SwRI receives $3 million NASA astrobiology grant to study microbial life in Alaska’s arctic sand dunes

(Press-News.org) SAN ANTONIO — March 11, 2025 —Southwest Research Institute (SwRI) has received a three-year, $2,999,998 million grant from NASA to identify and characterize life and its biosignatures in frozen sand dunes in Alaska, under conditions similar to dune fields on early Mars and Saturn’s moon Titan. The Assessing Regional Reflectors of Astrobiology in Kobuk dunes for Interplanetary Science (ARRAKIS) project team, which includes researchers from Brigham Young University and the University of California—Davis, seek insight into how microbial life may thrive in extreme environments on other worlds by understanding the limits on and constraints affecting life in similar planetary analog environments on Earth.

“Basaltic and gypsum sand dunes on Mars and hydrocarbon sand dunes on Titan experience freezing temperatures. Understanding how frozen sands in Earth’s Arctic interact with and support microbial life can help us learn how to search for life in similar frozen conditions elsewhere in the solar system,” said SwRI Staff Scientist Dr. Cynthia Dinwiddie, the principal investigator of the project.

The researchers plan to study the Great Kobuk Sand Dunes in Alaska’s Kobuk Valley National Park to understand the lifeforms living in nutrient-poor sand dunes subject to extreme conditions typical of the Arctic. The 25 square miles of dunes freeze annually at their surface and may include a core of dry permafrost — sand with little or no moisture that remains frozen during the warm season.

“We’ve seen water perched in the near surface of the tallest dunes in Kobuk Valley,” Dinwiddie said. “Perched water occurs when an impermeable layer traps water above it, creating a separate reservoir perched above the regional groundwater aquifer. Water is essential to life on Earth, so SwRI is targeting this perched liquid water for several types of astrobiological analyses.

Water may be perched on an impermeable layer consisting of ice, carbonates or fine-grained material like clay, each of which may accumulate at the base of the actively freezing and thawing layer. Approximately 7% of this dune sand consists of carbonate grains, and exhumed carbonate layers have been observed on the surface of the low-lying areas between dunes.

The researchers will locate these deep, nutrient-poor but wet zones in the frozen sand dunes using near-surface geophysics and biogeophysics methods to pinpoint their depth-dependent search for life. The team will conduct research at the Great Kobuk Sand Dunes twice in 2025, both in the month of March and again in late summer, to observe how the changing seasons affect the activity levels of microbes living deep beneath the surface.

To accomplish this, the researchers will use Raman spectroscopy, which identifies covalently bonded compounds via a laser with a single wavelength of light. The portable instrument Astronaut Raman for In situ resource utilization and Astrobiology (ARIA), developed by SwRI’s Dr. Charity Phillips-Lander, uses Raman spectroscopy to examine the mineralogy of samples and identify organic compounds present. This technique helps determine the composition of samples and the presence of certain materials based on how the light wavelength shifts after interacting with a substance.

SwRI will also use gas chromatography/mass spectrometry (GC/MS) to identify and quantify organic compounds within samples from the dunes, and analytical techniques to measure the concentration of adenosine triphosphate (ATP) and total DNA. Because ATP is present in all living organisms, its measurement can be used to assess cellular activity. Total DNA can be used as a rough proxy for biomass.

Life-detection space science missions will require multiple types of measurements like those the ARRAKIS team are using to provide confidence that a detected signal is related to present or past life. By performing these measurements on samples gathered from analogous environments on Earth, the team will provide critical insight into how to look for life in the subsurface of other planets and moons in our solar system, which will benefit future missions like the potential Mars Life Explorer mission that was prioritized in the most recent Planetary Science and Astrobiology Decadal Survey.

“While we don’t know much about lifeforms thriving deep inside frozen sand dunes, perched liquid water located high in these dunes that does not seasonally freeze provides a potential oasis for life in an arctic desert and could help us make useful inferences elsewhere,” Dinwiddie said. “Life finds a way, even in seemingly inhospitable places.”

For more information, visit https://www.swri.org/markets/earth-space/earth-science.

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