Sara Imari Walker is a theoretical physicist and astrobiologist who researches the origins of life, physics of life, and artificial life. Before joining the Zócalo/Experience ASU event “How Should We Prepare for Aliens to Arrive on Earth?,” she joined us in the green room to talk about the physics of time, seeing an active volcano, and her fascination with Saturn’s largest moon, Titan.
What did you want to be growing up?
My mom's an interior decorator, my dad's a hairstylist, and I just grew up in a very creative household. So when I was a teenager, I really wanted to do something in the art space. And I liked pastels a lot, because I like pushing the colors around the paper. I still feel like doing science is doing that, but with mental models instead of pastels.
Do you have a favorite science fiction story?
I love “Story of Your Life” by Ted Chiang. I think because I focus my study on alien life, I always like alien encounter stories. But that one in particular is really exciting for me because it's playing with concepts of time.
What is your hidden talent?
I like to run. I live in the mountains in the desert, and I like running in the mountains—that's one of my favorite things to do. It saved me during the pandemic, because I could just run out my back door and then run up into the [McDowell] mountains. That was like my therapy.
What's the most beautiful place on Earth?
I once saw an active volcano. I was in Iceland, and it's so weird, because [you’re] walking on this ridge, and the volcano was on the left side and ocean was on the right side, and you keep hearing something you think is the ocean waves, but it was actually the rock sloshing back and forth. It was just such a visceral experience. We live on a really amazing planet.
What's your favorite TV show at the moment?
I really like My Next Guest Needs No Introduction With David Letterman. I love conversations. And I love deep dives into how people think. He's got all these celebrity guests on and you find out all these things.
What celestial object do you relate to the most?
Titan [Saturn’s largest moon]. I think it might be alive. But it's hard to recognize that, and I think it kind of represents the inner potential of the creativity and purpose that we associate with life. Titan’s kind of like this hidden variable in the solar system, because if it's alive it's totally different than anything we've encountered so far. So it’s just sitting there mysterious.
When do you think humans will first encounter extraterrestrial life?
Oh, I think we're gonna make it. What I mean is, I don't think that we understand life enough to recognize it. And I think we have to do the experiments to evolve life in the lab from scratch, basically making aliens before we know what they look like.