Dr. Delia Santiago-Materese

Dr. Delia Santiago-Materese wants things to get complex

From terrestrial animals to experiments in microgravity and Martian clouds, this NASA program scientist’s career path links diverse challenges. Today, she supports a mission to Saturn’s moon Titan, a world teeming with organic molecules that could hold valuable clues about the origin of life.

When novelty is your hobby, you already have a large part of the recipe for a career full of challenges. That is why Dr. Delia Santiago-Materese describes her path within NASA as “meandering.” Her diverse roles have taken her to low Earth orbit, to the clouds of Mars, and to the surroundings of Jupiter. Now, they are also bringing her closer to the surface of Titan, an intriguing moon of Saturn. Woven together by her exploring spirit and a perennial curiosity, all these experiences have one point in common: life.

Today, Santiago-Materese is part of the Planetary Science Division at NASA Headquarters in Washington. The main decoration in her office is a model of Jupiter, larger than a basketball, resting next to a scale model of the spacecraft exploring it, Juno. Small black and red pins with the inscription “Dragonfly” rest in the center of a round table. Several framed diplomas cover a wall. From here, Santiago-Materese does “a little bit of everything” on any given workday as a program scientist for the Juno and Dragonfly missions, and for the Discovery program, which features a portfolio of several missions in our cosmic neighborhood.

This medley of roles is no coincidence. Santiago-Materese describes herself as someone who does not pursue a single goal, but rather diverse interests that she discovers along the way. “I am always looking for something new to add to my experiences,” she says, “because I think I also get bored easily.”

The daughter of a military family, Santiago-Materese was born in Spain by coincidence. Her roots are actually on another continent: her mother is Mexican-American and her father is Puerto Rican. From her time in Spain, she only keeps some baby photos; she lived part of her life in Texas and then in California, which she considers her home—despite having spent her childhood summers in San Sebastián, Puerto Rico. It was in the Golden State where she first imagined herself as a veterinarian and decided to study Biological Sciences. And it was during her studies at Stanford University, “just around the corner” from NASA’s Ames Research Center in California’s Silicon Valley, that Santiago-Materese discovered astrobiology.

This elective course brought her closer to a discipline that, to some extent, was in its infancy. Today, NASA’s Astrobiology Program investigates life in the universe on many levels: how it began, how it evolved here on Earth, and where it might exist elsewhere. And that was how Santiago-Materese realized that biology and space were not two isolated things, she recounts.

Rodents, Insects, and Martian Clouds

After finishing her studies, Santiago-Materese completed a one-year internship at the San Francisco Zoo. But the unknown that astrobiology presents continued to intrigue her, so she went back to one of her professors to inquire more about it. She asked around and found someone at Lockheed Martin, a company that often contracts with NASA on space projects. They were looking for people for a new project studying the nutrition of the food bars for rodents traveling to space aboard the space shuttle.

Santiago-Materese has applied that formula ever since: identifying what truly interests her and finding the right person to ask questions. If people “don’t know what you’re interested in, they can’t help you,” she explains. After experience with the Space Shuttle Program, including managing databases for science payloads aboard the space shuttle, she went on to work with the International Space Station, which was then beginning its legacy of over 25 years in Earth orbit. She supported the development of biological experiments in microgravity, this time with fruit flies. But Santiago-Materese wanted to keep moving farther from Earth and investigate future space destinations.

This curiosity led her to the Martian sky. As part of her graduate studies at the University of California, Santa Cruz, Santiago-Materese investigated the Martian atmosphere, focusing on ice in the clouds and the development of climate models for the Red Planet. She earned her master’s degree and would later return to complete her doctorate under the NASA Pathways program, which is one of the agency’s primary early-career hiring pathways. She would defend her thesis six months after giving birth to her first daughter (one of the achievements she is most proud of, she says). That is why, although she loves the “weird” planets of the outer solar system, she is “more of a Mars person,” by training.

