LULU GARCIA-NAVARRO, HOST:
Kathy Sullivan, an American geologist, has made history again. This past week, she became the first woman to reach Challenger Deep - that's the deepest point on the surface of the Earth. It's in the Mariana Trench, nearly seven miles down from the surface of the Pacific Ocean. And we've caught up with her aboard a ship near Guam. She's on a satellite phone. Kathy Sullivan, congratulations. And thank you so much for being with us.
KATHY SULLIVAN: Thank you, Lulu. Glad to talk with you.
GARCIA-NAVARRO: So many of us will never be able to go that deep. What was it like in Challenger Deep?
SULLIVAN: My top-of-mind impression was that it was a moonscape. That's the image that kept coming to mind as we flew across the bottom of 2 meters, about six feet off the bottom along our traverse, relatively flat-looking sediment on the bottom. Signs of critters - I mean, it's known from earlier scientific investigations, but there is some life down there. Critters called amphipods, which are kind of large versions of the pill bugs that you might have in your yard. Certain kinds of worms, a variety of sea cucumbers and some anemones.
GARCIA-NAVARRO: What kind of vehicle were you in, and how long did it take you to go down that far?
SULLIVAN: So I was in a submersible. You're 4 1/2, 5 feet in diameter. Its walls are solid titanium, about 3 1/2 inches thick. And it's that titanium shell that keeps away from our little bodies the immense pressures of the deep. How long does it take to go there? It's essentially 36,000 feet deep, so it's seven miles. That's half the length of Manhattan Island. So if you go to your maps application on your phone and put in a route that says take me from the south tip of Manhattan halfway up the island, how long will that take me? This app will tell you two hours. And it took us four hours to get to the bottom. So we descended, like, at about half the speed that you could walk.
GARCIA-NAVARRO: And what were you there to do?
SULLIVAN: It ranges from studying the sediments, looking at the genetics of the materials, the living material that you find both in the sediment and in the water, taking water chemistry samples to see what sorts of trace elements from human life make it down that deep, if any do. We're trying to do what are called mapping transects - so go from point A to B to C to D with a set of instrumentation that lets us refine the depth measurements, getting some of these amphipods and other critters and studying them intensively, again, to understand their genetics, to see what species they are. So a very far-ranging program.
GARCIA-NAVARRO: Now, I said you made history again in your introduction because we should say you've also been to space three times. And in 1984, you became the first American woman to walk in space. Are there any similarities to the bottom of the ocean? You're one of the few people who could make that comparison.
SULLIVAN: Yeah, I find several similarities and, of course, some differences. When you launch off the planet, you feel like you're embedded in a gigantic ball of energy. It's an explosive, turbulent, massive amount of power. And when you go down into the deep of the ocean, it's a comparatively really serene experience. It was like a magic carpet ride, just sort of slowly descending straight down. But the similarities are also there to me, as well. In each case, I'm in a vehicle - I'm in a craft that has been innovated and engineered to keep inside of it the kind of conditions humans need to survive, you know, sea level kind of pressure, oxygen, nitrogen to breathe, a reasonable temperature range, life support, human waste. We humans are clever enough. We can create these vehicles that let us go to places that we otherwise have no business at all being.
So when I would look out the window of the space shuttle in my shirt-sleeve, maybe sipping my coffee, maybe listening to a playlist - right outside that window, there's no air. There's a hard vacuum of space. The harshness of space - you die instantly if your body is exposed to that. And it's the same but in reverse inside the submersible. As I look down at the floor of the Challenger Deep, I'm sitting in a comfortable, sort of shirt-sleeve environment. Got my water bottle nearby. I'm looking at this amazing landscape. And right outside that window, if I were outside instead of inside, you know, you would not survive. That always struck me as a really, you know, mind-bending experience to feel so happy, comfortable, secure and able to just be curious and useful where I am inside, knowing that, outside, it's impossible for me to exist.
GARCIA-NAVARRO: Is that what draws you? I mean, why have you pushed yourself to go to outer space and then also the deepest place on this planet?
SULLIVAN: Well, I was an oceanographer before I was an astronaut. And the driving force in my career all the way through has been a really intense curiosity about Earth, our planet, its geography, its geology, its everything. How does it work? How well do we understand it? And how well can we bring that knowledge and understanding into our own daily life to make wise decisions, better decisions about how we live on this planet? I'm an explorer. I want the data. I want the knowledge. I want the understanding. So, you know, too curious for my own good, I guess you'd say, is the bottom line. But it's worked out real well.
GARCIA-NAVARRO: I'd say so. That's Kathy Sullivan speaking via a satphone provided by EYOS Expeditions. She's traveled to space and now the deepest point in the ocean.
Thank you very much.
SULLIVAN: Thank you, Lulu.
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