Scientist Pamela Conrad helps give Curiosity a daily to-do list to look for life's building blocks on Mars. In GSFC's continuing series of "Conversations With Goddard", Elizabeth Jarrell talks with Pamela about NASA's biggest Mars surface mission to date and how scientists are using the different payloads on Curiosity to search for signs of ancient life on Mars.

What do you do and what is most interesting about your role here at Goddard? How do you help support Goddard's mission?

I try to figure out what makes a planet habitable and, beyond that, if anything actually does live there. I'm presently focusing on Mars.

How do you test for habitability of a planet?

This is a complex problem that involves a lot of things, including asking questions about chemical composition and the physics of an environment. For example, you could have all the right chemical ingredients for life, but if it's too hot or too cold, then there probably won't be any life. You need the right materials and the right conditions at the same time to support life.

One of the problems associated with assessing a planet's ability to support life is deciding how often you have to do measurements in order to get the whole picture of what an environment is really like: what is the sampling rate? If the light fluctuates diurnally and seasonally, you have to measure it often enough to get an accurate picture of that fluctuation.

How do you find clues about what happened to a material millions of years ago?

We're developing a state-of-the-art laboratory here at Goddard to measure the isotopes of noble gases in various rock, mineral and water from the Earth and other places as delivered by meteorites. While other things can change, as various forces act upon these forces, these gases remain inert. The only thing that changes about them is the ratio of one to another or the ratio of different isotopes, the heavy and light versions of each of these gases. These give us clues about processes which happened over millions of years that are less ambiguous than other processes you can study about natural materials such as rocks, atmosphere and sea water.

Once material is created, what happens to it over billions of years? We have a discrete set of raw materials in the universe that make up life. Stars, planets, people, microbes and even dust are all made out of a finite set of chemical elements. How these things move through time and space determines whether an atom will end up in a star or a microbe.

What interests you the most about your work?

Any time you conduct a scientific investigation, you are forming a model as you get data. And models aren't perfect, so they only work to a certain extent. If the initial assumptions are incorrect or change, the model stops working. So we try to come up with new models that are consistent with the things we observe and measure.

I tend to think of everything both in terms of space and time because everything that happens involves space and time. Models are also limited in their extent. Here is where it gets hard to think about. Models are not just limited by space and by time, they are also limited by the extremes of our assumptions. An example of this would be how many different chemicals are in a particular environment.

If you only have six chemicals, you work with these six chemicals which become your universe. If you have 100 chemicals, it becomes many times more complicated. Wrapping your brain around all the combinations of the chemicals, and all the combination of other physical factors like temperature, radiation and how fast those things change, gives you a really complex universe to contemplate.

Figuring out what ingredients and conditions facilitate the formation and maintenance of life is a really complicated problem and chemistry is not enough to characterize an environment's habitability potential. That's why I have to take an interdisciplinary approach.

Do you think that we will find an environment that could support life?

Yes. We do not all agree on what makes an environment habitable. I think that there are lots of factors involved. Figuring out that list of factors is very important.

It's very clean! And organized!

What is your involvement with the Sample Analysis at Mars instrument suite?

SAM is the most complicated science instrument ever sent to another planet, in this case, Mars. SAM is in the belly of Curiosity, the Mars rover. SAM measures the chemistry of gases. Sam can breathe in air. If what we want to measure isn't a gas, SAM can bake rocks in one of two ovens until they become a gas and then measure it. Light chemicals are driven off upon heating, which is why your food smells when heated. That's how we measure gases on Mars.

There is a history of baking rocks on Mars. Viking did this in the mid-1970s. But Curiosity is the first MARS rover that can drill inside rock and deliver it to analytical instruments. We couldn't bring home the bacon, but we could certainly fry it in the pan.

I have a couple of roles. For our team in specific, I'm in charge of operations. The science I work on has to do with understanding the isotopes of the inert gases krypton and xenon that SAM measures in the atmosphere of Mars. For the broader mission, I rotate through leading the science operations working group a few days a month.

This is the group that tactically decides what to do on Mars for that day and it generates plans to send to rover to execute that science. We have a strict time limitation caused by the position of Earth and Mars, so we only have a small period of time every day within which to send instructions. We give Curiosity a to-do list every day, and every day we also receive back data based on that list.

How do you communicate new discoveries from Curiosity?

We try to be as transparent as possible and use words that are understandable to those who don't have a specialized education. We are accountable to every single citizen as taxpayers. We are also accountable to the entire world because we build on discoveries. Someone will take what we learn and use that information to build the next thing. This is how we evolve our science and technology.

What do you think will be Curiosity's legacy?

Curiosity rover is bringing back information about the chemistry, physics, weather, geology and mineralogy of Mars, our nearest planetary neighbor. This information helps us understand a broader picture of the processes that have affected Mars. In understanding those processes, we hope to understand how common it is that a planet can evolve into conditions that can support life.

Curiosity also offers a lesson in what a good, very large team based all over the world can do when working cooperatively towards a common goal. On any given day, we have many, many people working as a team. The composition changes daily. No one person can work this intensively every day. We have team members from all over the world and we rotate in and out nearly seamlessly. Every single day, for two years, this humongous team has worked very well together to send instructions to a robot millions of miles away. I am proud to be a part of it. Were you involved in fieldwork?

Yes, in order to understand the environments of other planets, I spent about 13 years exploring extreme environments on this planet. I've been to the Arctic, the Antarctic, the very bottom of the Pacific Ocean, Death Valley and lots of alpine deserts. One must prepare for robotic exploration by first exploring in the flesh so that the approach can be defined and we can tell the rover what measurements are needed.

Why did you become a scientist?

I initially was a singer and composer. I had a media production company that produced videos about medical education and science. One day I was on a shoot and it was raining, so I cut through the geology building on the campus of George Washington University to keep the equipment dry. We walked right by a giant showcase of beautiful minerals and crystals. Looking at those rocks, I made the decision right there to go to school to become a scientist. I thought that I would have more fun doing science than making videos about someone else doing science.

School took me 12 years. My undergraduate degree was in music, so I had to go back for all the science credits. I now have a doctorate in mineral physics, a specialty of geology.

Why are public engagement activities so important?

I am also involved with a lot of public engagement activities. Working with students and the public is an important responsibility. Everyone who has the good fortune to be doing something as amazing and fun as space exploration should take seriously our relationship with the public. We get to work at one of the coolest places on this world and virtually off of it. It's important to recognize that we have something very cool to share with the citizens who pay for it.

When I was 14, I received a medal as an award for a science fair from NASA at a ceremony at Goddard. The medal is the size of a coin and engraved with my name. I take this medal with me whenever I go somewhere especially challenging. It was in my pocket when I went to the bottom of the Pacific Ocean.

My point is that education and public outreach efforts are important. They pay off later. Here I am - on Mars.

In your past life, what kind of singing did you do?

I was an opera singer. I trained locally and also in New York with Sebastian Engelberg, who was a very well-known singer and teacher at Mannes Conservatory. My favorite role was Cherubino from Mozart's "The Marriage of Figaro." It's a very comical role. I also sing other styles of music including rock, jazz and acoustic. Right now I mostly sing in the car; I'm pretty busy with Mars!