The Ehlmann lab spans the options in Caltech’s Geological & Planetary Sciences Division.

Interested in joining the Ehlmann lab?

  • We are not actively seeking new personnel right now. We keep a moderate size so that each person gets the attention they need.
  • Postdoctoral scholars: See opportunities across the GPS Division here.
  • Graduate students: Graduate students apply in December to a GPS Division Ph.D. option and work with two faculty their first year prior to selection of an advisor(s) (see GPS graduate program FAQ). We are not presently in active recruiting mode but do review all applications received and make option-level admissions decisions in conjunction with other faculty.
  • Undergraduate students: For those Caltech or PCC students interested in lunar science or mission operations, we have a Lunar Trailblazer internship, offered termly (announced on the mission twitter). Caltech has WAVE/SURF programs for summer interns but the Ehlmann lab is not taking students in 2024.


Bethany Ehlmann

Professor Bethany Ehlmann
Professor of Planetary Science
Professor Ehlmann's research focuses on the mineralogy and chemistry of planetary surfaces, remote sensing techniques and instruments, astrobiology, and science policy and outreach.
Biography >>


Rebecca Greenberger

Dr. Rebecca Greenberger
Lab Manager and Research Scientist
Dr. Rebecca Greenberger (she/her/hers) received her PhD in 2015 from Brown University, joined the Ehlmann group as a NASA Postdoctoral Program Fellow at JPL for two years, and has been the group’s lab manager and a research scientist at Caltech since 2017. She is interested using imaging spectroscopy and other spectroscopic techniques in the field and laboratory to better understand Earth and other planets. Her current projects include investigation of deep hydrothermal circulation in Earth's ocean crust and the products of serpentinization, both using micro-imaging spectroscopy.

Jasper Miura

Jasper Miura
Mission Research & Communications Specialist
Jasper Miura (he/him) joined the Ehlmann lab after completing his B.Sc. in inorganic geochemistry at Brown University in 2019. His current project uses imaging spectroscopy to study Martian meteorite spectral diversity. His work also consists of brand design, web design, and general graphic design for the Lunar Trailblazer mission.

Graduate Students

Samantha Baker

Samantha Baker
Graduate Student
Samantha Baker (she/her/hers) graduated from the University of Chicago in 2021 with a B.S. in Geophysical Sciences. In her current research, she uses spectral data to understand the aqueous history of Mars through the examination of silicate weathering. Her broad research interests include exploring planetary surface processes through the lenses of geochemistry and geomorphology.

Mma Ikwut-Ukwa

Mma Ikwut-Ukwa
Graduate Student
Mma Ikwut-Ukwa (she/her) received her A.B. in Astrophysics with a secondary in Earth and Planetary Sciences from Harvard University in 2020. Mma’s interests span questions of evolution and habitability for solar and extrasolar planets. She is currently working on dating glacial-like features in the Martian mid-latitudes to provide constraints for models of the Amazonian climate.

Valeria Kachmar

Valeria Kachmar
Graduate Student
Valeria Kachmar (she/her) graduated with a B.Sc. in Physics from RUDN University, Russia, in 2021. Before joining the Ehlmann lab in 2022, she worked on microwave experiments to simulate the lunar dust exosphere in the lab. Currently, she is modeling reflectance spectra of water-ice deposits on the Moon, trying to understand how different ice scenarios would manifest themselves in remote sensing data.

Oak Kanine

Oak Kanine
Graduate Student
Oak (they/them/theirs) graduated from Dartmouth College in [the fateful year of] 2020 with A.B.s in Earth Science and Native American Studies. Their broad research interests include Martian paleoclimate; the development of a generalized model of planetary evolution through comparative planetary science; and questions of habitability. Their current work focuses on Martian geomorphology and the history of liquid water on Mars, as well as Martian landscape evolution through dry processes such as rockfall.

Samantha Baker

Abigail Keebler
Graduate Student
Abigail Keebler grew up in southeastern Pennsylvania and graduated from West Chester University of Pennsylvania in 2021 with her B.S. in Geoscience-Geology and minors in Physics and Mathematics. Abigail is interested in planetary surface processes on terrestrial planets and rocky moons. Currently, she is using spectroscopy to constrain the mineralogy of atmospheric dust on Earth.

William Lawrence

William Lawrence
Graduate Student
Will Lawrence is from Toronto, Canada and graduated from Yale in 2022 with a B.Sc. in Chemistry and Earth & Planetary Sciences. His current research involves the spectral characterization of primitive meteorites (carbonaceous chondrites) and how it may be used to elucidate processes that occurred on parent body asteroids. He is generally interested in the application of remote sensing to space exploration, as well as the distribution and evolution of organic matter and volatile compounds in the solar system.

Jessica Mueller

Jessica Mueller
Graduate Student
Jessica grew up in Nampa, Idaho, and graduated from Boise State University with a B.S. in Geosciences in 2021. She is broadly interested in the isotopic and mineral evolution of the solar system. In her current research, she is creating a robust framework of spectral data from calcium-aluminum-rich inclusions (CAIs) that will better inform the interpretations of remote sensing data.

