Traces of life detected in Finnish crater shed light on origins of life on Earth

Traces of life detected in Finnish crater shed light on origins of life on Earth
by Jeff Renaud
London, Canada (SPX) Sep 25, 2025

An international team of scientists, including Western University's Gordon Osinski, has for the first time dated the emergence of microorganisms inside a meteorite crater, demonstrating that life developed within millions of years after the impact event.

The discovery was made in Finland's 78-million-year-old Lappajarvi crater and provides direct evidence that meteorite impacts can generate habitable environments, both on Earth and potentially on other planets.

"This is incredibly exciting research as it truly connects the dots for establishing life on Earth for the first time," said Osinski, an Earth sciences professor and study co-author. "Previously, we've found evidence that microbes colonized impact craters, but there have always been questions about when this occurred and if it was due to the impact of the meteorite, or some other process millions of years later. Now we have evidence that this impact event created a warm, wet habitable environment right after it formed, which was soon colonized by microorganisms."

Osinski collaborated with international colleagues in Finland, assisting in sampling and geological analysis of drill cores from the Lappajarvi site.

Henrik Drake, professor at Linnaeus University in Sweden and senior author of the study, noted, "This is the first time we can directly link microbial activity to a meteorite impact using geochronological methods. It shows that such craters can serve as lifelong habitats in the aftermath of the impact."

By using isotopic analyses of mineral deposits in fractures and cavities, the team determined that microbial colonization began only a few million years after the crater formed, within a hydrothermal system at roughly 47oC. These conditions supported microbial sulfate reduction, a process essential to subsurface ecosystems, confirming that microorganisms thrived in the impact-generated environment.

Further analysis revealed mineral deposits formed more than 10 million years later, bearing signatures of methane production and consumption, indicating long-lasting microbial activity.

"What is most exciting is that we do not only see signs of life, but we can pinpoint exactly when it happened. This gives us a timeline for how life finds a way after a catastrophic event," said Jacob Gustafsson, PhD student at Linnaeus University and first author of the study.

Research Report:Deep microbial colonization during impact-generated hydrothermal circulation at the Lappajarvi impact structure, Finland