Mars needs this woman
UC Davis scientist Dawn Sumner's work here on Earth might answer whether there's life out there
There’s a rock on Dawn Sumner’s desk: glossy, shimmering with swarms of floating black specks and strands. Just a few inches in diameter, it makes a pretty paperweight, albeit one that holds down just a fraction of the reports and notes cluttering the scientist’s desk.
“This rock is 2.5 billion years old, and all the black is little teeny bits of organic carbon that are encased in the rock,” Sumner says, holding the piece up to the light. “This was once a slimy mess at the bottom of the ocean, and it got captured and fossilized in the minerals.”
Sumner, a geology professor at UC Davis, plucked the rock from a ridge formation in South Africa in 1992. But its epic history may hold clues to lake beds near the South Pole and even some approximately 600 light-years away.
The living microorganisms contained in this fossil and others like it, she says, are useful in helping to find evidence of life on Mars.
Sumner’s interest in the subject is legit. The professor and chair of UC Davis’ Earth and Planetary Sciences Department also counts “astrobiologist” as a professional title. As a member of NASA’s Mars Science Laboratory, she works with a team of scientists and engineers to guide the rover Curiosity’s journey as it explores the terrain and geological history of the distant red planet.
This galaxy-based work has strong ties to Sumner’s work at UC Davis and the Antarctic. It’s also a marquee job that’s turned Sumner into something of a literal rock star.
Still, despite the prestige, Sumner faces challenges. Mainly, she bemoans a lack of time. And, not unlike many of her female peers, says she hasn’t been immune to industry sexism. The latter is just one reason she’s made mentoring young women a cornerstone of her work.
On this particular day, however, Sumner’s thoughts have drifted back into space. There’s been news lately about Mars One, the Netherlands-based nonprofit project that aims to establish a human settlement on the planet. A Folsom woman has been tapped as a possible candidate for a one-way flight into space’s final frontier, and whenever a local media outlet reports on the story, it turns to the geologist for expert insight.
Sumner gets the hype. “There’s a big part of me that’s an explorer,” she says. “And that is funneled into my science.”
The Mars trip, of course, is one-way. No coming back, no coming home.
It’s a true do-or-die adventure, she says with a smile. One that epitomizes a millenniums-old spirit of discovery.
“For centuries people have been setting sail for parts unknown, not knowing if they would die.”Search for life on Mars (and other galactic pursuits)
It’s mid-afternoon on a weekday in April as Sumner works in her third-story office inside the campus’ Earth and Planetary Sciences building. Today, she’s joined by two students: Marisol Juarez Rivera, a graduate student in geology, and Frances Rivera-Hernandez, a Ph.D. candidate in geology.
In person, Sumner appears unassuming. She usually dresses in warm, natural tones—shades of earthy brown and mossy green—and boasts a warm smile. She tends to speak quietly, thoughtfully—a trait that seems to make those around her try even harder to take in her words. Such is the case today with her students, who’ve pulled up chairs to huddle closer to their professor.
Sumner is set to dial into NASA for a LAPM—a Look Ahead Plan Meeting—the daily phone conference between the Curiosity mission’s various scientists and engineers.
It’s a job nearly 15 years in the making.
“I didn’t expect to work on other planets. But in 1999 or 2000, NASA decided they wanted to integrate the search for life into the Mars Exploration Program,” she says.
At the time, Sumner, who was part of an astrobiology committee, was asked to co-lead a group and help redefine its goals. Her background studying early Earth and the link between microbial rocks and evolution pushed Sumner to take her research further.
“I started working on how you would actually do the science on Mars when you’re looking for something that may or may not exist,” she says.
Specifically, life, or evidence of it.
After Sumner shared her group’s work with the Mars Science Laboratory, she was selected to work on a proposal for some of the hardware to build and operate its cameras.
And when the rover finally launched in November 2011, Sumner played a key role in determining its landing site, pushing a recommendation for the Grand Canyon-esque Gale Crater.
“When you’re choosing to land on another planet, you’re going somewhere no one has ever gone before,” she says. “The most important thing is to be safe enough to land, because if you crash, you’re done.”
Sumner, along with her team, picked the crater for its topography and the answers it might hold.
“[It has] layers and layers of rock,” Sumner says. “And each layer holds a little bit of climate history.”
On paper, the job of planning the Curiosity’s travels might seem basic, mundane even. But each inch the rover moves proves critical.
“When it’s traveling, it takes pictures,” Sumner says. “There can be rocks and the rover can slip.” Even a few stray rocks or loose sand can cause huge, troublesome delays.
“You don’t want it to dig into the sand, [because] if it’s not moving forward when the wheels turn, then it stops—then the people on the ground have to try to figure it out.”
Once everyone’s patched into this afternoon’s conference call, it mostly sounds like technical jargon and minutia to the untrained ear.
“It’s like a foreign language, isn’t it?” Sumner says with a laugh.
