If you were to take a very large breath and plunge seven miles down to the Challenger Deep, the deepest part of the world’s oceans, you would not, as it is commonly assumed, be crushed like a soda can. Ambient pressure increases with every “atmosphere” (10 m, or 33 ft) you descend. Seven miles below the surface there are nearly 17,000 pounds of pressure per square inch, over 1,000 times greater than the ambient pressure at sea level. That is enough to crush a titanium-hulled nuclear submarine like a soda can, but incidentally, nowhere near enough to crush a human bone. Our bodies are, after all, seventy percent water, a substance that is almost impossible to compress.
The trouble would come from those little places in your body that contain air. Your ear-drums and sinuses, if un-equalized, would rupture, any teeth with fillings would implode, and your lungs would compress to the size of raisins. All of these things are unpleasant, but not fatal, and while we assume that there would be other nasty affects, like the chemical denaturation of certain proteins and pulmonary edema, we’re not sure exactly what.
That Doesn’t Stop Everyone
Precisely how deep a person can dive remains a mystery, right along with many of the other questions surrounding life on Earth’s last frontier, the deep oceans. Until the 1960s, it was assumed that diving below 100 m (328 ft) was physiologically impossible. The current free-diving depth record stands at nearly three times that: 273 m (895 ft) and counting. Sperm whales, the deepest diving mammals, have been recorded as low as 6,000 ft. Life, in the form of bacteria, is known to exist at pressures of over 4,000 atmospheres, the equivalent of 26 miles below the ocean floor.
Given those terrible forces, you can understand why people have been reluctant to explore the deep. In fact, 95% of the world’s oceans remain unexplored. Some of the most compelling of those percentage points lie in the bottom of the Mariana Trench where sections like the Challenger Deep sit deeper than Mt. Everest is high. Until this week, the only two people to ever see it went in 1960 as part of an American naval expedition. They stayed for 20 minutes, then left without taking any photographs. Since then, more men have walked on the moon than visited the deepest part of the sea.
On March 25, film director James Cameron, famous for his big-budget extravaganzas like Titanic and Avatar, became the third man to reach the bottom of the Challenger Deep. He did so not as part of a larger, government-sponsored program of exploration, but as a privately funded (by National Geographic, Rolex and Cameron’s own bank account) mission of gathering content for at least two planned documentaries: A wide-screen theatre version, and a National Geographic television special. By touching down on Sunday, he has beaten fellow mega-millionaire Richard Branson as well as a few other teams racing to develop deep-diving subs. They include the Florida-based Triton submarines, who hope to one day charge tourists $250,000 a pop to ride through the Trench in their specially designed submersible.
Predictably, internet commentators have already begun to bemoan the privatization of scientific exploration and the “commodification” of scientific knowledge. On one hand, the criticism is pertinent: if Cameron were really as dedicated to science as he likes to let on, he would have checked his boyish enthusiasm and sent an expert, like Robert Ballard or other researchers he has collaborated with on the project, down into the Trench. Despite the elevated rhetoric generated by Cameron and his expedition, the project carries the unmistakable whiff of Phileus Fogg, the bored, aristocratic protagonist of Jules Verne’sAround the World in Eighty Days whose journey was based on a bet made after too many brandies at the gentleman’s club. When he finishes, he’s convinced he has lost because, absent-minded old chap that he is, he forgot to reset his watch at the International Date Line.
On the other hand, singling out Cameron for being a little cavalier and perhaps having motivations that aren’t limited to scientific altruism ignores much of the history of the entire business of scientific exploration—a history in which mercantile gain and scientific good have often been indistinguishable. Consider the archetypal, pith-helmeted, bushy mustached explorer employed by governments or international trading cartels to scour the globe for trade routes and areas ripe for colonial acquisition. Science was sometimes a priority, but often an adjunct.
The scientific information gleaned from expeditions was often subject to the whims of the market. As an example, it was common practice around the time that James Cook bumped into Australia in the late 1700s to confiscate all journals kept by sailors on journeys of discovery so they couldn’t sell them to journalists before larger enterprises, like the Royal Society, could publish the “official account,” usually written by the captain or an officer.
As travel became more accessible to the wealthy throughout the 1800s and 1900s, so, too, did the title of “explorer.” Men like Mungo Park and John Hanning Speke, who explored the interior of Africa on separate expeditions, were both talented and educated, but neither could be considered one of the preeminent scientists or navigators of his day, like Alexander Von Humboldt or Captain Cook. Instead, Park and Speke are both good examples of men who became explorers with the help of the right connections in English society and a shared predilection for suffering that bordered on the sadomasochistic.
Cameron is an explorer in that same vein. His achievement, which he tweeted from the bottom of the ocean (naturally), isn’t a paradigm shift, it’s a continuation of this process.
Today, the privatization of space flight has heralded a general trend towards privatization of exploration in many arenas, the effects of which aren’t yet clear. Of the things you can fault Cameron for (ahem, Avatar), his enthusiasm and vision are not among them. It’s been 52 years since any government has even been interested in putting a person in the Challenger Deep. If not for Cameron, Branson and the rest of the billionaire boys club, that would not have changed, and we’d be worse off because of it.
Still Deep Questions
There is still so much that science doesn’t know about what happens beneath the waves. Some are small questions, and some concern the future of the human race. Whatever Cameron’s reasons may be for venturing into the depths, he and his ilk now have the opportunity to do an important thing: make people care about the 70% of the globe that is covered in water.
He’s hasn’t achieved this yet. What he has accomplished is damn cool, but otherwise somewhat insignificant. If he wants to turn his feat from the deepest ego trip in the world into something more substantive, he’ll have to do what many explorers have historically been incapable of: take a step back from the limelight. By getting out of the cockpit of his sub and sending marine biologists, geologists and oceanographers down in his stead, he can give rise to a new era of undersea exploration that, in conjunction with his arrestingly visual works of cinema, can expand the known limits of humanity.
If he can’t do that, he’s just Phileus Fogg, a man who can do laps around the globe but can’t be bothered to re-set his watch.