In the past 50 years, no team of divers has attempted to replicate the saturation-diving experiments dreamed up by Jacques-Yves Cousteau — creator of the Conshelf I habitat at 33 feet, and whose longest at-depth project spanned 30 days. His grandson, Fabien, is picking up that torch: originally slated for November 12 but now pushed back until Spring 2014, he will spearhead a 31-day mission 63 feet under the surface in NOAA’s Aquarius Reef Base habitat in the Florida Keys National Marine Sanctuary. His team will study the human/ocean connection, notably the physiological impacts of long-term diving. While some effects seem trivial — did you know taste buds go dull at 3 atmospheres? — some pack life-or-death consequences. For starters, little is known about the effects of accumulated nitrogen on stress and decision-making.

“The stakes can be extraordinarily complicated,” Fabien says. Recreational divers can retreat to the surface for air and safety, but saturation divers die if they do the same. Instead, they must return to the habitat on a path drilled into their minds and muscle memories, even if a mask floods or gear malfunctions. The team must also train to respond instinctively to fire or air-supply failure in the habitat.

“It’s like going to outer space — why would we want to do that?” asks Fabien. “The more we learn about our oceans, the more we learn about ourselves.”

Much of the research will be tackled with the aid of the latest in gadget including underwater motorcycles, autonomous robots and Kirby Morgan diving helmets. Cinematographer D.J. Roller will film the experience using 3-D IMAX cameras. What is perhaps most thrilling about the mission, says Fabien, is that every moment will be broadcast in real time. “The voyeuristic part of this is very real.”

» Learn more at mission-31.com.