As Sumner chats with the rest of the crew, her students listen and observe, Rivera-Hernandez occasionally pausing to point out key details from the Rover’s latest images, comparing them to findings from a previous mission.
“With some of the Mars Exploration rover, we had seen some sulfate veins, but not as extreme as we’ve seen at Gale Crater,” Rivera-Hernandez says. “At Gale Crater, we’d seen these veins everywhere and diversity—so it’s really a big deal.”
“Why are they so important?” Juarez Rivera asks.
“Because you need fluids. When we first found them … it was another piece of evidence that there had been moving fluids [on the planet].”
In short, because they contain tiny bits of life.
Ashwin R. Vasavada, the lead project scientist for the Curiosity rover, calls Sumner’s contributions crucial—not just for her extensive knowledge, but also for her efforts to expand the mission’s focus.
“After we landed on the surface, she continued to lead efforts from a fundamental geological viewpoint on how to better understand the story and history of Mars,” Vasavada explains on a call from his office at the Jet Propulsion Laboratory in Pasadena.
Sumner’s role has evolved in the decade they’ve worked together, Vasavada adds. She was initially brought in as a member of the mission’s instrument team, but her leadership, organization and foresight quickly placed her in an elite status.
“It’s a select group of people—there’s only about a dozen of them—who really become the scientific brain trust and help guide the entire team in a strategic way,” he says.
Back on earth, Sumner says the need to study this cold, rocky place that, for now, remains largely out of humankind’s reach touches on deeper universal questions.
“One of the really fundamental questions people of all cultures ask is what their place in the universe is,” Sumner says. “Knowing if there is life elsewhere is really important to understanding our place,” she says. “If we find evidence of life on Mars, it changes our view of ourselves: We are not alone.”Across the universe
Sumner picks up a sliver of ancient stone from a table inside UC Davis’ cramped, airless rock laboratory. The piece, excavated from a lake bed in the Antarctic, is thin and jagged in places.
“This one came by ship and arrived a month ago,” she says. “Now, we want to know what some of these complicated shapes look like in 3-D.”
This process involves gluing the rock to a glass slide and then using a grinding wheel to shave off of a thin layer. Next, the specimen will be polished and scanned in to create a digital version.
It’s mostly an undergraduate task, but Sumner still views the process with respect.
“It’s a very good entree into scientific research,” she says. “It’s how I got started. Some students don’t like doing this; they don’t like the interpretation part. It takes work involving the brain, and it’s a good way to sort out the students who like his kind of work.”
Sumner has always loved studying rocks, interpreting their stories.
The daughter of an artist and a physicist, her parents encouraged her to explore, to ask questions, to experiment. As a kid, Sumner says she knew she’d choose a scientific field of study, but it wasn’t until college that she found her path.
“I was always interested in the universe and astronomy. But when I was trying to decide which way to go, the field trips and looking at rocks and spending days outside drew me away from the more physics/astronomy side,” she says.
In a way, Sumner’s choice mirrored her childhood.
After her parents divorced, Sumner’s mother moved her and her younger brother to an Indian reservation. There, the preteen received a culture shock.
“I came from Bellingham, a college town with advance-placement classes, and ended up in a school where the first week of seventh grade there was a girl bragging in the back of the classroom about how she might be pregnant.”
To cope, Sumner set out to explore her surroundings. Her family’s house sat on 40 acres of land and she spent much time outside, alone. She now sees that as a good thing.
“I developed some internal self-confidence and alliances in myself,” she says. “I made choices to do things the way I thought they should be done, as opposed to the way peer pressure was pushing things.”
She carried that resilience to CalTech in Pasadena. There, drawn to the region’s diverse landscape, she enrolled in an introductory geology course.
“I had done a lot of backpacking and thought that was a great way to see Southern California. Then I took another geology class, because they had field trips to Baja California.”
A few classes evolved into a passion and doctoral study at the Massachusetts Institute of Technology. Later, an expedition to South Africa helped narrow the focus to rocks.
Eventually, Sumner’s work led her to the end of the world, or more specifically the bottom of the globe. She embarked on her first expedition to Antarctica in 2009, with the goal to study microbial rocks found in lake beds there.
Since then, Sumner’s returned four times with students. The journeys make for grueling two-month trips that usually transport a team first to New Zealand and then, after days of prep, via helicopter to a lakeside camp. Setup takes at least a week. And although there’s no real day or night, the explorers follow the region’s arc of natural light, working until the sun disappears behind a mountaintop and it becomes unbearably cold.
The real work, however, starts back in the labs, where Sumner and her students pore over details that hold clues to the early evolution of bacteria.
Specifically, Antarctica’s lakes could contain answers to Martian geography, she says. In the fall, Sumner and a student will study sediment deposited in the Antarctic lakes and how that might relate to other planets.