Sergio Parra

Sergio Parra
Graduate Student
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.

Yu Yu Phua

Yu Yu Phua
Graduate Student
Yu Yu Phua graduated from the University of Tokyo in 2021 with a M.S. in Materials Science. She is interested in studying planetary chemistry involving H2O through laboratory experiments. Currently, she is working on the detection threshold for H2O spectral signatures.

Erin Pimentel

Erin Pimentel
Graduate Student
Erin Pimentel (she/her) graduated from Hamilton College in 2022 with a B.A. in Geosciences and minors in Mathematics and Japanese. She is broadly interested in planetary surfaces and the remote sensing techniques used to study them. She is currently working on improving topography maps over tessera terrain on Venus using Magellan radar altimeter data and integrating datasets of water ice abundance on the Moon in preparation for the upcoming Lunar Trailblazer mission.


  • Dr. Andrew Annex (postdoc 2022-2024) -now Research Scientist at SETI
  • Dr. Lucia Mandon (postdoc 2022-2023) -now Postdoc at Institut de Planétologie et d'Astrophysique de Grenoble
  • Dr. Eva Scheller (PhD 2022) –now 51 Pegasi b Postdoctoral Fellow at MIT
  • Dr. Kevin Roback (PhD 2021) –now Research Staff Member, Institute for Defense Analyses
  • Brandon Rasmussen (MS 2020) –now researcher at Planet
  • Dr. Nathan Stein (PhD 2020) –now Senior Machine Learning Engineer, Epirus
  • Dr. Ellen Leask (PhD 2020) –now Postdoctoral Scholar, Applied Physics Lab
  • Dr. William Rapin (postdoc 2017-2020) –now CNRS Research Scientist, Université de Toulouse
  • Dr. Peter Martin (PhD 2020) –now Associate Data Scientist II, KoBold Metals
  • Dr. Dana Anderson (PhD 2020) –now Postdoctoral Fellow, Carnegie Science
  • Dr. Valerie Fox (postdoc 2017-2019) –now Postdoctoral Researcher, University of Minnesota
  • Dr. Nancy Thomas (PhD 2019) –now Director, Image Processing and Software, BlackSky
  • Dr. Elena Amador (postdoc 2017-2019) –now Systems Engineer on MSL Science Operations Team at JPL
  • Dr. Peter Buhler (PhD 2018) –now Research Scientist, Planetary Science Institute
  • Dr. Jennifer Buz (PhD 2018) –now Principal Remote Sensing Scientist, Orbital Sidekick
  • Dr. Daven Quinn (PhD 2018) –now Research Scientist, University of Wisconsin-Madison
  • Dr. Mathieu Lapôtre (PhD 2017) –now Assistant Professor at Stanford University
  • Dr. Lu Pan (PhD 2017) –now Assistant Professor of Planetary Science, University of Science and Technology of China
  • Dr. Abigail Fraeman (postdoc 2014-2016) –now Research Scientist at JPL
  • Dr. Christopher Edwards (postdoc 2012-2015) –now Associate Professor at Northern Arizona University
  • Dr. Cedric Pilorget (postdoc 2012-2014) –now Research Faculty at IAS-Orsay

Current and Former Interns

  • Rory Knight (MIT ’24; co-advised with Rebecca Greenberger)
  • César León Jr. (Columbia University ’24; co-advised with Rebecca Greenberger)
  • Kenzie Mounir (Washington University in St. Louis ’25; co-advised with Rebecca Greenberger)
  • Belinda Blakley (Pasadena City College)
  • Claire Blaske (Arizona State University ’23; co-advised with Rebecca Greenberger; now graduate student at Stanford University)
  • Amy Wang (Cornell ’23; co-advised with Rebecca Greenberger)
  • Sahil Azad (Caltech ’25; co-advised with Rebecca Greenberger)
  • Andy Sun (Caltech ’24)
  • Riley Tam (Caltech ’24; co-advised with Jay Dickson)
  • Marcos Perez (Caltech ’23)
  • Molly Crotteau (Caltech ’21; co-advised with Rebecca Greenberger; now graduate student at UC Santa Barbara)
  • Ethan Ordentlich (Caltech ’21; co-advised with Rebecca Greenberger)
  • Lauren Suezaki (Caltech ’21, now electrical engineer at Northrop Grumman)
  • Elise Cutts (Caltech ’19; now American Association for the Advancement of Science Mass Media Fellow)
  • Geraint Northwood-Smith (Cambridge ’17; co-advised with Abigail Fraeman; now graduate student at Imperial College London, planetary science)
  • Cauê Borlina (U. Michigan ’16; now Postdoctoral Fellow at Johns Hopkins University)
  • Eyjolfur Gudmundsson (U. Reykjavik ’13; now research fellow at University College London, medical image computing)
  • Bryne Hadnott (Washington University in St. Louis ’13; now Data Curator and Storyteller at Stanford University)
  • Cecilia Sanders (Harvard ’16; co-advised with Glenn Sellar (JPL); now Postdoctoral Fellow at Johns Hopkins University)
  • David Smith (Troy High School, ’13)
  • Jade Wang (Caltech ’15)