Journalist Ben Hellwarth is the author of the new book SEALAB: America's Forgotten Quest to Live and Work on the Ocean Floor.
Back in the 1960s, it looked as though the space race might be matched by a race in the opposite direction.
As the first astronauts were going up, blazing a celestial trail to the moon, a visionary group of scientists and divers in the US Navy was working its way down into the unexplored sea, a realm some liked to call "inner space." Others got into the race, too, including Jacques Cousteau and the American inventor Ed Link. They all believed that equipping "aquanauts" to live and work in the sea was at least as important as launching astronauts into space. Even more so.
"Sealab" was the name given to the Navy's prototype sea dwellings, and to the larger program that became the world's leading demonstration that human divers could swim much deeper and stay underwater far longer than ever thought possible -- for hours and days instead of mere minutes. They just needed the right gear, the right recipe of gases to breathe, and a functioning, pressurized shelter like Sealab nearby.
That may sound relatively simple, but conditions underwater are every bit as daunting and dangerous as in space, as I was repeatedly reminded while doing the research and personal interviews for my book, SEALAB: America's Forgotten Quest to Live and Work on the Ocean Floor. You can't help but admire the cast of fearless characters who put their lives on the line to prove that Sealab was not science fiction (and should not these days be confused with Sealab 2021, the ultra-cheeky sci-fi Cartoon Network series).
As the 43rd anniversary of the Navy program's sudden demise approaches, this slideshow pays tribute to the pioneers who broke age-old depth barriers and opened a new frontier to human exploration and even occupation.