Scientists find evidence of microbes survived long after asteroid hit in Finland

Evidence of microbes survived long after asteroid hit in Finland (Image: Robert Lea /NASA/JAXA/University of Tokyo)

Around 78 million years ago, a massive asteroid struck Earth. The impact formed a 23‑kilometre wide crater in Lake Lappajärvi, Finland. Temperatures soared to roughly 2,000 °C, initially sterilising surrounding rock completely.

Microbial Life Emerges

Despite extreme heat, microbes colonised fracture-filled rocks beneath the crater. Geological evidence indicates life returned within four million years. Mineral veins and crystal formations preserve signatures of microbial activity.

Researchers from the University of Helsinki led the investigation into the crater. The team included scientists from the University of Turku and international partners. Their combined expertise spanned geology, microbiology and isotope geochemistry to study ancient microbial habitats.

How Scientists Studied It? 

Researchers extracted core samples from deep beneath the crater lake. They analysed calcite and pyrite crystals for isotopes of carbon, oxygen, and sulfur. Uranium‑lead dating helped determine timing of microbial colonisation precisely.

Groundwater cooled slowly, reaching about 50 °C after several million years. Fractures and mineral-rich fluids created a stable environment for microbes. Findings suggest impact craters can act as long-term habitable zones.

Astrobiology Connection

This research provides clues about life beyond Earth’s surface. Impact-generated habitats on Mars or other planets may host microbial life. Crater fractures, heat, and fluids could sustain life over long periods.

Future Research Directions

Scientists aim to investigate other terrestrial craters for microbial signatures. Understanding these habitats may guide future astrobiology missions to Mars. These studies reveal how life adapts to extreme environments on Earth.