth Planet. Inter. 168, 191-203, 2008.

3845            Lundin, S., K. Catalli, J. Santillán, S.-H. Shim, V. B. Prakapenka, M. Kunz, and Y. Meng, Effect of Fe on the equation of state of mantle silicate perovskite over 1 Mbar, Phys. Earth Planet. Inter. 168, 97-102, 2008.

3825            Martins, Z., O. Botta, M. L. Fogel, M. A Sephton, D. P. Glavin, J. S. Watson, J. P. Dworkin, A. W. Schwartz, and P. Ehrenfreund, Extraterrestrial nucleobases in the Murchison meteorite, Earth Planet. Sci. Lett. 270, 130-136, 2008.

3896            McCanta, M. C., A. H. Treiman, M. D. Dyar, C. M. O'D. Alexander, D. Rumble III, and E. J. Essene, The LaPaz Icefield 04840 meteorite:  mineralogy, metamorphism, and origin of an amphibole- and biotite-bearing R chondrite, Geochim. Cosmochim. Acta 72, 5757-5780, 2008.

3930            Murakami, M., S. V. Sinogeikin, K. Litasov, E. Ohtani, and J. D. Bass, Single-crystal elasticity of iron-bearing majorite to 26 GPa:  implications for seismic velocity structure of the mantle transition zone, Earth Planet. Sci. Lett. 274, 339-345, 2008.

3818            Rotundi, A., G. A. Baratta, J. Borg, J. R. Brucato, H. Busemann, L. Colangeli, L. D'Hendecort, Z. Djouadi, G. Ferrini, I. A. Franchi, M. Fries, F. Grossemy, L. P. Keller, V. Mennella, K. Nakamura, L. R. Nittler, M. E. Palumbo, S. A. Sandford, A. Steele, and B. Wopenka, Combined micro-Raman, micro-infrared, and field emission scanning electron microscope analyses of Comet 81P/Wild 2 particles collected by Stardust, Meteoritics Planet. Sci. 43, 367-397, 2008.

____            Steele, A., D. W. Beaty, J. Amend, R. Anderson, L. Beegle, L. G. Benning, J. Bhattacharya, D. Blake, W. Brinckerhoff, J. Biddle, S. Cady, P. Conrad, J. Lindsay, R. Mancinelli, G. Mungas, J. Mustard, K. Oxnevad, J. Toporski, and H. Waite, The science goals of the Astrobiology Field Laboratory (AFL).  Report of the MEPAG Science Steering Group, Astrobiology, in press.

(updated 03/11/09)