Johnson studies the early evolution of the surface environment on Mars. Currently she is a Junior Fellow at Harvard University, where she is poring over data returned from the new Mars rover, named “Curiosity.” (She worked at mission control for the last two Mars rovers, named Spirit and Opportunity.) Recently she was in the Australian outback, collecting data from sites that are geologically similar to the site (called the Gale Crater) where Curiosity landed on Aug. 6.
“A dominant theory for Mars is that a billion-year period of warm, wet conditions was followed by a billion-year period of arid, acidic conditions,” she says. “The geology in Gale Crater is especially intriguing because it contains layers that formed under each of these climatic conditions, yet the layers alternate.”
Johnson’s interest in the solar system began in her childhood, during stargazing expeditions with her father, an amateur astronomer. As an undergraduate at Washington University in St. Louis, she majored in environmental studies and mathematics and did research in planetary science. At MIT, she focused her research on the early life of planets, seeking to discover factors that played into the development of cosmic bodies such as Mars.
“It’s such an open field,” she says. “We know so little, when you come down to it, about how these other worlds come together. So in order to build hypotheses, you have to synthesize a lot of information. You have to go to geology, physics, chemistry, all these different fields, to put together how a planet works.”
In 2008, her final year in the Department of Earth, Atmospheric and Planetary Science at MIT, Johnson received the Hugh Hampton Young Fellowship, a graduate fellowship that supports students whose work crosses disciplinary boundaries. She found that it gave her the freedom to explore sides of her passion that she would otherwise have missed. “Usually the final year of graduate school is all-encompassing — you have to work on your thesis, do other research, go on the job market, and in addition to that you have to work,” she says. “This gave me the time to do extra things I would not have been able to do otherwise.” Long interested in issues of climate and planetary change on Earth, she joined the Energy and Environment Advisory Committee for the 2008 Obama campaign.
The effects of this side pursuit were far-reaching. When Obama won the election, her volunteer work led to a position as a policy analyst with the White House Office of Science and Technology Policy. Working for the President’s Science Advisor, she used her experience with planetary issues to research the policy implications of environmental problems ranging from greenhouse gases to the recent BP oil spill. The position lasted from 2009 until 2011.
Now back in academia, Johnson says she will likely parlay her interests into a career as a professional researcher at a university. But her time in public service gave her a different sense of her future career path than she would have had otherwise, she says. In Washington, she found role models in scholars who had embraced dual vocations, combining careers in academia with two-year stints serving the government and advising on matters of national importance.
“Usually the people you see doing that are economists and social scientists; scientists do it less often,” she says. “But in Washington, I saw a few of them who were research scientists, and it showed me that there was a model for us, too. I’d love to do that — to work at the cutting edge of research, and then help apply that to figuring out national policies that relate to scientific matters, or that affect scientific communities and researchers.”
“It made me feel bold enough to dream of a future that’s a little different from the standard,” she adds.
Johnson praised MIT’s emphasis on intellectual diversity.
“My advisor, Maria Zuber, gave me so much intellectual freedom in carving out the questions I wanted to ask,” she says. “They were big questions, so I had to learn about a lot of different things in order to put together an answer.”
To current students at MIT who want to pursue interdisciplinary interests, she says: “Find mentors and role models. A lot of people embrace that idea at MIT. Find them, talk to them.”
For now, she is going over geological research data in Cambridge and celebrating the recent birth of her first child. Over the next few years, each, in their own way, will be exploring new worlds.