By KATHERINE QUINN
At the age of 25, not many people can say they are on track to receive a doctorate degree within a year. Fewer can say they are concurrently employed at NASA. And fewer still can say they discovered the evidence of water on Mars.
Mary Beth Wilhelm ’12 is a Ph.D. candidate in Geological and Planetary Sciences at Georgia Institute of Technology and a planetary scientist working for NASA’s Ames Research Center in Mountain View, California. In April, she and fellow scientists affiliated with NASA Ames published a paper of their discovery of hydrated salts on Mars, signifying the presence of contemporary water activity on the surface. The discovery was based on orbital data from the Mars Reconnaissance Orbiter and was confirmed by NASA this September.
Mary Beth Wilhelm ’12
Water is an essential component of life and its discovery on Mars could have wide-reaching implications for future explorations and the potential habitability of Mars. For Wilhelm, this possibility drives her research interest, and her Ph.D. thesis is focused on looking for not-so-obvious remains of life in essentially barren landscapes and extending these findings to the possibility of life on Mars. Specifically, she analyzes soil samples from Mars-like environments to research the degradation of biosignatures, or substances providing evidence of past or present life.
When she’s not in the United States, Wilhelm can be found conducting field work in the Yungay Region of the Chilean Atacama Desert, covered head-to-toe in a clean suit, collecting soil samples for testing. This desert and Antarctic Dry Valleys, some of the oldest and driest regions on Earth, are two of the best terrestrial Mars analog environments.
What makes a desert on Earth analogous to the surface of Mars, exactly?
There is a strong background of knowledge and ongoing research into the properties of the Atacama, and Wilhelm cites Prof. Terry Jordan, earth and atmospheric sciences, as contributing to this area of research by studying soil properties. One of the important qualities of the Atacama is its ability to preserve dryness and to not only suspend hydration but also suspend microbial activity, which degrades biomarkers.
“The soil is too dry to support terrestrial life but by looking at the dust blown into the desert, we can find evidence of ancient ecosystems,” she said.
This research is also essential to Wilhelm’s work at NASA because as NASA plans to do more sample returns from Mars, analyzing analog samples collected from Atacama can help determine which samples would most likely have biomarkers and decide which samples should be collected.
In order to research the possibility of life on Mars, Wilhelm gathers data from biomarkers in soil samples of Mars-like environments, such as the Atacama Desert in Chile.
Wilhelm’s research and work with the Mars Science Laboratory interpreting orbital data contributed to the finding of hydrated salts on Mars. The Compact Reconnaisance Imaging Spectrometer for Mars (CRISM) aboard the Mars Reconnaissance Orbiter used infrared detectors to collect data and return the soil spectra. This gave clues as to the soil composition and chemical signature of the material on Mars’s surface.
In analyzing their findings, Wilhelm and her collaborators found tiny changing features that were indicative of hydration signature, appearing and disappearing in the data. The alternating appearance of these hydration signatures shows the presence of some kind of cycling water system on Mars and implies the presence of liquid water.
“At the low temperature and pressure conditions on Mars, salt extends water stability,” Wilhelm said.
The findings are novel and intriguing not only due to the relative scarcity of liquid water in our solar system, but for future study and exploration of Mars. Wilhelm said this discovery is important for two main reasons: liquid water is one of the essential components of potential habitability and having a liquid water source will benefit explorers and improve the safety of future expeditions. This is a big step in the right direction for Wilhelm: “[It’s] a new puzzle piece to add to the stories of habitability on Mars.”
The testbed version of the Sample Analysis at Mars machine aboard the rover Curiosity, which is looking for organic material on Mars.
For Wilhelm, thinking about outer space and the red planet in particular has been a lifelong passion.
“Since I was little, I have always been interested in science and astronomy. I have always been a Martian,” she said.
Growing up in the Bay Area, she took advantage of nearby opportunities and began an internship at NASA Ames research center in Mountain View in 2006. Even nine years ago, her first projects related to Mars and involved studying the presence of gullies, or networks of narrow channels on the steep slopes of the planet.
After entering Cornell she was able to continue working for Ames over breaks. But since her first day of classes, she began pursuing research opportunities and worked in astronomy, astrobiology and geology before she graduated. She was also the science team project manager in engineering project team Violet Satellite.
For Wilhelm, taking advantage of research opportunities made her undergraduate experience remarkable: “Everyone was so brilliant, it was an inspiring place to be.”
Wilhelm remembers her time at Cornell as fundamental to developing her skills as a researcher and a scientist.
“The more research you do, the better you get at it,” she said. Her early research experience taught her to ask more questions and helped develop the ability to work in an interdisciplinary capacity, skills she draws on today with her research team.
Currently, Wilhelm plans to wrap up her Ph.D. in the coming year and later start her own lab at NASA Ames. For now though, she is still enjoying the enthusiastic response to the discovery, from science publications the show “The View,” which Wilhelm was watching when the hosts began talking about Mars.
“Suddenly, Whoopi Goldberg was talking about water on Mars. Whoopi Goldberg was talking about something I had done,” she said.
Wilhelm shares a passion for science communication and wrote Mars-related science blogs for KQED, a public media company based in San Francisco. She recently visited her old elementary school to present on the discovery and was thrilled to see young students so excited by the topic.
Wilhelm said she appreciates that one of the important qualities about planetary science is that advances in the field are not only interesting to scientists in this field, but just as exciting and tantalizing to outsiders.
Even in the ever-connected digital age, a push for science communication and coverage is just as important as ever.
“It is so important to reach young people and get them interested in science,” Wilhelm says. “Even if they’re first inspired by planetary science, this could be a gateway into studies in any STEM field.”
Wilhelm said hopes discoveries like these will inspire young people to explore science fields and find a love like she did. “Stay curious,” Wilhelm said. “Find what you’re passionate about and follow it.”