From Earth to Mars and back again

How the research of LANL postdoc Debarati Das impacts the understanding of Mars geology and renewable energy

There is an ironic orbit to Debarati Das’ work and how she arrived at Los Alamos National Laboratory. Das is a Chick Keller Postdoctoral Fellow in Space Remote Sensing & Data Science. Starting as a geologist, her current work focuses on the geology and the chemical makeup of Mars, but it has direct implications for renewable energy on Earth.

From Earth to space

Das started her scientific journey in India, where she began her career as a geologist studying the Himalayas. Then she had an opportunity to study meteorites in Japan.

“That was the transition for me,” she said. “I got a taste of what space science looks like and it was exciting.”

Das pivoted from her mountainous past to a second master’s degree at McGill University in Montreal, Quebec, angling her sights toward the stars as she studied meteorites. When a professor asked what her next career step was, her answer was simple: “Anything to do with space.” That conversation steered her down the path of Mars science for her doctorate, which included a project with her faculty advisor and the NASA Mars Science Laboratory team.

“While establishing my project, I was doing research and the first thing I googled was ‘what is the coolest thing on Mars right now?’” Das said with a laugh. “What showed up was that boron had been recently discovered in a crater on Mars.”?

She told her advisor about the work, who informed her that the researcher who made the discovery, Patrick Gasda, worked for Los Alamos National Laboratory. Excited, Das called Gasda to discuss how she might be able to contribute. Her timing was perfect: Gasda was a new staff member and was looking for collaborators to help advance the work. He became Das’ mentor on a new project studying Martian brines, salty groundwater that could have provided the raw ingredients for life.

“Throughout my doctorate, I was mentored by really excellent scientists at Los Alamos,” Das explained, adding that Gasda and his team trained her to interpret Mars data and to build collaborations. As she completed her doctorate, pursuing a postdoc at the Laboratory seemed a natural fit for her background and experience. “And that is how I went from being a geologist in India to working in space science in New Mexico.”

In orbit

Now at Los Alamos and deep in space science, Das is working on determining past water activity in Gale crater by studying highly water-mobile elements. She is using data provided by the Curiosity rover’s ChemCam instrument (the laser instrument at the head of the rover) that analyzes the elemental composition of rocks on Mars.

“It’s like looking at snapshots from a time when life was just forming on Earth,” Das said. “It’s something I feel very privileged to do. This is data that is telling me the history of a different planet that we’ve never been to. That blows my mind.:

While there is currently no surface water on Mars, liquid water used to be abundant based on a wealth of landforms, like streambeds, and the presence of both hydrated minerals (containing water in their structure) and “salty” minerals (forming after water evaporates).?

As Das explains, observing water soluble materials and minerals that require water to form is exciting because “that give us an insight on where life could have been possible” on Mars. By homing in on water soluble materials, the team is getting a high-resolution understanding about water on Mars in the last moments before it evaporated and how that impacted the topography of the red planet.

Das and the Space and Planetary Exploration team are specifically looking for boron and lithium. Boron is hypothesized to have helped jump-start life on Earth by catalyzing the reaction that turns organic elements — oxygen, carbon, nitrogen, and hydrogen — into organic molecules like RNA and DNA.

The Curiosity rover is currently traversing a Martian area with an increased presence of salty minerals called “evaporites." So far, only veins of evaporites have been encountered by the rover. The higher abundance of these minerals points to the existence of habitable environments on Mars, where there could have been life. This makes this region particularly exciting for Das and her colleagues, and Das feels sure that there are many discoveries waiting to be made in these salty rocks.

Returning to land

Closing the circle of Das’ journey, the future of the project also brings it back to Earth and renewable energy. The second element that the team identified on Mars was lithium, which is necessary for clean energy applications reliant on lithium batteries, such as electric cars.

“We don’t really know as much as we’d like to know about lithium,” Das said. “Especially how it enriches underground in hydrothermal brines.”

Lithium is predominantly mined out of hard rocks or extracted out of brines in dry lakes, a process that generates significant greenhouse gases with a relatively high carbon dioxide footprint. With exponential growth anticipated in the lithium market, it’s important to understand how lithium extraction can be optimized to reduce its carbon footprint and limit water-heavy mining that burdens dry-lake localities.

To better understand lithium and boron enrichment, Das uses theoretical models to map the behavior of lithium and boron in ancient evaporative environments in Gale crater.? She hopes to further model lithium enrichment in terrestrial geothermal settings by collaborating with the Earth and Environmental Sciences division at Los Alamos, as well as with the NASA Mars Science Laboratory.

The shift towards eco-friendly energy resources that involve highly water-mobile elements on Earth inspires further research on lithium and boron enrichment processes in Gale crater on Mars. This research will not only help expand the understanding of past aqueous activity on Mars but also has important applications for a greener future on Earth.

“We might not be able to send humans to Mars yet and we also don’t have easy access to the deep underground on Earth, however even with the data we are collecting using the Curiosity rover on the surface of Mars, we may unlock information about elements that are key for a sustainable future on Earth,” said Das.

Debarati Das is mentored by Patrick Gasda, Nina Lanza and Sam Clegg.

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