Edmund Hillary and Neil Armstrong are two explorers who have become household names -- but what about Bill Stone and Alexander Klimchouk? In 2004, both men attempted to find the deepest cave on Earth -- Stone explored southern Mexico's Cheve cave, and Klimchouk delved inside the freezing Krubera, a supercave in the Republic of Georgia. Author James Tabor has documented their intrepid search in his new book, Blind Descent, which he discusses with NPR's Guy Raz.
Inside A Supercave
So what exactly is a "supercave"? Think of Mount Everest, and now picture it in reverse ... and that's your basic supercave.
Tabor says the great Georgian cave Krubera is 7,000 vertical feet deep -- somewhere along the size of seven Empire State buildings. Mexico's Cheve, which is shaped like a giant L, goes as deep as about 2,500 vertical feet on the vertical side and 5,000 feet deep on the horizontal side.
The cavers who explore supercaves have to be ready for just about anything -- including flooded tunnels called "sumps." When they encounter a sump, cavers can either stop or put on scuba gear and charge ahead.
Spaces inside the caves vary widely, Tabor says. "They can be very very tight -- near the diameter of your garbage can -- or they can be immense, like a New York subway tunnel."
Occupational Hazards
Drowning, poisonous gas inhalation and electrocution are perils of journeying through a supercave. Tabor says there are more than 50 ways for a person to die during these explorations.
There's also a danger of developing an illness known as "the rapture" -- an extreme reaction to darkness and depth. Those who have suffered from it describe it as being similar to an anxiety attack while on methamphetamines.
"At some level, everyone's brain will start to say, 'I don't belong here. This is a very dangerous place.' It's an ancient primordial instinct and it just says, 'You have to get me out of here, right now,'" Tabor explains. "Luckily Bill Stone and Alexander Klimchouk -- most of their veteran team members did not have any rapture attacks."
Worth The Schlep?
Despite the dangers, supercave exploration can pay off; it's not just a chance to brag about being the first to reach the deepest point on earth. Scientists have found life forms called extremophiles, which are providing new families of antibiotics that seem to be effective against drug-resistant bacteria. And NASA is interested, too.
"NASA itself is fascinated by the stressors that attack these teams that are underground for a month or so," Tabor says. "They replicate better than any simulation could, the conditions that their Mars crews will encounter."
Tabor says that when you consider the dangerous risks and the technical demands that are required to make these discoveries, supercave explorers deserve the same recognition as mountain climbers or astronauts.
"I would absolutely put them in that category," Tabor says. "People need to know what these fellows did."
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