The United States has been out of the space shuttle business for a few months now, but the country is still seriously considering spending billions of dollars to send astronauts back to the moon, to Mars or to a nearby asteroid.
It’s heartening that the pioneering spirit behind crewed missions into outer space has not been dampened by the nation’s tide of red ink. But with price tags like $50 billion to return astronauts to the moon in the next decade, there’s a strong bang-for-the-buck argument to be made for far less expensive missions headed in the other direction: down into the ocean depths, which remain largely unexplored and unseen by human eyes.
The nation’s limited experience with undersea missions has nonetheless shown the great potential for scientific and technological advances and valuable spinoffs that come when public investments are made in bold exploratory ventures.
In 1969, an accidental death helped sink the United States Navy’s Sealab program. A diver’s breathing gear apparently malfunctioned in the dark cold just outside the lab, an astounding 610 feet below the surface. It was a sobering reminder of the inherent risks of making prolonged deep dives. The risks include not only the bends — the painful and potentially lethal consequence of surfacing too rapidly — but also breathing exotic gas mixtures (ordinary air becomes toxic beyond certain depths and pressures) and exposure to the frigid temperatures of the deep sea. Conditions underwater can be every bit as hostile as in space.
Sealab had been showing the way toward establishing outposts on the ocean floor, albeit in the shadow of NASA’s space program. The Navy program achieved major breakthroughs that made it possible, for the first time, to house free-swimming divers on the seabed, and at far greater depths than ever thought possible.
Unlike conventional divers, who are limited to brief forays from the surface, these aquanauts — as sea-dwelling divers have been called — could not only reach greater depths, but they could also stay down for an indefinite period, spending hours at a time in the water instead of minutes, provided they had a pressurized, climate-controlled shelter nearby. The advent of the aquanaut meant that a vast and varied submerged frontier was open to human exploration.
While the Navy had an interest in science and exploration, it was mainly concerned with what aquanauts could do for the military, like recovering sunken aircraft, ships or downed submarines.
One of the beneficiaries of the Sealab program was the offshore oil industry. The revolutionary diving methods devised for Sealab emerged just as the industry was moving into deeper waters and needed an expanded underwater work force that could handle both increased depths and longer durations. The industry customized and streamlined its approach so that commercial divers could put in full-day shifts on the seabed without actually having to live down there.
The Navy ultimately gave up on Sealab and sea bases, largely because they didn’t suit its military priorities. The program was shelved after the accident in February 1969, a few months shy of the first moon landing. But the Navy continued to use its newfangled diving methods in other operations — like top-secret missions to spy on the former Soviet Union. This involved housing deep-diving aquanauts on submarines rather than in a stationary base like Sealab.
Several dozen science-oriented underwater shelters came and went around the globe, including a few made in the United States. Most were productive but relatively low-budget affairs, as is the United States’ only remaining sea base, which is also the world’s only such base. It’s an otherworldly looking structure called Aquarius, about the size of a city bus, which is owned by the National Oceanic and Atmospheric Administration and run by the University of North Carolina, Wilmington. It gets by on less than $3 million a year, compared to, say, the cost of a single shuttle mission, which NASA has estimated to be $450 million (other estimates have been considerably higher). The entire Sealab program cost taxpayers about $20 million; close to $20 billion was spent during the same period to reach the moon.
Since the early 1990s, Aquarius has been stationed on a coral reef a few miles south of Key Largo, Fla., in water about 60 feet deep. There, it has carried on the legacy of Sealab by serving as a valuable undersea vantage point for scientists. Dozens of scientist-aquanauts have published 300 research papers over the course of about 120 missions, ranging in duration from a few days to a couple of weeks. Examples of the work made possible by these underwater stays include ocean acidification studies and examinations of how herbivore diversity may be manipulated to conserve and restore degrading reefs — knowledge critical to life on earth.
Archaeologists would benefit greatly by having an underwater base of operations. So might commercial interests in search of mineral deposits. And as in space, one line of inquiry may open the door to another.
Remotely operated probes, robots, sensors and vehicles, known as R.O.V.’s, also have their place in ocean research, much as they do in space. Such machines can be more cost effective, reach greater depths and keep human beings out of harm’s way. The government’s own Okeanos Explorer, a converted naval surveillance ship, is making impressive use of R.O.V.’s and other devices to churn up reams of data about the seafloor while engaging many scientists in its process of discovery. But sometimes there’s just no substitute for the presence of a sentient human, perhaps no more so than in the dynamic, living realm of “the silent world,” as Jacques Cousteau famously called the sea. Marine scientists who have experienced the aquatic life will tell you: there’s nothing like living in the sea to gain a better understanding of it, for much the same reason that Jane Goodall lived in the jungle.
Besides accomplishing their intended goals, scientists are able to see and experience the unexpected, at any time of day or night, and new revelations await — like the discovery of a marine plant or animal that could produce the next wonder drug. In the meantime, getting better acquainted with our home planet, at prices we can afford, is reason enough to continue paying for Aquarius, expand its capability and replicate it elsewhere in the silent world.
By Ben Hellwarth, the author of Sealab: America’s Forgotten Quest to Live and Work on the Ocean Floor.