Emily Stewart Lakdawalla '96

Emily Stewart Lakdawalla ’96 might have the unusual job title of any Amherst alum: planetary evangelist. That’s her role at The Planetary Society, the Carl-Sagan-founded, Bill-Nye-run, California-based nonprofit that advocates for space research and exploration. A geology major at Amherst, Lakdawalla graduated summa cum laude and went on to receive a master’s degree in planetary geology from Brown. Today, she lives in Los Angeles with her husband, economist Darius Lakdawalla ’95, and their two daughters. In addition to her work for The Planetary Society (where the other half of her job title is senior editor) she’s the author of the 2018 book The Design and Engineering of Curiosity: How the Mars Rover Performs Its Job (Springer Publishing). Lakdawalla spoke with her senior thesis adviser, Tekla Harms, the Massachusetts Professor in Chemistry and Natural History (Geology), about the work of the Curiosity rover, the potential for life on Mars, the limits of human understanding and more.

Book cover of "The Design and Engineering of Curiosity: How the Mars Rover Performs Its Job"
When NASA first sent Curiosity to Mars, what did it hope to learn?

Curiosity is the culmination of 20 years of Mars exploration. Scientists knew there had probably been water on Mars in the past. We did not know whether water on Mars had been a transient thing, or if Mars had once been Earth-like: Was there water that lasted a really long time, creating habitable environments where little bugs might have originated and thrived? Curiosity answered that question about a year into the mission, affirmatively, yes. Now the mission is all about characterizing how long there was water, what the climate was like when water existed, the kinds of environments that were there, the scope of places where life could have once lived.

Is it fair to say that Curiosity is a robotic geologist?

Absolutely. John Grotzinger, the project scientist [from 2007 to 2015], realized it wasn’t enough to have planetary geologists looking at satellite images. This robot is a field geologist, and so, to get good science, you’d need to involve people with experience doing Precambrian field geology on Earth—people who understood the environments that existed before there was land life on Earth. Grotzinger’s daughter is now a geology major at Amherst, so we’re closing the circle on that one.

There are 10 scientific instruments onboard Curiosity. Pick one of them and explain what it does and why it’s important.

It’s hard to choose between the two that are Curiosity’s heart and soul.

I’ll give you two.

I’ll start with the CheMin, an instrument that determines and measures the minerals present in a rock. As any geologist will tell you, minerals are key to understanding the history of rock: how it formed, the temperatures that existed, what’s happened since it formed, whether the minerals got altered by water. This is a standard piece of equipment used by geologists on Earth: you get a sample, crush it into a powder, put it in your machine. The crazy thing is, at UMass that instrument—is it still the size of a refrigerator?

Yes. They’re getting smaller, but why make it small if you don’t need to?

Exactly. CheMin on Curiosity could not be the size of a refrigerator. It’s about the size of a toaster—and that’s probably mind-boggling to any geologist who has ever worked with a similar machine. It’s a fairly straightforward instrument—put powder in, get mineralogy out—so, really, the challenge was getting it to Mars in the first place.

What have we learned from CheMin?

We’ve learned that the rocks at Curiosity’s landing site contain a lot of clay. Clay forms when you take the more common minerals in volcanoes and attack them with water. These rocks were exposed to water for long enough to fundamentally change their nature—and that change took place in a moderate-temperature, moderate-pH place where Earth life would probably be fairly happy. CheMin has done other cool things, too, including the first rock dating on the surface of Mars. Some of the minerals are 4 billion years old (give or take 600 million), which tells you the rocks could be nearly as old as the solar system.

What does the second instrument do?

It’s called SAM, for Sample Analysis at Mars. It’s a gas chromatograph mass spectrometer with a tunable laser spectrometer, and it looks for organic materials in the rocks. I want to be careful when I talk about organic materials, because a lot of people hear organic and think life. If they found organics, that means they found life. No, that’s not how it works. Organic chemicals are any molecules that have carbon in them. Organic materials form naturally in the solar system, without requiring life. If you can find them preserved in ancient rocks, that tells you that the environment that existed when those rocks were formed was one that did not bust up organic materials, did not oxidize them, did not break them down. Give them enough time, happenstance and who knows what else—they could become life. SAM has proved that Mars had those conditions.

This mission is at the limit of what humans are capable of doing remotely—and even, possibly, beyond that limit.

I want to clarify something: You don’t work, nor have you ever worked, at NASA, right?

That is correct.

How did you gain entry into all of this information?

I love this question, because it allows me to talk about how NASA is one of the most open federal agencies out there. NASA has a mandate to share all of its information with the public, so all the data that comes back from space missions is generally made public within six months, on average, of its acquisition, after it’s been validated.

I’m now going to ask some philosophical questions. The first is: In writing the book, what did you learn that isn’t specifically about Curiosity?

I learned that this mission is at the limit of what humans are capable of doing remotely—and even, possibly, beyond that limit. Sometimes you create an entity so complex that humans are incapable of understanding everything it does and can do, and therefore how to operate it most efficiently. I could be talking here about a space rover, but I could also be talking about a government. The current project scientist, Ashwin Vasavada, told me that this rover has emergent behaviors that are impossible to predict, so the operation of it is always a response to what you couldn’t imagine happening. And so you have to guide your complicated machine with knowledge and understanding, but also with pragmatism. You have to be willing to accept a certain level of nonfunctioning or nonefficient functioning just for the whole machine to move forward. I think that’s true of any complex entity.

