PTYS/LPL Faculty

Thomas Zega


  • Diana Bolser (Chemistry)
  • Michelle Thompson (PTYS)
Tom Zega
Assistant Professor
Cosmochemistry, Planetary materials
Ph.D., 2003, Arizona State University

Kuiper   #522

Years with LPL:  2011 to present


Dr. Zega applies a microscopy- and microanalysis-based approach to study the chemical and physical evolution of the early solar system and ancient stars. His current efforts are focused on the origin of refractory inclusions, presolar grains, primitive organics, interplanetary dust particles, and material retrieved from the Stardust mission. He uses ultrahigh-resolution ion- and electron-microscopy techniques, including focused-ion-beam scanning-electron microscopy and transmission electron microscopy, to determine the composition and structure of these materials at scales ranging from millimeters down to a fraction of a nanometer. Knowledge of these intimate details of planetary materials provides incomparable insights into the origin of our solar system and ancient stars.

Planetary Materials Research Group


  • Microstructural and Crystal-Chemical Studies of Presolar Oxides: NASA Cosmochemistry Program
  • Pilot Study: The Search for Biosignatures in Rock Microhabitats from the Atacama Desert, an Analog for Mars Environment, NASA Mars Fundamental Research Program
  • Acquisition of a FIB-SEM at the University of Arizona for the Analysis of Planetary Materials, NASA Planetary Major Equipment Program
  • Microstructural and Synthetic Studies of Calcium-Aluminum-Rich Inclusions: Insights into Early Nebular Chemistry, NASA Earth and Space Science Fellowship Program (D. Bolser)
  • Understanding Space Weathering of Asteroids and the Lunar Surface: Analysis of Experimental Analogs and Samples from the Haybabus and Apollo Missions, NASA Earth and Space Science Fellowship Program (M. Thompson)


OSIRIS-REx Collaborator


NASA ADS Author search: Thomas J. Zega


Bose, M., Zega, T. J., Williams, P. Assessment of alteration processes on circumstellar and interstellar grains in Queen Alexandra Range 97416 2014E&PSL.399..128B

Blinova, A. I., Zega, T. J., Herd, C. D. K., Stroud, R. M. Testing variations within the Tagish Lake meteorite—I: Mineralogy and petrology of pristine samples 2014M&PS...49..473B

Thompson, M. S., Zega, T. J. Determining the Oxidation State of Iron Nanoparticles in Mature Lunar Soil Through Electron Energy-Loss Spectroscopy 2014LPI....45.2834T

Zega, T. J., Haenecour, P., Floss, C., Stroud, R. M. Extraction and Analysis of Presolar Grains from the LAP 031117 CO3.0 Chondrite 2014LPI....45.2256Z

Thompson, M. S., Christoffersen, R., Zega, T. J., Keller, L. P. Nanoscale Analysis of Space-Weathering Features in Soils from Itokawa 2014LPI....45.2121T

Asaduzzaman, A. M., Zega, T. J., Runge, K., Muralidharan, K. Synthesis and Delivery of Amino Acids to the Early Earth via Surface Catalysis: A Computational Study 2014LPI....45.1647A

Miller, K. E., Thompson, M. S., Lauretta, D. S., Zega, T. J. Conditions for Formation of Chalcopyrite in the Rumuruti Chondrites 2014LPI....45.1461M

Haenecour, P., et al. Presolar Silicates as Tracers of the Formation of Fine-Grained Chondrule Rims in CO3 Chondrites 2014LPI....45.1316H

Zega, T. J., et al. A transmission electron microscopy study of presolar spinel 2014GeCoA.124..152Z

Bolser, D., Zega, T., Simon, S., Grossman, L. Analysis of Refractory Inclusions in the Allende and Axtell CV3 Chondrites via Electron-Backscatter Diffraction 2013M&PSA..76.5358B

de Gregorio, B. T., et al. Isotopic and chemical variation of organic nanoglobules in primitive meteorites 2013M&PS...48..904D

Asaduzzaman, A. M., et al. First Principles Investigation of Adsorption of Organic Molecules on Planetary Materials 2012M&PSA..75.5397A

Zega, T. J., et al. Measurement of the Oxidation State of Ti in Solar and Presolar Hibonite 2012LPI....43.2338Z

