Sara García Alonso: "I had to survive a night bivouacking, buried in snow at -15°C."

BarcelonaIt's cool in Barcelona and drizzling a little. And yet, the queue keeps growing. Well before the event's scheduled start time, it already stretches beyond the corner of the Casa Seat building, at the intersection of Diagonal and Passeig de Gràcia, and continues up the street. Waiting patiently and impatiently are many children, young adults, parents, grandparents, curious people, and above all, science enthusiasts. Some—the little ones—are even dressed up for the occasion. This afternoon they will meet their heroine, the molecular biologist and astronaut Sara García Alonso (León, 1989), who is coming to the presentation of her first book, Orbits (Ediciones B, 2025), with her Mars-red hair.

Inspiring, García Alonso defends that we must pursue dreams, that mistakes are crucial for learning, and that science and research are the basic pillars for moving towards a better society. Astro Sara, as she is known, is the first Spanish woman selected for the European Space Agency (ESA) astronaut reserve. With a PhD in molecular biology, she combines this work with her research at the Spanish National Cancer Research Centre (CNIO) on cancer and precision oncology and scientific outreach.

What does an astronaut's job entail?

— A career astronaut, like Pablo Álvarez, the other Spaniard selected, is ESA personnel and is constantly training, preparing for a mission or participating in Agency-related projects, such as space flights coordinated by international agencies: ESA, NASA, Roscosmos, and the Canadian agency. Those of us in reserve, on the other hand, keep our current jobs. Should a mission arise, a specific contract would be activated for us.

What kind of mission can they perform?

— NASA, for example, offers opportunities for what it calls PAM, or Private Astronaut Mission, lasting 15 days. During this time, reserve or non-professional astronauts go to the ISS to conduct science, disseminate knowledge, and test a technology. In this case, as is also the case with scientific projects, especially those that receive public funding, a period is opened for receiving applications, and then the experiments that will ultimately be carried out are chosen. They are chosen based on their level of preparation, implementation, and reliability, as well as their feasibility, the resources they require, and their impact. The Spanish government, for example, has already launched a plan to fund microgravity-related projects on the ISS. These are the types of projects I would undertake on a mission.

At the CNIO, you're researching new therapeutic strategies for lung and pancreatic tumors caused by the KRAS oncogene. However, when you learned that ESA was looking for female astronauts to travel to Mars, you decided to apply. Why did you?

— As a child and as an adult, I had fantasized about joining NASA because it's in these kinds of centers where the most cutting-edge research is carried out, where the brightest minds from many countries work together to achieve extraordinary things. Getting into NASA requires being American, so I had ruled out the idea. But when I saw the ESA ad, I realized it matched something I was looking for: to be part of something that truly made a difference, both on a medical level (which is what I want to pursue on a space mission) and in technology. Because space technology is later applied to different sectors of society, from automation and robotization to cell phone cameras.

And while no mission arises, she works as an ESA ambassador.

— Yes, but by my own choice. ESA doesn't require it of me, nor does it compensate me, but I consider it my responsibility.

What does it refer to?

— In Spain, there are two astronauts after 30 years, and for the first time, one is a woman, which represents a series of values. And now I have a platform so people can listen and understand why it's important to invest in R&D, why we need women in STEM fields, why we need women to pursue scientific careers. How can you expect me not to take advantage of this?

The research career is very demanding and, at the end of the day, it is a reserve career.

— This is my way of contributing: to the fight against cancer, through my research; to science, through these ESA missions; to society, through outreach. It's what I've always wanted to do since I was a child: advance knowledge and dedicate myself to science to, in some way, do my part to improve society.

In conversations with elementary and middle school students, she's greeted like a superhero. She looks like an octopus star.

— How can you dream of being a physicist, programmer, or astronaut if you don't see any women pursuing it? I had no female scientific role models, beyond Marie Curie. It was during my biotechnology studies that I began to meet researchers at my university who led small research groups. And they became my role models, people close to me from whom I was able to learn what it means to be a scientist. Now, when they tell me I'm a role model for boys and girls, it makes me feel proud and encourages me to continue dedicating a lot of time to setting an example, to showing that women can be scientists and that there are female mathematicians, astrophysicists, doctors, and many other women in STEM [the acronym for science, technology, and technology]. There's so much female talent.

Why do you think fewer girls want to pursue STEM?

— Because of the labels. I'm a somewhat unusual case because I've never let anything stop me or stopped doing anything just because I'm a woman. But I do notice, now when I talk to younger people, that girls—and I hear this all too often—tell me, "I'm just bad at..." And for them to tell me that is bad, for them to label themselves. It's a self-confirmation bias that prevents you from moving forward. If you send signals to your brain that you're not good at something, that you're bad at... you killYou won't face those challenges directly, because your brain will block you and make you discard everything. Maybe a girl gives herself this label because she fails a math test. But I never tire of repeating that a mistake is never the same as failure. Mistakes are part of learning. To learn to ride a bike, you have to fall. If you throw in the towel when you fall, you've just eliminated something from your life. The same with math, or physics, or chemistry.

Doesn't it happen to them?

— They're more daring. And this has a lot to do with education, with the biases instilled in us from a young age. Women are required to be perfect in every way. We have to work ten times harder than men to get to the same level. They've created this imposter syndrome that means that if we don't feel prepared to get a 10 on an exam, we don't go. Boys, on the other hand, have a much higher tolerance for error and are more determined. We need, through social education, to eliminate biases, to stop perpetuating that women are better prepared for caregiving and men for scientific and technical careers, because that's not the case. Women, too, should be able to afford to be mediocre. It's okay! That's why I'm also excited to become a role model, because I've always tried to break stereotypes and challenge them.

At the end of 2024, you participated in astronaut training in Cologne, Germany. What did it involve?

— Both career and reserve astronauts receive the same training, although reserve astronauts receive it in two-month blocks per year to minimize impact on our jobs. It consists of basic training in certain subjects such as physics, engineering, biology, and astronomy. It also includes human factors training, such as effective problem-solving and giving and receiving. feedback, teamwork. All of this is practiced with simple simulations, but also in extreme environments.

Like when you went to the Aran Valley this winter to bivouac in the snow?

— ESA conducts cave training, where a team of astronauts must survive six days collecting samples of scientific and biological interest in a confined environment with very little privacy and poor hygiene. In my case, I participated in survival training in the Pyrenees, in the Aran Valley, where, in addition to learning how to make a fire, resolve problems like hypothermia or a broken bone, or signal a rescue helicopter, I had to survive alone in the forest for a night bivouacking, buried in the snow. I, a person with an intolerance to the cold due to a hormonal condition and who had a fear of the dark as a child, was there feeling strong and happy. It was very rewarding.

Going into space carries risks, including death. Are you prepared?

— From the moment you accept the job, you accept all the potential consequences: you accept not being able to make long-term plans for the rest of your life because you could be called away at any moment, and when that happens, you have to drop everything. It doesn't matter if you're about to get married or if your partner is giving birth. Dying is a risk, yes, but an acceptable one. I recently calculated that it was 2.7%.