At the southern end of the Mariana Trench, a deep scar that cuts into the bottom of the ocean floor, there is a point known as Challenger Deep. Here, just outside of the Marianas or Ladrones, a series of 15 islands made up of volcanic mountains that peak just above the water line, a small slot-shaped valley plunges nearly seven miles down. At 35,797 feet, Challenger Deep is the deepest known point in the oceans. It is so deep that, if you were able to place Mount Everest inside of the valley, there would still be 6,811 feet of water separating it from the surface.
At just 7,000 feet down, about where the tallest mountain in the world would peak, the pressure becomes so great that whales rely on unique evolutionary traits when hunting for giant squid. Whales have lungs that can collapse safely under pressure and ribs bound by soft cartilage that allows the cage to shift and settle in extreme environments rather than snap. Without similar anatomical gifts, we don't know much about what happens below that level. Imagine what creatures might live at depths five times greater than where whales and giant squid battle in the pitch-black ocean.
We've been there once before, to the bottom of Challenger Deep. But we didn't see or learn much. On January 23, 1960, Jacques Piccard suited up, plopped down inside of Trieste, and sank to the ocean floor. The Swiss-designed, Italian-built, U.S. Navy-owned Trieste is an inelegant machine. The observation gondola, a sphere welded to the bottom of the ship's main flotation system, has walls that measure five inches thick and a tiny, cone-shaped Plexiglas window.
After spending nearly five hours sinking to the bottom of the ocean, Piccard and Don Walsh, a Navy Lieutenant that accompanied him, were only able to peer through the Plexiglas while shivering in the 45-degree capsule and munching on chocolate bars for sustenance. Surrounded by a cloud of sediment that Trieste had kicked up when it smacked into the ocean floor, Piccard and Walsh couldn't see a whole lot from their window, which had cracked on the way down. What they did see, though -- a variety of sole and flounder, two types of flatfish -- proves that at least some vertebrate life can handle the extreme pressure in one of the Earth's most extreme places. Twenty minutes later, Trieste dumped tons of magnetic iron pellets and spent three hours rising back to the surface.
Now, more than 50 years later, humans are nearly ready to return to Challenger Deep. This time, though, they're planning to stay a while, collecting samples, videotaping whatever might be down there, sending out small remotely operated underwater vehicles (ROVs) and then bringing home $10 million. Earlier this year, the X Prize Foundation made that prize money available to the first privately funded submersible to make two visits to Challenger Deep. This money, though, is little more than proof that humans are fascinated with the extreme: climbing Mount Everest, walking on the Moon, searching the floor of the ocean. Ten million dollars will only cover a fraction of the race to the bottom. And it is indeed a race; one with at least three competitors, each close to claiming the prize.
Billionaire Richard Branson is known for the hundreds of companies that fall under the Virgin Group umbrella, including Virgin Megastores, Virgin Atlantic Airways, Virgin Records and Virgin Galactic, his space tourism company that aims to bring passengers into sub-orbital space for $200,000 a head. As part of his team perfects SpaceShipTwo, the plane that will fly more than 60 miles above the Earth as those inside gleefully float about the cabin for six minutes of weightlessness, another crew is busy preparing a kind of ship meant to take humans in the opposite direction.
