Volcanic caves of Mount Erebus unveil new secrets about survival in extreme conditions

In a recent article, Indian Defence Review highlights that beneath the icy expanse of Antarctica lies a hidden world where fire meets ice, and life thrives in the most extreme conditions imaginable.

In the subterranean ice caves of Mount Erebus, scientists have discovered a vibrant microbial ecosystem, revealing new possibilities for life on Earth—and potentially beyond.

Standing 12,448 feet (3,794 meters) above Ross Island, Mount Erebus is a striking anomaly in Antarctica's frozen wilderness. Unlike most volcanoes, Erebus boasts a permanent lava lake and an intricate network of underground ice caves. Geothermal heat melts pathways through the ice, creating a constantly shifting maze of tunnels that refreeze over time.

Inside these alien-like caverns, temperatures can soar to 77°F (25°C), providing a stark contrast to the frigid -100°F (-73°C) Antarctic winters above. Massive fumarolic ice chimneys, some as high as 30 feet (9 meters), vent volcanic gases that crystallize into bizarre formations. The cave walls sparkle with hoarfrost, and sunlight filtering through the thin ice casts a strange, eerie glow over the frozen landscape.

Scientists investigating these ice caves have uncovered a thriving microbial ecosystem unlike any other found on the continent. The bacteria and fungi are not just surviving but flourishing in complete darkness, far from any sunlight.

Many of these microbes have no close relatives elsewhere on Earth, with some of their DNA sequences completely unrecognized, suggesting the potential discovery of entirely new species.

What’s even more intriguing is how these microbes survive in such a hostile environment. While most life on Earth relies on photosynthesis, these microbes use chemosynthesis, deriving energy from chemical reactions with volcanic gases. A 2015 study in Frontiers in Microbiology revealed that these organisms fix carbon using the Calvin-Benson-Bassham (CBB) cycle—a process typically associated with photosynthesis. Instead of sunlight, these microbes use carbon monoxide (CO) and hydrogen (H₂) from Erebus’s volcanic vents.

In one of the caves, Warren Cave, scientists discovered bacteria that feed directly on volcanic emissions. The isolated nature of this environment revealed no traces of Archaea, a microbial group typically found in other extreme conditions like deep-sea vents. This suggests that Erebus’s ecosystem has evolved independently of other extreme habitats on Earth.

This hidden world of life flourishing underground, fueled by volcanic gases, might seem like science fiction. However, for NASA, Erebus’s ice caves could be the closest real-world analogy to an alien environment on Earth.

If life exists beyond our planet, it could be thriving in similar environments beneath the icy crusts of moons such as Jupiter’s Europa or Saturn’s Enceladus, where geothermal heat might create comparable subterranean habitats.

To prepare for future space missions, NASA’s Jet Propulsion Laboratory (JPL) has been using Erebus’s caves as a testing ground for robotic exploration technologies. Among the tools deployed is PUFFER, a foldable robot inspired by origami, designed to navigate narrow, icy crevices. Equipped with ice-drilling capabilities and chemical sensors, this robot can detect organic molecules—technology that may one day be used to search for life beneath the icy surfaces of distant moons.

The discovery of thriving microbial life in Erebus’ volcanic caves strengthens the argument that similar life forms could exist beyond Earth, waiting to be uncovered in environments we are only just beginning to explore.

By Naila Huseynova