Can we search for life on Mars without contaminating it?
December 09, 2025
Searching for life on other planets (and/or their moons) presents major challenges, including defining life in a way that doesn’t rely on what we know about Earth.
This NASA illustration shows what a Mars settlement might look like.
“When we go out looking for evidence of life, we do it set by the bounds of what we know of Earth life. For instance, there's no Earth life that can survive in really cold or really hot temperatures,” said Geology & Geophysics Professor Peter Doran. “So if we see those conditions, we think there can’t be anything living there. But those are Earth limits. Maybe on another planet some native organism exists that can live in really cold temperatures because it has a different chemical process for converting food into energy.”
Defining a concept of life is one of several questions scientists will tackle at AGU’s Town Hall on Expectations and Limitations in the Search for Life.
"The goal is to help the scientific community think about what it takes to look for life on Mars (and beyond), while considering related questions, such as how to avoid contaminating Mars with Earth life or bringing anything back that might be harmful," said LSU Geology & Geophysics Associate Professor Suniti Karunatillake.
This aligns with NASA’s current Moon to Mars program and the safeguards needed, Karunatillake said. The town hall further demonstrates LSU's leadership in the national discussion and connects to the university’s GANGOTRI project. Supported by the LSU Provost's Fund for Innovation in Research, the project is an effort to develop a Mars mission to investigate the geology and habitability of the planet's glaciers.
The question of how to explore Mars, and other planets, without contaminating them, is familiar to Doran, thanks to decades of work exploring Antarctic ecosystems without disturbing them. His experience is one of the reasons he was made vice chair of the Committee on Space’s Research’s Panel on Planetary Protection.
This international panel is deciding how best to explore other worlds without contaminating them with Earth microbes and confounding the search for life elsewhere.
LSU at AGU25
Join more than 250 LSU researchers at the premier Earth and space science conference and shape the future of our planet—the Annual American Geological Union (AGU) Meeting in New Orleans on December 15-19, 2025. Through visible, solutions-driven scholarship, LSU plays a leading role in shaping the conversations that matter at AGU.