// SPACE.COM — SPAZIO & SCIENZA
An aquanaut comes home: Returning to Earth from an undersea 'space station'
Living under pressure can significantly impact the cognitive abilities of aquanauts — people living underwater for more than a day.
When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.
Our time on our "space mission" underwater was coming to an end, and I felt like what I imagine an astronaut on the International Space Station (ISS) must feel before returning to Earth. On one hand, you are excited to return to your home and loved ones, as well as to fresh food and normal hygiene. On the other, you know you will miss your crew and the incredible experience of being in space.
While my SEA STAR crew and I had not left Earth during our mission, we were separated from the surface of our home planet for five days. All we saw was a green alien water world surrounding us. We did this to live and work like astronauts on the ISS. Instead of dealing with the challenges of space that astronauts face, we problem-solved sometimes equally difficult issues that divers have to manage when performing research in sea water.
Our "wet ISS" was the Jules' Undersea Lab, which is located near Key Largo, Florida, at 22 feet (7 meters) underwater. By the end of our mission, we had all officially become aquanauts. An aquanaut is an undersea explorer who remains underwater for more than 24 hours, without returning to the surface, in a state known as saturation.
In this sense, saturation refers to the physiological condition achieved by a person who breathes underwater long enough for the body's tissues to absorb the maximum possible amount of inert gas (like nitrogen), for a specific depth and pressure. The term aquanaut derives from the Latin word "aqua" (water) and the Greek "nautes" (sailor).
There were a lot of things I wasn't going to miss about being an aquanaut. They included the constant loud noises our life support systems made to keep us alive underwater, as well as bathroom plumbing issues and some health concerns linked to living under pressure. We also had to be very careful when performing our "spacewalks" (scuba dives), due to the low visibility of the environment around us.
Nonetheless, I experienced a sort of "underview effect" during this mission. Most astronauts report experiencing an "overview effect" after seeing our whole planet from space, which usually makes them value our unique planet even more. I felt a similar thing when I saw the sun's rays come through the water. I couldn't reach them, but I enjoyed them from afar. My everyday life felt so close, yet so far away. It gave me both a feeling of longing and more determination to take even more care of our home world than before.
I'm grateful that we were able to perform all of the different scientific projects we planned for our mission. As the Commander of the crew, I usually have my work cut out for me managing the crew and overseeing their research projects, as had been the case for most of the 40 simulated space missions that I led previously. Fortunately, this time my crew was made up of experienced analog astronauts and divers, so the mission was mostly smooth sailing.
The research we chose for this mission was relevant for long-duration space missions. Since we can only send a small number of astronauts to the ISS with a limited number of research activities to perform, underwater stations provide us with a valuable way to conduct analog, or simulated, space missions instead. We also performed some environmental conservation work using a type of underwater vacuum device to help protect the nature around the Jules' Undersea Lab.