Meet the Lab

Our team members come from institutions in the LA area, out of state, and even internationally. Some come in as undergraduate or graduate student interns and work for a summer up to several years. Some team members are mentor funded; some come in with their own funding through fellowships, student awards, or external grants. Some work with us as visiting researchers or remotely. We also regularly collaborate with many excellent researchers and colleagues both from inside JPL and from institutions around the world.

Students, Postdocs, Visiting Researchers

Dennise Valadez

Dennise is currently pursuing her MS in Physics from CSU Los Angeles. She has a BS in Physics and Chicano/a studies from UCLA. Her research interests include the search for life outside of Earth as well as better understanding the origins of life here on Earth. She is working with the OHL on investigating chemical pathways in ocean world analog systems to resolve possible indicators of abiotic organic chemistry and habitability on Ceres and Enceladus.

Julia Chavez

Julia is working on her Master's in Environmental Engineering at CSU Los Angeles. She has a Bachelor’s in Mathematics from Lewis & Clark College. She is working with the OHL to simulate hydrothermal vents in the lab. In particular, she will study saponite precipitates: their use in carbon dioxide sequestration and their relevance to habitable environments on early Earth and early Mars.

Nancy Carman

Nancy is a Geosciences PhD student at the University of Nevada, Las Vegas. She works on determining the degree of diagenesis on Mars, specifically looking at if there are S-containing organic minerals from Vera Rubin Ridge and Glen Torridon, mainly focusing on Mn sulfides. She will be working with the OHL to simulate the growth of hydrothermal chimneys with conditions analogous to the Strytan hydrothermal field in Iceland, an analog to hydrothermal environments on early Mars.

Meghan Winzler

Meghan is a Microbiology undergraduate student at CSU Long Beach. Meghan is working with the OHL to characterize geological samples from hypersaline brines through the isolation and extraction of DNA, RNA, and proteins. These brine samples are from mineral-brine field sites that range in age from modern/surface settings to geologically old samples dated to be ~253 Myr and are of great interest as homologs to the Martian hypersaline evaporite mineral environment.

Paulina Cortez

Paulina is a STEM Teacher and Researcher (STAR) Program fellow with a Bachelor's degree in Biology and Spanish from San Diego State University and just recently graduated with her Bilingual Single Subject Teaching Credential in Biological Sciences also from SDSU. Through her STAR project, “What Does It Take To Make A Biosignature?”, she will assess the gene expressions of in-situ samples from hypersaline brine sites and their associated DNA, RNA, and protein profiles from preserved microbial community sources.

Jose Valera

Jose is starting a PhD in microbiology (Fall 2021); his main goal is to investigate and understand specific extreme microorganisms ("extremophiles'') that inhabit planetary analogue environments such as hypersaline lakes and hot springs. He is working with the OHL to use these studies to bridge gaps between observational biosignatures and microbiological exchanges in the environment.

Devan Nissan

Devan is a geosciences Ph.D. candidate in the Onstott Lab at Princeton University. She is working with the OHL to investigate the unique abiotic/prebiotic geochemical signatures of a hypersaline brine in the deep subsurface of South Africa’s Witwatersrand Basin.

Laura Rodriguez

Laura Rodriguez earned her B.S. in Geochemistry at Rice University before obtaining her Ph.D. in Geosciences and Astrobiology at Penn State. Laura is working on hydrothermal vent geochemistry, phosphorus chemistry in planetary systems, and is part of the INVADER vent exploration project.

Erika Flores

Erika is completing her Master's degree in Environmental Engineering at CSU Los Angeles, and has a Bachelor's in Chemical Engineering from Cal Poly Pomona. She is working on prebiotic organic synthesis and phosphorus absorption in hydrothermal systems.
(Image credit: NASA/JPL-Caltech/Kim Orr)

Preston Tasoff

Preston is a microbiology undergraduate student at Washington University, St. Louis. He is working with us on validating and measuring DNA preserved in extreme environments, and studying biomarker preservation in harsh UV environments.

Eduardo Martinez

Eduardo is a Master’s student in Civil Engineering at Cal State LA. He is working with us on making simulated hydrothermal vent chimneys in the lab, and studying how organics affect iron oxide / hydroxide and silica precipitation.

