SHAWN D DOMAGAL-GOLDMAN

SHAWN D DOMAGAL-GOLDMAN

  • RESEARCH AST, PLANETARY STUDIES
  • 301.614.6245 | 111.111.1111
  • NASA/GSFC
  • Mail Code: 699
  • Greenbelt , MD 20771
  • Employer: NASA
  • Brief Bio

    My research focuses on ascertaining as much as possible about "alien planets" using sparse data sets. For early Earth and other terrestrial planets, I work on utilizing isotopic trends as proxies for atmospheric processes and elemental cycling. This includes work on the fundamental controls on Fe isotope fractionation and on global controls on mass-independent Sulfur isotope fractionation (S-MIF). For extrasolar planets, I help develop spectroscopy-based characterization techniques that can inform us about a planet's surface climate, habitability, and ecosystems.

    I'm also extremely passionate about science communication, and believe it is our responsibility as publicly-funded scientists to bring the results of our research back to the public. To this end, I've helped organize FameLab events in the US... and am always looking for new opportunities to talk about NASA science in public forums.

    Selected Public Outreach

    Featured Stories 2016 - Present
    https://www.quantamagazine.org/20160202-scientists-debate-signatures-of-alien-life/

    This is an article in Quanta Magazine that discusses the complexities associated with the search for life on exoplanets. It starts with a description of the moment when I realized that O3 can build up on planets without life, in certain circumstances. You can see the paper that I published on that subject here.

    Research Interests

    Rocky Extrasolar Planet Characterization

    I am currently working on three aspects of terrestrial-sized extrasolar planet characterization:

    1.) the potential for "false positives" and "false negatives" for life to misinform our spectral analyses of these objects,

    2.) the degree to which we can constrain habitability of known or candidate extrasolar planets with current measurements, and prioritize future observations, and

    3.) mission/instrument design for exoplanet characterization.

    The tools I use for this are a series of models of the atmospheres of other planets, the spectra those planets produce, and the imaging of those spectra by exoplanet missions. The atmospheric models are what I spend most of my time developing. In the past, most of this work has been done as part of the Virtual Planetary Laboratory, using their 1-dimensional, altitude-dependent atmospheric models, but we are also partnering with the Goddard Institute for Space Science to develop a planetary 3D GCM based on their Earth GCM, ModelE.

    Modeling Archean Geochemical Proxies

    I am interested in using atmospheric models (photochemical and climatological) to recreate signals observed in the Archean rock record - a time period on Earth when there was life but no molecular oxygen (O2) in the atmosphere. This work will improve our understanding of the evolution of life on Earth, and inform our search for life on other planets as we learn more about the "most alien biosphere" we currently  have data on.

    This work is being done as part of the Virtual Planetary Laboratory, a lead node of the NASA Astrobiology Institute. Specifically, I'm working on the second task of that team, to "Characterize the Environment, Habitability and Biosignatures of the Earth Through Time." We want to uncover the history of biological metabolisms (e.g., methanogenesis, oxygenic photosynthesis, etc.) on the planet, and leverage that knowledge to simulate the biosignatures of the biosphere for different metabolic eras in the planet's history. This will give us a wider set of examples for the biospheres we can look for on extrasolar planets.

    The reason to focus on early Earth as an example of an extrasolar biosphere is that we have a rock record with which to constrain our conceptual and numerical models. The data in the rock record I find most useful are isotopic proxies, which can deliver a tremendous depth and breadth of information about early Earth. My role in the interpretation of these proxies is to propose hypotheses that can explain as many data sets as possible, and use atmospheric models to test whether the hypotheses can explain the data given reasonable boundary conditions. Ideally, we also use model outputs to propose new geological proxies to look for in tests of the hypotheses.

    Molecular Modeling of Astrobiologically-Significant Chemical Reactions

    This is a line of work that has lied dormant for a few years, but that I would be interested in reviving with the right collaborations or student or postdoctoral fellow in our group. In this research, we would utilize molecular modeling tools such as density functional theory to explore the reaction rate constants, equilibrium constants, and reaction pathways for chemical reactions of astrobiologal significance. For example, we could examine reactions that are relevant to the chemistry of planetary atmospheres, the production and preservation of isotopic proxies in the Earth's most ancient rocks, or the habitability of environments on other worlds.