At NASA Ames, Santiago-Materese held various roles, ranging from social media and open science to lunar sciences. She then became a program officer for the Solar System Workings program in the Planetary Science Division at NASA Headquarters as part of a detail, or temporary assignment. And then, she took off for Maryland along with her family.

Enabling Science

Santiago-Materese sums up her current role as a program scientist as the “science liaison” between NASA Headquarters and a mission. “When you do program scientist work, you might not be specialized or an expert in the exact science, but you need to be able to understand it and talk about it, to understand its importance,” she explains. “In general, we are supporting other people so they can do science.” In this endeavor, being someone who “gets more energy from working with people” is useful… and necessary: “You are having conversations all day long” with colleagues from different disciplines— from science and engineering to finance.

The Juno mission, in orbit around Jupiter since 2016, and Dragonfly, which is scheduled to launch no earlier than July 2028, are part of NASA’s New Frontiers program. Santiago-Materese also oversees the array of missions in the Discovery program, which includes ongoing science missions like Psyche and Lucy—heading to different asteroids—and future missions to Venus.

For Santiago-Materese, sharing her unconventional path can be valuable for students and youth in general, especially those who are unsure of what they want to do. “Your dream job,” she says, “you might not know it exists, or maybe it doesn’t exist today.” Beyond that, this zigzagging path has led her to accumulate experiences and relationships with different people, which she treasures even as she sets off for her next destination.

An Alien World

About two years out from Dragonfly’s launch, it is no surprise that this robotic mission takes up much of Santiago-Materese’s time. “Dragonfly feels like a combination of all my different experiences over time,” she reflects. And it signifies, to some extent, a return to her roots: it is an astrobiology mission. Although not designed to detect life, Dragonfly will investigate prebiotic chemistry: the chemical processes that could have led to the emergence of life on Earth.

Dragonfly will embark on a journey of about six years to the surface of Titan. The spacecraft will carry an array of science instruments and will be the first NASA science mission to explore another world by flying from location to location. This car-sized rotorcraft will touch down at various geological sites of interest to analyze the moon’s composition and its habitability potential.

When it arrives at Titan, it will encounter a landscape that is strange and familiar at the same time: it could be a window into Earth’s remote past. This frozen world has a thick atmosphere and clouds drifting across the sky; dunes, lakes, rivers, canyons and mountains. Titan even has a process equivalent to our water cycle. However, on Titan, it is not water that flows but hydrocarbons, primarily methane and ethane. “It’s a more methane-based chemistry, so it is very alien, and that is what I really love about Titan,” says Santiago-Materese. And on this moon, organic molecules abound.

These molecules contain carbon and are used by all known forms of life. They are fundamental to understanding the origin of life, as they can be produced by both biological and non-biological processes. On Titan, these organic molecules fall to the surface and form dense deposits over its bedrock of water ice. Scientists believe that the complex chemistry precursor to life could be triggered there if provided with a little liquid water, such as that generated by an asteroid impact.

Santiago-Materese is especially excited about what the Dragonfly Mass Spectrometer (DraMS) instrument will help discover. DraMS, designed and built at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, will analyze samples from Titan’s surface. “The more complex things get, the more interesting things happen,” she says. “So I’m curious: just how complex do the molecules get? Will we find any interesting patterns?”

But in science, every time you ask a question, a new one arises. Dragonfly will try to answer several of them. “When you have a planet with complex chemistry but not life, what happens? What is there before life?” the program scientist wonders.

Titan, a valuable natural laboratory, “is going to completely change our understanding of what another world can be like,” she anticipates. In addition to what the scientific community expects to discover thanks to Dragonfly, Santiago-Materese is interested in the potential unexpected findings. “There are very defined science goals, but a lot of it is exploratory work,” she explains. “It is kind of nice to know that there is a big range [of possibilities], that we could be very surprised.”

By Noelia González, NASA’s Goddard Space Flight Center, Greenbelt, Maryland

Lee esta historia en español aquí.