What does it mean to be alive? Could life exist elsewhere in the universe, and if so, how would we recognize it?
On Jan. 14, 2025, Dr. Michael L. Wong, Postdoctoral Fellow at Carnegie Science’s Earth & Planets Laboratory, addressed these mysteries during a seminar at the Trottier Space Institute (TSI) at McGill. Wong’s talk, titled Pondering Our Place in the Universe, showcased his interdisciplinary approach, blending planetary science, data science, and philosophy.
Wong began his presentation by framing the core questions of astrobiology: How does life emerge? And what makes a planet habitable? These questions, he argued, demand a multidimensional approach to better understand life’s inherent complexity.
Earth’s distinct atmosphere
One of the key focuses of Wong’s research is atmospheric chemistry. Earth’s atmospheric network is distinct from those of other planets. This could be because Earth’s atmosphere reflects a combination of its biosphere and technosphere—the part of the environment made up or modified by humans. Together, these two unique features form a technobiosphere.
“Earth’s atmospheric network is the most non-random network we’ve observed,” Wong noted.
This means that although everything in the universe is formed randomly, our atmosphere has the most non-random biochemistry that would be conducive to harbouring life.
This begs the question: Does life reorganize matter in a universal manner? And if so, it raises intriguing possibilities for identifying biosignatures—chemical traces of life—in the atmospheres of exoplanets.
How do we detect life?
The next part of Wong’s talk focused on methods to detect life beyond Earth. One method is the use of Pyrolysis Gas Chromatography-Mass Spectrometry (Pyrolysis GCMS), which uses heat to separate the chemical components of a sample to then analyze it. This approach, Wong explained, offers several advantages: Minimal sample preparation, versatility in extreme environments, and low energy requirements.
“If there is life on an alien world, it will not exhibit the exact same biochemistry as Earth,” Wong emphasized.
By training machine learning algorithms on a diverse range of biotic and abiotic samples, Wong’s team achieved an impressive 90 per cent accuracy rate in determining whether a sample contained evidence of life. However, challenges remain, particularly when identifying fossilized life or life concealed within mixtures of abiotic components.
Ethics of the Cosmos
Wong advocates for the development of astrobioethics, an ethical framework to guide humanity’s exploration of outer space. With private companies, such as SpaceX, accelerating the path to space travel, Wong urged the audience to consider what constitutes moral value in the cosmos.
“We have an obligation to respect that which is morally valuable,” Wong explained. “The big question is, what actually constitutes moral value in outer space?”
Should intrinsic value be assigned only to living entities, or do non-living structures with innate complexity deserve moral consideration? These questions are crucial to answer as humans prepare to venture into extraterrestrial environments.
Looking to the Future
From missions like NASA’s Europa Clipper and Dragonfly to the potential for sample-return missions from Mars and Enceladus, Wong highlighted the exciting opportunities that lie ahead.
“These missions could revolutionize our understanding of life in the universe,” he said.
Moving forward, Wong hopes to partner with space agencies to continue searching for signs of life in the cosmos. He also aims to bring more attention to the field of astrobioethics to fuel moral discussions on space exploration and interaction with the universe.
Wong’s seminar offered a thought-provoking mix of innovative science and deep philosophical reflection. By pushing the boundaries of planetary science and ethics, he is paving the way for humanity’s search for life beyond Earth.
“Astrobiology doesn’t just answer questions about life elsewhere,” Wong concluded. “It helps us better understand what it means to be alive here.”
