Montana Tech Professor’s research could impact the way space explorers search for life on other planets

A Montana Tech professor’s research in Oman could hold important findings for future discovery of life on other planets. 
 
Dr. Alysia Cox traveled to an area on the Persian Gulf called the Samail Ophiolite, along with Dr. Alta Howells and other scientists from Arizona State University. The formation is part of a large slab of ancient seafloor that includes ultramafic rocks from Earth’s upper mantle. Ultramafic rocks have the lowest silica content of igneous rocks and are rich in minerals. When water reacts with the rocks, they form hydrogen gas in a process called “serpentinization.” Microorganisms then utilize hydrogen gas as an energy source. 
 
Cox and Howells are part of a team called the Group Exploring Organic Processes in Geochemistry led by Everett Shock of the Arizona State University School of Earth and Space Exploration and the School of Molecular Sciences. The results of the findings have been published in AGU’s JGR Biogeosciences, with Howells as the lead author and Cox as a co-author. 
 
The team, searching for the ways biodiversity might be impacted in serpentinization-hosted ecosystems, found that not all serpentinizing environments may support methanogens. The methanogens the researchers studied in the serpentinized fluids also required more energy than methanogens in freshwater and marine sediments. Methanogens are microorganisms that oxidize hydrogen gas with carbon dioxide to produce methane. The tiny life forms are believed to have evolved early on Earth. They are often found in serpentinization-hosted ecosystems.
 
If methanogens are not supported, organisms that reduce sulfate for energy may be more prevalent. 
 
“Because sulfate reducers don’t produce methane, this can have a big influence on the instrumentation we develop and deploy on missions to detect life on other planets,” Howells said.
 
The researchers haven’t yet determined the cause of their findings, but they think the high pH of the serpentinized fluids or the low availability of carbon dioxide, as the electron acceptor, might be responsible. 
 
“A requirement for energy is fundamental to all life on Earth,” Howells said. “If we can develop simple models with energy supply as a parameter to predict the occurrence and activity of life on Earth, we can deploy these models to study other ocean worlds.” 
 
“Dr. Howells did a great job making sense of a complex dataset to provide a framework for assessing where these microbes might be able to live. Her framework will be useful in studying similar environments on Earth and other ocean worlds. It was a pleasure to work with this team,” notes Cox.