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Astronaut Kathryn Sullivan Reaches Space and Deepest Parts of Sea to Inspire Next Generation of Scientists

Kathy Sullivan
Kathryn Sullivan. Credit: Enrique Alvarez.

What’s it like journeying to the deepest point of the Earth, nearly 7 miles under sea level, 35,000 feet deeper than even the most trained and seasoned scuba divers venture? For astronaut Kathryn Sullivan, the submarine plunge through deadly, crushing water, through frigid and inhospitable temperatures, to the deepest known point in the oceans—Challenger Deep, was like an extra-long elevator ride.

“It’s a very gentle, almost serene descent, that I would liken to a peaceful four-hour flight in a jet liner in economy with the seat belt sign on all the time,” the AAAS Member and former head of the National Oceanic and Atmospheric Administration (NOAA) says of the journey.

The expedition offered Sullivan a stark contrast from her previous career as a NASA astronaut, a profession that led to three trips to space in the 80s and 90s, which she has since described as like riding a bomb for a living. During her tenure at NASA, she also became the first American woman to perform a spacewalk. But before working as an astronaut, Sullivan’s interest in science was earthlier. In her 20s, she was working on her Ph.D. in geology at Dalhousie University, where she took several oceanographic expeditions that studied the deep seafloors of the Atlantic and Pacific Oceans.

The trip to the Pacific Ocean’s Challenger Deep came after an email invitation from explorer Victor Vescovo in the fall of 2019. For Sullivan, the opportunity to see the Challenger Deep, a mysterious and little-explored crevice in the sea and into the Earth’s crust, was just too good to pass up. The possibility of seeing strange and beguiling creatures, such as dumbo octopuses and “living fossils,” like the rare, deep-sea Goblin shark, was tempting for an adventurous person like Sullivan. But it wasn’t just about the journey.

Using her background in geology, Sullivan swiftly mapped scientific goals for her mission.

“My background was germane,” she says on why Vescovo invited her. “One of Victor’s key objectives was to nail down more precisely the depths and topography [of the Challenger Deep]. I drew on my own background and connections to arrange for NOAA to do an independent analysis of the Challenger Deep bathymetric data (depths and shapes of ocean terrain), to confirm the depth measurements and refine the error budget.”

The expedition’s approach had three prongs, which she describes as two independent multi-beam sonar surveys, the matching of measurements from the submersible with data from robotic landers, and collaboration with NOAA in order for their hydrographers to analyze the sub and lander data and do an assessment of their own.

The June 2020 dive took about four hours to go to the bottom of the Challenger Deep and another four to return to the surface. Used to tight spaces, Sullivan was quite comfortable on her vessel, the Deep Sea Vehicle (DSV) named Limiting Factor, a reusable submersible piloted by Vescovo.

Although the submersible is a small space, it’s not cramped, Sullivan says.

“You can shift around in your seat, you can move your legs a little bit if you get a little achy from sitting still for a long time. There’s a little bit of ability to relieve that... And you just descend at about a meter per second, which is just over two miles per hour. You can walk faster.”

While the trip for Sullivan was academic and serene, one aspect of the Challenger Deep shocked and disappointed her: microplastics. That is, learning that man-made debris, “a plastic bag and soda-pop can, and other isolated bits of visible garbage, plus microplastics” had made it into the deepest known point of the Earth.

Sullivan is aware that many people learning about plastic might think that the remote garbage is out of sight, and therefore out of mind, but she’s quick to call that attitude dead wrong.   

“There is no place on this planet that is not interconnected to every other bit of life on this planet,” she says. “It’s folly … to think that the oceans are huge, vast places that are beyond our reach and we’ve no need to care about them.”

Sullivan describes her current goal as helping to keep the oceans healthy, as both a scientist and advocate. But she’s also still interested in finding new ways to expand the frontiers of knowledge about the oceans. And, sometimes for her, that means defending the science.

As a former head of NOAA who served from 2013 to 2017, Sullivan found herself speaking out about the Trump Administration in 2019, calling the administration’s Hurricane Dorian statement 'mealy-mouthed' and 'disingenuous' in an interview with the Canadian Broadcasting Corporation. At the time, NOAA had come under intense scrutiny for issuing a statement admonishing its National Weather Service forecasters in Birmingham, Ala., for publishing a tweet that contradicted President Donald Trump's own public claims about Hurricane Dorian’s threat to Alabama.

For Sullivan, that debacle is only one example of how science is becoming highly politicized in today’s climate.

Sullivan snapped this pic of the Challenger Deep on her journey down. Credit: Kathryn Sullivan.
Sullivan snapped this pic on her dive down to the Challenger Deep. Credit: Kathryn Sullivan.

“I’ve been nominated more by Republicans than Democrats for my appointments. But where we are right now, I doubt that a Republican Administration would consider me for any post, simply because my last position was in the Obama Administration,” she says. “And it’s now become so hyper partisan that there are those who would say that [serving in the Obama administration] taints me forever, that my primary loyalty is their opposing party rather than to my country.”

Earlier in her career, Sullivan says administrations of both stripes welcomed well-credentialed scientists into their ranks and placed a much higher degree of confidence in their advice and information. That too has now fallen apart to an extent, which worries her. Yet, while Sullivan is frustrated about the lack of trust, she has solid advice for other scientists who feel the integrity of their disciplines are under attack.

“I think it’s important for every member of the scientific community to raise their voice loudly and as frequently as they can about the importance of scientific integrity,” she says. “Yes, science is a human enterprise, and yes, humans are fallible, but the best scientific and technical knowledge we have are tremendously valuable inputs to national decision making.”

Beyond scientists defending science and expanding research to the outer frontiers in space and the oceans, Sullivan also hopes to see more support for young women and girls beginning their studies and careers in STEM fields. That was one of the main reasons she says she took the journey to the Challenger Deep, to inspire young people, particularly young girls.

Working in partnership with COSI, Ohio’s Center of Science and Industry in Columbus, the science museum that Sullivan ran for about a decade, as well as an education center called the PAST Foundation and the Monterey Bay Aquarium, she hopes to develop an immersive and engaging educational content platform. The process is just beginning, but she says the program will be very digital, especially because of COVID-19. For her part, Sullivan still believes change is needed at a much broader level to encourage young girls and women in STEM. She hopes to see more institutional solutions which address gender and sexual-based harassment and discrimination.

“In these #MeToo times, I think there’s been some slow improvement and continued slow progress, but so much more needs to be done,” she says. “It’s crazy trying to tackle the future with just 50 percent of the nation’s talent base or less than that. Leaders have to step up and take a clear ‘not in my shop, that’s not who we are and not how we work’ stance on toxic behavior. It’s has to start with leadership, but it’s going to take all of us.”

Representative Image Caption
Kathy Sullivan. Credit: Enrique Alvarez.
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Emileigh Clare