The Ehlmann lab spans the options in Caltech’s Geological & Planetary Sciences Division.
As of January 2018, we are not actively seeking new graduate students or postdocs. But exceptional candidates for the Division postdoctoral fellowship programs or Caltech graduate studies should consider applying, especially if research interests span multiple faculty.
Professor Bethany Ehlmann
Professor of Planetary Science; Jet Propulsion Laboratory Research Scientist
Professor Ehlmann's research focuses on the mineralogy and chemistry of planetary surfaces, remote sensing techniques and instruments, astrobiology, and science policy and outreach.
Research Scientist in Image Processing
In his capacity as an imaging scientist in charge of Caltech's Bruce Murray Lab for Planetary Visualization, the Ehlmann group works extensively with Jay Dickson.
Dr. Rebecca Greenberger
Lab Manager and Research Scientist
Rebecca Greenberger received her PhD in 2015 from Brown University in Geological Sciences. She then joined the Ehlmann research group as a NASA Postdoctoral Program Fellow at JPL for two years and became the group’s lab manager and a research scientist at Caltech in July 2017. She is interested in the use of imaging spectroscopy and other spectroscopic techniques in the field and laboratory to better understand Earth and other planets.
Dr. Valerie Fox
Postdoctoral Scholar in Planetary Science
Valerie Fox is a postdoc studying smectite clays on Mars by measuring the spectral properties of laboratory analogs, and working with rover and orbital observations of clay-bearing Martian outcrops. She earned her PhD in Earth and Planetary Sciences from Washington University in St Louis, MO in 2017, and completed her bachelors degree in Physics at Carleton College, MN in 2012.
Dr. William Rapin
Postdoctoral Scholar in Planetary Science
William Rapin graduated in Planetary Science from Université de Toulouse III Paul Sabatier, Toulouse, France. His current research focuses on the identification of hydrated minerals at the surface of Mars and the geological implications of their finding. For this purpose he uses in situ data from the MSL/Curiosity rover, which he operates as part of the science team and lead on the ChemCam instrument.
Dana received a B.S. in Chemistry from the University of Michigan and continues to explore chemistry in different planetary science contexts as a Ph.D. candidate in Planetary Science at Caltech. In a recent project she analyzed laboratory data for the MSL ChemCam instrument to aid in the detection of salts on the surface of Mars. She also works with Prof. Geoff Blake on the chemistry of planet-forming regions.
Ellen completed an undergraduate degree in Earth Science at McGill University, then worked in the oil and gas industry for a couple of years before returning to academia. She works with visible-shortwave infrared reflectance spectroscopy, investigating the context of minerals identified on Mars (CRISM), as well as working with Earth analogues for Martian materials.
Peter Martin grew up in Gainesville, Florida and moved to Connecticut to attend Wesleyan University, where he double majored in Chemistry and Earth Science, graduating in 2010. He is now in his fourth year at Caltech as a geochemistry PhD student. His main research focuses are on applications of radiometric geochronology in planetary settings, although he is also more generally interested in planetary mission instrumentation and planning, which is the focus of his project with Prof. Ehlmann.
Sergio Parra is an Atlanta-native and earned his B.S. in Chemical and Biomolecular Engineering from the Georgia Institute of Technology, alongside a minor in Earth and Atmospheric Sciences. His current work centers on characterizing the aqueous alteration of carbonaceous chondrites using SWIR spectroscopy. His broad research interests include ancient habitable environments, the origin of life, and extant microbial communities in the deep biosphere.
Kevin Roback grew up in Michigan and got his bachelor’s in Earth and Environmental Science at the University of Michigan-Ann Arbor. He is interested in various sorts of planetary surface processes and currently studies active sand transport on Mars, as well as factors driving spatial patterns of landsliding on Mars.
Cecilia Sanders is a planetary science graduate student. She studies biosignatures - understanding how living things affect their environments, and how those effects might be recorded in the rock record, oceans, or atmosphere of a planet. She does this by culturing microbes in the lab and by going out in the world to understand paleoenvironments and biosignatures in the deep history of the Earth, interrogating samples from all these sources using Caltech’s incredible suite of analytical instruments. In addition to her research, Cecilia is an avid artist/illustrator and volunteers her time teaching elementary school science classes.
Eva Scheller got her B.Sc. in geology-geoscience from University of Copenhagen. Her current projects include composition and impact deformation of Noachian basement on Mars and formation of ikaite and dendritic textures in tufa in alkaline lakes. Her research interests include Martian geology, paleoclimatology, ancient habitable environments, and low-temperature geochemistry.
Nathan Stein graduated from Washington University in St. Louis in 2015 where he studied physics and geophysics. Broadly, he is interested in remote sensing and planetary surface processes. He works with Prof. Ehlmann on the Dawn mission studying the formation of bright spots on Ceres.
Nancy Thomas is a fourth year Ph.D. Candidate in Planetary Science. She majored in Physics and Astronomy and minored in Mathematics and Earth & Space Sciences at the University of Washington. Her research focuses on characterizing salts and diagenesis using ChemCam data from MSL Curiosity and identifying martian surface mineralogy using quantitative, automated techniques for CRISM.
- Dr. Elena Amador (postdoc 2017-2019) –now Systems Engineer on MSL Science Operations Team at JPL
- Dr. Peter Buhler (PhD 2018) –now NASA Postdoctoral Program Fellow at JPL
- Dr. Jennifer Buz (PhD 2018) –now Postdoctoral Researcher, Northern Arizona University
- Dr. Daven Quinn (PhD 2018) –now Postdoctoral Scholar, University of Wisconsin-Madison
- Dr. Mathieu Lapôtre (PhD 2017) –now John Harvard Distinguished Science Fellow at Harvard University
- Dr. Lu Pan (PhD 2017) –now Marie Curie Fellow at Université Claude Bernard Lyon, France
- Dr. Abigail Fraeman (postdoc 2014-2016) –now Research Scientist at JPL
- Dr. Christopher Edwards (postdoc 2012-2015) –now Assistant Professor at Northern Arizona University
- Dr. Cedric Pilorget (postdoc 2012-2014) –now Maître de conferences at Univ Paris-Sud
Current and Former Summer Interns
- Ethan Ordentlich (Caltech ’21; co-advised with Rebecca Greenberger)
- Lauren Suezaki (Caltech ’21)
- Elise Cutts (Caltech ’19)
- Geraint Northwood-Smith (Cambridge ’17; co-advised with Abigail Fraeman)
- Caue Borlina (U. Michigan ’16; now graduate student at MIT, planetary sciences)
- Eyjolfur Gundmundsson (U. Reykjavik ’13; now graduate student at U Chicago, medical physics)
- Bryne Hadnott (WUSTL ’13; now graduate student at Cornell, geological sciences)
- Cecilia Sanders (Harvard ’16; now graduate student at Caltech, planetary science; co-advised with Glenn Sellar (JPL))
- David Smith (Troy High School, ’13)
- Jade Wang (Caltech ’15)