    Positions/Employment

    2013 - Present

    Research Space Scientist

    NASA, Goddard Space Flight Center, Greenbelt, MD  
    7/2010 - 7/2012

    NASA Astrobiology Management Postdoctoral Fellow

    Oak Ridge Associated Universities, NASA Headquarters, Washington, DC
    7/2008 - 7/2010

    Research Associate

    Virtual Planetary Laboratory, University of Washington, Seattle, WA  

    Education

    Ph.D. in Astrobiology and Geosciences, August 2007
    Pennsylvania State University, University Park, PA
    Committee: J. F. Kasting (Co-advisor), J. D. Kubicki (Co-advisor), M. A. Arthur, J. O. Sofo
    Dissertation: Modeling Novel Isotopic Proxies for the Oxygenation of the Earth’s Surface

    M.S. in Geochemistry, May 2002
    University of Rochester, Rochester, NY
    Advisor: A. D. Anbar
    Thesis: Modeling Net Primary Production in the Archean as a Function of Temperature

    B.S. in Physics
    , May 2001
    University of Rochester, Rochester, NY
    Advisor: A. D. Anbar
    Thesis: Using Fe Isotope Ratios in Banded Iron Formations as a Potential Geothermometer

    Selected Publications

    Refereed

    Kopparapu, R. K., R. Ramirez, J. F. Kasting, et al. V. Eymet, T. D. Robinson, S. Mahadevan, R. C. Terrien, S. Domagal-Goldman, V. Meadows, and R. Deshpande. 2013. "Erratum: Habitable Zones Around Main-sequence Stars: New Estimates’' (2013, ApJ, 765, 131)." The Astrophysical Journal, 770: 82 [doi:10.1088/0004-637X/770/1/82]

    Zerkle, A. L., M. W. Claire, S. D. Domagal-Goldman, J. Farquhar, and S. W. Poulton. 2012. "A Bistable Organic-rich Atmosphere on the Neoarchaean Earth." Nature Geoscience, 5: 359–363 [doi:10.1038/ngeo1425]

    Kopparapu, R. K., R. Ramirez, J. F. Kasting, et al. V. Eymet, T. D. Robinson, S. Mahadevan, R. C. Terrien, S. Domagal-Goldman, V. Meadows, and R. Deshpande. 2012. "Habitable Zones Around Main-sequence Stars: New Estimates." The Astrophysical Journal, 765: 131.

    Domagal-Goldman, S. D., V. S. Meadows, M. W. Claire, and J. F. Kasting. 2011. "Using Biogenic Sulfur Gases as Remotely Detectable Biosignatures on Anoxic Planets.." Astrobiology, 11: 419–41 [doi:10.1089/ast.2010.0509]

    Domagal-Goldman, S. D., and V. S. Meadows. 2010. "Abiotic Buildup of Ozone." Pathways Towards Habitable Planets, 1–6:

    Domagal-Goldman, S. D., K. W. Paul, D. L. Sparks, and J. D. Kubicki. 2009. "Quantum Chemical Study of the Fe(III)-desferrioxamine B Siderophore complex—Electronic Structure, Vibrational Frequencies, and Equilibrium Fe-isotope Fractionation." Geochimica et Cosmochimica Acta, 73: 1–12 [doi:10.1016/j.gca.2008.09.031]

    Domagal-Goldman, S. D., J. F. Kasting, D. T. Johnston, and J. Farquhar. 2008. "Organic Haze, Glaciations and Multiple Sulfur Isotopes in the Mid-Archean Era." Earth and Planetary Science Letters, 269: 29–40 [doi:10.1016/j.epsl.2008.01.040]

    Domagal-Goldman, S. D., and J. D. Kubicki. 2008. "Density Functional Theory Predictions of Equilibrium Isotope Fractionation of Iron Due to Redox Changes and Organic Complexation." Geochimica et Cosmochimica Acta, 72: 5201–5216 [doi:10.1016/j.gca.2008.05.066]

    Haqq-Misra, J. D., S. D. Domagal-Goldman, P. J. Kasting, and J. F. Kasting. 2008. "A Revised, Hazy Methane Greenhouse for the Archean Earth.." Astrobiology, 8: 1127–37 [doi:10.1089/ast.2007.0197]