Zega, T., et al. Scanning Transmission X-Ray Microscopy on Calcium Aluminate From the Early Solar System And Ancient Stars 2011MiMic..17S1894Z

Boercker, J.E., et al. 2011 The Journal of Physical Chemistry Letters Size and temperature dependence of band-edge excitions in PbSe nanowires

Berger, E. L., et al. Evidence for aqueous activity on comet 81P/Wild 2 from sulfide mineral assemblages in Stardust samples and CI chondrites 2011GeCoA..75.3501B

Zega, T. J., et al. A Transmission Electron Microscopy Study of Presolar Hibonite 2011ApJ...730...83Z

Foos, E.E., et al. 2011 Journal of Materials Chemistry Synthesis of PbSe nanowires: the impact of the alkylphosphonic acid addition.

Tischler, J. G., et al. Band-edge excitons in PbSe nanocrystals and nanorods 2010PhRvB..82x5303T

Zega, T. J., et al. Mineral associations and character of isotopically anomalous organic material in the Tagish Lake carbonaceous chondrite 2010GeCoA..74.5966Z

De Gregorio, B. T., et al. Isotopic anomalies in organic nanoglobules from Comet 81P/Wild 2: Comparison to Murchison nanoglobules and isotopic anomalies induced in terrestrial organics by electron irradiation 2010GeCoA..74.4454D

Busemann, H., et al. Ultra-primitive interplanetary dust particles from the comet 26P/Grigg-Skjellerup dust stream collection 2009E&PSL.288...44B

Zolensky, M., et al. Comparing Wild 2 particles to chondrites and IDPs 2008M&PS...43..261Z

Leroux, H., et al. A TEM study of thermally modified comet 81P/Wild 2 dust particles by interactions with the aerogel matrix during the Stardust capture process 2008M&PS...43...97L

Baturina, O.A., Garsany, Y., Zega, T.J., Stroud, R.M., Schull, T., and Swider-Lyons, K.E., 2008 Journal of the Electrochemical Society Oxygen reduction reaction on Platinum/Tantalum oxide electrocatalysts for PEM fuel cells

Bassim, N. D., et al. Dislocations in III-nitride films grown on 4H-SiC mesas with and without surface steps 2007JCrGr.304..103B

Zega, T. J., et al. Coordinated isotopic and mineralogic analyses of planetary materials enabled by in situ lift-out with a focused ion beam scanning electron microscope 2007M&PS...42.1373Z

Zolensky, M. E., et al. Mineralogy and Petrology of Comet 81P/Wild 2 Nucleus Samples 2006Sci...314.1735Z

Brownlee, D., et al. Comet 81P/Wild 2 Under a Microscope 2006Sci...314.1711B

Zega, T. J., et al. Determination of Interface Atomic Structure and Its Impact on Spin Transport Using Z-Contrast Microscopy and Density-Functional Theory 2006PhRvL..96s6101Z

Zega, T. J., et al. Polyhedral serpentine grains in CM chondrites 2006M&PS...41..681Z

Garvie, L.A.J., Zega, T.J., Rez, P., and Buseck, P.R. 2004 American Mineralogist Nanometer-scale measurements of Fe3+/ΣFe by electron energy-loss spectroscopy: A cautionary note

Zega, T. J., et al. Serpentine nanotubes in the Mighei CM chondrite 2004E&PSL.223..141Z

Zega, T.J., Garvie, L.A.J., and Buseck, P.R. 2003 American Mineralogist Nanometer-scale measurements of iron oxidation states of cronstedtite from primitive meteorites

Zega, T. J., Buseck, P. R. Fine-grained-rim mineralogy of the Cold Bokkeveld CM chondrite 2003GeCoA..67.1711Z

Lauretta, D. S., Buseck, P. R., Zega, T. J. Opaque minerals in the matrix of the Bishunpur (LL3.1) chondrite: constraints on the chondrule formation environment 2001GeCoA..65.1337L

Zega, T. J., Buseck, P. R. Mineralogy of a Fine-Grained Rim Within the Cold Bokkeveld cm Chondrite: A Transmission Electron Microscope Study 2000M&PSA..35Q.177Z