Erika Flores

Jessica Weber earned her Ph.D. in Chemistry from MIT and a B.S. in Chemistry from U of Chicago. Jessica is a JPL Postdoctoral Researcher exploring how protein cofactors behave under early Earth conditions.

Chhandak Basu

Dr. Chhandak Basu is a Professor of Biology at California State University, Northridge. His research focuses on understanding the molecular, biological, and genomic aspects of abiotic stress tolerance mechanisms in microbes and plants in extreme environments. Dr. Basu currently collaborates with the OHL on astrobiology research, particularly studying gene expression patterns in extremophile microbes collected from planetary analog field sites.

Rachel Sheppard

Rachel completed her BA in Earth Science at Columbia University studying organic molecules in fault rocks and completed her PhD in Earth & Planetary Science at Brown University studying how water-bearing minerals record aqueous conditions on Earth and Mars. She is a postdoc working on redox gradients in the martian subsurface, and is a member of the MSL science team.

Theresa (Tess) Marlin

Tess is a second year biology Ph.D. student at Caltech. She studies the origin of metabolism, particularly reactions of simple organic molecules with minerals in ocean world analog environments, and is interested in possible metabolisms that might exist on ocean worlds.


Keith Chin

Keith is a JPL Technologist in the JPL Electrochemical Technologies group. His research focuses on the development and infusion of energy storage, energy generation, and in-situ electrochemical instrumentation (development, modeling, and prototyping) technologies for a broad range of autonomous spacecraft systems. Keith frequently collaborates with OHL researchers on astrobiology projects, particularly on development of electrochemical in-situ instruments for monitoring planetary environments.

John-Paul Jones

John-Paul is a JPL Technologist in the Electrochemical Technologies group. His research focuses on lithium metal batteries, lithium sulfur batteries and fuel cells for extreme environments, with an overall focus on energy storage and conversion. John-Paul frequently collaborates with the OHL on astrobiology research particularly in the area of adapting fuel cell technology to simulate planetary habitability and energy for redox metabolism in ocean world systems.


Medha Prakash

Medha is pursuing a BS in Environmental Sciences at the University of Virginia. She worked with the OHL on carbon reduction reactions in planetary environments, relating to understanding methane on Mars and prebiotic chemistry in early Earth settings.

Sarah Lamm

Sarah worked with the OHL on deconvoluting the geochemical signatures of metastable minerals relevant for life in Mars and ocean floor environments using LIBS and Raman. She is currently a PhD student in Geology at Kansas University.

Jonathan Major

Jonathan worked with us for his M.S. degree on simulating phosphorus chemistry in iron and manganese mineral systems on Mars and ocean worlds, and evaluating habitability in redox active systems. He is currently a Ph.D. student in the Pasek lab at University of South Florida.

Ninos Hermis

Ninos worked with us on simulating temperature gradients and electrical properties in hydrothermal vents, and on studying electrochemistry of ocean world analog minerals. He is currently a Ph.D. student in the Braun lab at Ludwig Maximilian University of Munich.

Michelle Hooks

Michelle (STEM Teacher and Researcher fellow; Biology and Education, USC) worked with us on the effects of organic molecules on iron-silicate and iron-hydroxide chemical garden systems, with applications for origin of life and looking for biosignatures on other worlds. She is now working at NASA Johnson Space Center.

Hiroki Nishimura

Hiroki is completing his degree in Marine Science at Tokyo University of Marine Science and Technology (TUMSAT). He was a visiting researcher in our lab under the Japan Public-Private Partnership Student Study Abroad Program, and continues to work with us on the effect of amino acids on phosphorus adsorption on iron minerals in ocean systems.

Sarah Crucilla

Sarah (geology, Caltech) worked with us on testing how protein cofactors behave in early Earth conditions, and studying how extremophiles live in radiation-intensive environments. She is currently a research assistant at Harvard.

Jemma Dickson

Jemma (chemistry and marine science, College of the Atlantic) worked with us on incorporating microbes into hydrothermal chimney experiments under the Maine Space Grant program.

Jason Pagano

Dr. Jason Pagano is a professor of Chemistry at Saginaw Valley State University in Michigan specializing in silicate chemical garden systems. He conducted his 2018-2019 sabbatical at JPL with our team, working on chemical gardens of iron hydroxide and iron silicate, and the effects of organics on precipitation.