    Riccardi, A., S. Domagal-Goldman, F. U. Battistuzzi, and V. Cameron. 2006. "Astrobiology Influx to Astrobiology in Flux.." Astrobiology, 6: 397–399 [doi:10.1089/ast.2006.6.397]

    Brief Bio

    My research focuses on ascertaining as much as possible about "alien planets" using sparse data sets. For early Earth and other terrestrial planets, I work on utilizing isotopic trends as proxies for atmospheric processes and elemental cycling. This includes work on the fundamental controls on Fe isotope fractionation and on global controls on mass-independent Sulfur isotope fractionation (S-MIF). For extrasolar planets, I help develop spectroscopy-based characterization techniques that can inform us about a planet's surface climate, habitability, and ecosystems.

    I'm also extremely passionate about science communication, and believe it is our responsibility as publicly-funded scientists to bring the results of our research back to the public. To this end, I've helped organize FameLab events in the US... and am always looking for new opportunities to talk about NASA science in public forums.

    Selected Publications

    Refereed

    Kopparapu, R. K., R. Ramirez, J. F. Kasting, et al. V. Eymet, T. D. Robinson, S. Mahadevan, R. C. Terrien, S. Domagal-Goldman, V. Meadows, and R. Deshpande. 2013. "Erratum: Habitable Zones Around Main-sequence Stars: New Estimates’' (2013, ApJ, 765, 131)." The Astrophysical Journal 770 82 [doi:10.1088/0004-637X/770/1/82]

    Zerkle, A. L., M. W. Claire, S. D. Domagal-Goldman, J. Farquhar, and S. W. Poulton. 2012. "A Bistable Organic-rich Atmosphere on the Neoarchaean Earth." Nature Geoscience 5 359–363 [doi:10.1038/ngeo1425]

    Kopparapu, R. K., R. Ramirez, J. F. Kasting, et al. V. Eymet, T. D. Robinson, S. Mahadevan, R. C. Terrien, S. Domagal-Goldman, V. Meadows, and R. Deshpande. 2012. "Habitable Zones Around Main-sequence Stars: New Estimates." The Astrophysical Journal 765 131.

    Domagal-Goldman, S. D., V. S. Meadows, M. W. Claire, and J. F. Kasting. 2011. "Using Biogenic Sulfur Gases as Remotely Detectable Biosignatures on Anoxic Planets.." Astrobiology 11 419–41 [doi:10.1089/ast.2010.0509]

    Domagal-Goldman, S. D., and V. S. Meadows. 2010. "Abiotic Buildup of Ozone." Pathways Towards Habitable Planets 1–6

    Domagal-Goldman, S. D., K. W. Paul, D. L. Sparks, and J. D. Kubicki. 2009. "Quantum Chemical Study of the Fe(III)-desferrioxamine B Siderophore complex—Electronic Structure, Vibrational Frequencies, and Equilibrium Fe-isotope Fractionation." Geochimica et Cosmochimica Acta 73 1–12 [doi:10.1016/j.gca.2008.09.031]

    Domagal-Goldman, S. D., J. F. Kasting, D. T. Johnston, and J. Farquhar. 2008. "Organic Haze, Glaciations and Multiple Sulfur Isotopes in the Mid-Archean Era." Earth and Planetary Science Letters 269 29–40 [doi:10.1016/j.epsl.2008.01.040]

    Domagal-Goldman, S. D., and J. D. Kubicki. 2008. "Density Functional Theory Predictions of Equilibrium Isotope Fractionation of Iron Due to Redox Changes and Organic Complexation." Geochimica et Cosmochimica Acta 72 5201–5216 [doi:10.1016/j.gca.2008.05.066]

    Haqq-Misra, J. D., S. D. Domagal-Goldman, P. J. Kasting, and J. F. Kasting. 2008. "A Revised, Hazy Methane Greenhouse for the Archean Earth.." Astrobiology 8 1127–37 [doi:10.1089/ast.2007.0197]

    Riccardi, A., S. Domagal-Goldman, F. U. Battistuzzi, and V. Cameron. 2006. "Astrobiology Influx to Astrobiology in Flux.." Astrobiology 6 397–399 [doi:10.1089/ast.2006.6.397]

                                                                                                                                                                                            
    NASA Logo, National Aeronautics and Space Administration