When Carolynn Box left for her first 5 Gyres research expedition in 2011, it was Christmas Eve. She talked her way onto the organization’s trip, and had been peppering the ship’s captain with safety questions for weeks. She traveled with a friend from San Francisco to Namibia to meet up with the 5 Gyres boat, which was set to comb the vast South Atlantic Ocean gyre for plastic waste. She was abuzz with nervousness.

“I’m not a professional sailor … I was scared of sinking, or things going wrong during a really big storm. I didn’t want to die,” says Box.