What you’re describing makes me think of the many complicated systems that interact to make Earth the planet that it is, and the unintended consequences that arise when people tweak those systems.

It’s an argument for doing the best you can to understand the system, but also for not sitting back and waiting until you understand it perfectly. It sounds too simple, but you have to do the best you can with what you’ve got. And move forward somehow.

Tell me about the people who conceived and built the mission. What did it take for them to do this remarkable thing?

First of all, they had to imagine how to do something that nobody’s ever done before. I think there’s not enough attention paid to how creative a process that is. There’s also an immense amount of creativity involved in imagining the different ways things can go wrong. Rocket engineers have a saying on launch day: There are a thousand things that can happen, and only one of them is good. These engineers have had many moments at 3 a.m. in bed saying, “Oh, my God, I hadn’t thought of this before. I’ve got to go write it down and make sure the rover doesn’t fail in this ridiculous way.” Engineers and scientists on space missions—they tend to be artists, thespians and poets, and I wish there wasn’t such a strong demarcation between STEM fields and arts fields, because both are extremely important. When high school students ask me what they need to do in order to be an engineer or a scientist, I tell them, “Well, you’re asking me that question because you love engineering and science, but do not skimp on English or history or acting.”

The engineers and scientists on space missions—they tend to be artists, thespians and poets.

I’m going to quote you when I go into my next advising session with my students. It’s sometimes hard for them to understand that the arts are of value in a research team, not just the nuts-and-bolts technology.

It’s a harmful stereotype that scientists are lone operators working late at night by their telescopes or at their lab benches. That’s not how it works. Science is conducted in large teams, and having the ability to work in a team and make the most of your team members’ individual skills and capabilities, to communicate your ideas to others, to communicate your goals to grant funders—all of that is immensely important.

How did you become this expert communicator who translates complex science to nonscientists? What were, in retrospect, the critical career decisions you made?

I’m often asked to give career advice, but my path was circuitous and I’m not sure it’s the best model. After Amherst, I felt like any door I walked through, I would be shutting all the rest of them. I felt a sense of loss, that I was losing my potential, my possibilities. But that wasn’t what I was losing: once you’re done with college, you want assurance that you’re taking the right path, but that assurance no longer exists. After grad school, I followed my husband to Los Angeles and got a job in an environmental consulting company. I knew that I probably didn’t want to stay in that field, and I was right. I didn’t like the corporate environment. But I learned a lot about city planning, and that’s benefiting me as a homeowner to this day. I also learned how to surf. And I honed my writing ability. The good news is that there are no wrong paths.

There’s a theme between Curiosity’s success and the advice you’ve just given, which is to embrace and manage uncertainty, and to move on in the face of it.

And keep yourself healthy. Space is a field that inspires a lot of passion in the people who go into it. My job title is planetary evangelist: I go out and give talks about how amazing all these worlds are and the excitement of traveling through the eyes of these robots, seeing strange new worlds. It’s common for fields that inspire that much passion to exact a lot out of the people who are in them. It’s important to not let anybody say that you should be paid in passion. No, you should be paid in money and benefits. You deserve that, and you deserve health, and you deserve a stable life for your family. Make sure to advocate for yourself as well.

Tekla Harms teaches the geology department’s introductory course almost every semester. She also teaches courses on structural geology and tectonics and takes students on research trips around the world, where they study the evolution of mountain belts and the interactions of plate boundaries in creating those belts.

This article is adapted from an Amherst Reads interview. Listen to the full Q&A at

Photo Credit: Isabel Lawrence

Marvelous Mars

A photo of Mars' surface with mountains and canyons

Lakdawalla processed all of these images from spacecraft data. The photo above, taken by the Mars Hand Lens Imager (MAHLI), shows where Curiosity drilled into an area known as Windjana. “Note the cascades of fine sand that have slumped due to the percussive activity of the drill,” reads the Planetary Society caption. As explained on the NASA website, MAHLI is a self-focusing camera, roughly 1.5 inches wide, that “provides earthbound scientists with close-up views of the minerals, textures and structures in Martian rocks and the surface layer of rocky debris and dust.”

Photo by NASA/JPL/MSSS/Emily Lakdawalla

The red surface of Mars with mountains in the distance

Above, Curiosity’s Mastcam-34 camera took this “three-image panorama of a gap between two headlands,” according to the Planetary Society caption. Below, a triple-terraced crater. As Shane Byrne writes on the High Resolution Imaging Science Experiment website, the image reveals different material strengths, “probably caused by layers of ice (weak) and rock (strong).”

Above photo by NASA/JPL/MSSS/Emily Lakdawalla; Below photo by NASA/JPL/UA/Emily Lakdawalla

A triple-tiered impact crater

An asteroid in space

Mars Express, a mission of the European Space Agency, captured this image of Phobos, the larger of Mars’ two moons, on Jan. 3, 2007. To quote the Planetary Society caption, “The view peeks slightly over the north pole (which is located just above the top of the prominent crater on the terminator near the top of this image).”

Photo by ESA/DLR/Fu Berlin (G. Neukum)/Emily Lakdawalla