The European Space Agency, along with the Portuguese Space Agency and the Portuguese Navy, are turning to submarines to learn about living in space.

By simulating the tight, isolated conditions astronauts endure during space missions, these underwater voyages shed light on how humans might cope far above the sea level—into the cosmos.

The first team involved in the SubSea project just wrapped up a two-month underwater adventure, mimicking the challenges found during long-term space missions.

A crew of 25 volunteers, backed by experts from Germany, Italy, and Portugal, experienced life in the cramped quarters of a submarine, offering a glimpse into the stresses and strains of space travel.

According to ESA astronaut Andreas Mogensen, who’s spent six months on the International Space Station, the insights from these aquatic expeditions are crucial.

‘SubSea is key in understanding how we handle extreme situations,’ Mogensen noted. ‘The findings help us grasp how we can live and work in places that test our mental and physical limits—be it under the ocean, out in space, or remote areas on Earth.’

ESA’s Daniel Neuenschwander, the Director of Human and Robotic Exploration, echoed these sentiments.

He pointed out that the challenges faced on the Space Station, like microgravity and space radiation, are closely mirrored by the SubSea project.

‘Understanding these harsh conditions is critical as we gear up for upcoming journeys to the Moon, Mars, and even farther,’ Neuenschwander explained.

Beyond space travel, the results from the SubSea mission could have wider benefits. They might help improve healthcare in remote and isolated regions—from polar bases to military encampments, and even aid in addressing mental health issues such as depression and sleep disorders.

Ricardo Conde, president of the Portuguese Space Agency, emphasized Portugal’s vital role in this research.

With unique locations like the Capelinhos Volcano and the Selvagens Islands, Portugal is not just a participant but a leader in space and analogue research.

As the SubSea mission moves forward, it continues to set the stage for breakthroughs that stretch from the ocean depths to the outer edges of our universe, proving that sometimes, to reach for the stars, we must dive into the sea.