Armed with better batteries and stronger materials, new submersibles aim to go deeper than ever before and open up the whole of the unexplored ocean to human eyes.
By liberal estimates, we’ve explored about 5 percent of the seas, and nearly all of that in the first 1,000 feet. That’s the familiar blue part, penetrated by sunlight, home to the colorful reefs and just about every fish you’ve ever seen. Beyond that is the deep — a pitch-black region that stretches down to roughly 35,800 feet, the bottom of the Marianas Trench. Nearly all the major oceanographic finds made in that region—hydrothermal vents and the rare life-forms that thrive in the extreme temperatures there, sponges that can treat tumors, thousands of new species, the Titanic — have occurred above 15,000 feet, the lower limit of the world’s handful of manned submersibles for most of the past 50 years.
Now engineers want to unlock the rest of the sea with a new fleet of manned submersibles. And they don’t have to go to the very bottom to do it. In fact, only about 2 percent of the seafloor lies below 20,000 feet, in deep, muddy trenches. If we extend our current reach just 5,000 feet — another mile — it will open about 98 percent of the world’s oceans to scientific eyes.
Flying Low: The Deep Flight II sub uses stubby wings that propel it down like an airplane goes up. Nick Kaloterakis
The payoffs could be huge. Mining companies hope to search hydrothermal vents for minerals like nickel; gas and oil companies are eager to explore the seafloor for new energy sources; and marine biologists want to study how climate change has affected deep ecosystems. In addition, there’s simple curiosity of the man-versus-nature sort. With all the world’s highest peaks summited and both poles trampled, the deep seas are a ripe frontier.
But sending a vehicle that deep requires serious cash and engineering. The craft must be small enough to move on battery power and sturdy enough to withstand immense pressure — 10,340 pounds of water per square inch at 23,000 feet, equivalent to having a school bus on your head. A manned submersible has to meet even higher standards: It must keep its occupants alive.
► Read the complete article here.