“We’ve found evidence of lakes [on Mars] and we don’t know if those lakes were covered in ice,” she says. “But if you have ice-covered lakes, then you’re isolating liquid water from the atmosphere. And it really changes the climate implications.”
Ultimately, she says, all these areas of study are linked.
“Some of the things we’ve seen in Antarctica [are] giving us ideas about something we might be able to find on Mars,” she says.
Those microbial rocks, for example. Like the one on her desk.
“It formed in the ancient ocean,” she says. “Looking at the living bacteria in it, the more specific connection is with Antarctica, with rocks formed by microbial communities in the lakes there [but] the connection to Mars is that this type of rock with a clear microbial signature is what we’re looking for there, for evidence of life.”
Such proof would obviously be a game changer.
“That’s where the real science starts,” she says.#GirlsWithToys
In May, Shrinivas Kulkarni, a male astronomy and planetary-science professor at the California Institute of Technology, gained notoriety for explaining to an NPR reporter that “many scientists, I think, secretly are what I call ’boys with toys.’”
Reaction was swift and viral: Female scientists and engineers around the world posted more than 17,000 pictures posing with an array of high-tech equipment and adding the hashtag #GirlsWithToys.
Sumner joined in by posting a picture of herself standing in front of a giant, planet-crawling robot: “#GirlsWithToys Me at JPL with the engineering twin of the @MarsCuriosity rover, which I help drive on Mars.”
Kulkarni’s sentiment, Sumner says, is hardly new. Sexism and exclusionary behavior and language have always been pervasive threads.
At CalTech, a lack of female professors—she remembers taking only one class with a woman, in literature—left an indelible mark.
Even now, she says, women in the science, technology, engineering and mathematics fields struggle to earn the kind of respect more easily bestowed upon their male counterparts. Studies on this subject, she says, have demonstrated a quantifiable bias.
Sumner’s hire at UC Davis made her the department’s third female professor. A fourth was hired soon after, and the resulting environment, she says, is “very different” than her own college experience.
Nonetheless, Sumner makes a point to mentor female students, whether advising them how to get the most out of study groups or guiding them through the oft-thorny world of feedback, reports and peer review.
Robert Zierenberg, a professor in geochemistry at UC Davis, says Sumner’s had a meaningful effect on young undergraduates, especially those who don’t initially see themselves as scientists.
“She provides absolutely great mentorship to people who might have come in with different educational backgrounds. And she convinces them, ’You can do this,’” he says. “She gets them excited and inspired.”
Frances Rivera-Hernandez, the Ph.D. student, is one such student.
“She’s affected me in thinking about how [I] want to be presented as a female in the sciences,” she says. “Traditionally, we’re brought up to think that we have to wear the makeup and wear the heels and be glamorous to be taken seriously. Working with her, I’m learning how to be professional without having to meet societal standards.”
For Marisol Juarez Rivera, Sumner’s mentorship goes beyond gender.
“I’m the first in my family to go to college. It’s kind of a weird transition being a grad student—my family has never been through this kind of experience,” says Juarez Rivera. “Dawn and I have talks about why it’s important for me to be a Chicana in STEM. She’s really encouraging.”
As an adviser, Sumner is also largely hands-off. Mostly that’s a good thing, her students say.
“She lets me be independent for research,” Juarez Rivera says. “My first year here, she was on sabbatical and not physically present, but she was still able to give guidance.”
Still, it’s the one area where Sumner says she know she too often comes up lacking. “Time is my biggest challenge,” she says.
There are weekly group meetings with graduate students, department-chair duties, the occasional geological expedition and, of course, the Curiosity rover mission. And when she’s not working, Sumner, who lives in Martinez and regularly takes the train to Davis, finds time for Capoeira dance lessons three times a week. She also collaborates on a video-art project with a friend. Sometimes, she even goes on vacation.
If she did have more time, Sumner says her dream work would take her back to Antarctica.
“There’s so many new ideas and new data to collect,” she says.
Besides, it’s decidedly easier to reach than Mars.
“It is like being on another planet, except you can breathe the air and your food is delivered.”
But what about Mars? Is she envious of that still-in-the-fantasy-stage citizen flight? What if she was given the opportunity for space travel?
“No. Absolutely not,” Sumner says.
For starters, she says, there’s plenty of reason to doubt the Mars One voyage.
“Since we first talked about it, it’s come out how badly that process is being run. Basically, it sounds like there is no way they will have the technology anywhere near ready. Which is not surprising.”
It’s not just skepticism, however, that keeps Sumner firmly grounded on Earth.
“I am not one of those people who is eager to explore just to explore,” she says. “I like doing things that are challenging, but I don’t like doing them just because they are challenging.”
It’s like Mount Rainier, she explains. Her father, an avid mountaineer, has offered to make the climb with his daughter. No thanks to that, too.
“I really enjoy being outdoors but I have no particular need to push myself physically to get to the top of a mountain. I’m not adrenaline motivated. I’m not physically motivated. I’m intellectually motivated.”