Dr. Silke Asche (She/Her)

Chemist in Astrobiology
Astrochemistry Laboratory (691)

How did you end up working at NASA Goddard?

I never actually planned to become an astrobiologist, or even a scientist. When I first started studying chemistry, I ended up quitting after two years. However, I still loved the subject, so I trained as a chemical technical assistant at a German apprenticeship school. Because it was a school program, I qualified for Erasmus (a European Union student exchange) and was assigned (rather randomly) to a research group in Scotland. Although I had hoped to end up in London, being thrown into academic research in Glasgow turned out to be very lucky, and it helped me discover my passion for research. I began as an inorganic chemist, working on nanoscale metal-oxygen clusters called polyoxometalates, which are very small brown crystals, and I enjoyed it so much that I stayed on as a visiting student for two years.

From there, I earned a master's degree by research, followed by a PhD in chemistry. During my master's, I joined the Origin of Life (OoL) team, which shifted my focus from inorganic chemistry to organic prebiotic chemistry. One of the biggest challenges in the OoL field is that we do not actually have a definitive definition of life, which makes it difficult to detect when something becomes “alive.” I realized that detecting the transition from a chemical system to a living one is a challenge shared by OoL research and the search for life beyond Earth. Wanting to learn how researchers approach this question from a planetary science perspective and to develop tools that might work both in the lab and on other planets, I applied to join the Agnostic Biosignature Collective at NASA Goddard.

What was your first big research achievement?

During my master's and PhD, I became increasingly interested in laboratory automation. What began as a side project led me to develop an automated platform for running long-term experiments. At first, I had no background in coding or engineering, and I did not consider myself especially handy. Learning to design parts in Onshape, 3D-print them, and assemble everything was a long but very rewarding process.

In the end, I built a fully functional automated system: “The Chemical Selection Engine”. This system was the first of its kind used in Origin of Life research, which opened up new possibilities for studying small-molecule prebiotic reactions in long term reactions, chemistry that might have started the emergence of life as we know it. This was research that would have been nearly impossible without automation.

Tell us about the research projects you are currently working on.

My main project is to develop new ways to detect signs of life (known as biosignatures) as we don't know it, using an instrument called a mass spectrometer. A mass spectrometer measures the weight of molecules, which makes it possible to identify them. These instruments are used here in laboratories on Earth, but they are also already deployed on Mars, for example, on the Curiosity rover, and will fly on future missions like the Rosalind Franklin rover (Mars), Dragonfly (Titan), and Europa Clipper.

Because a mass spectrometer picks up a lot of different signals, the data can easily become “noisy.” That's why a big part of my work involves running tests on known reference samples and environmental samples to find the best ways to process and interpret collected data. This is crucial for avoiding mistakes, like “false positives,” where we might think we have discovered something exciting when we have not.

I am also involved in a separate project that explores how meteorite impacts change the chemical makeup of an environment. It is a bit different from my usual focus, and I am very excited about it as it involves my very first field trip, which is a big change from my usual windowless laboratory! I cannot wait to collect my own samples and then analyze them on the mass spectrometer back at the lab.

What is one of your favorite moments in your career so far?

One of my favorite moments in my career so far came from what initially seemed like a disappointment. I was organizing an early-career conference when COVID hit and forced us to move the meeting online. It felt disheartening at first, but it actually sparked an incredible effort that led, after countless evenings on video calls with the other 3 co-founders, to the start of the Origin of Life Early Career Network (OoLEN). Since then, OoLEN has grown into a global research community of more than 250 early-career scientists, supported the publication of three papers, and hosted four in-person meetings. It has been amazing to see early-career researchers come together, share their perspectives, and have a real impact on the OoL field. This network is such an inspiring community, and I am incredibly grateful and proud of what we build together. Eventually, I got to organize an in-person OoLEN meeting in Canada in 2022. Finally seeing everyone “in 3D” after so many Zoom meetings, was surreal but incredibly rewarding.

What is one thing you wish everyone knew about your particular field of science?

I wish we were better at communicating how little we know about life on Earth and in the universe. Every assumption we make is based on the one example we have, life on Earth (whose origin we do not even fully understand). That is why we get so excited when we find water or detect amino acids elsewhere; it fits our Earth-centric idea of what life is. But if I tried to draw conclusions from just one data point in any other research project, I would call that pretty poor practice. Of course, we can only use the information we have, but it is a stark reminder of how much more we still have to learn. I would actually be a bit disappointed if we ever found life elsewhere and it turned out to be just like ours, that would be so boring!

Who inspires you?

One of my favorite real-life stories is Shackleton's Endurance expedition. Back in 1914, they set out to cross Antarctica—well, they tried. The ship got trapped in the ice and eventually sank, but the truly remarkable part is that everyone survived. While I was living in Scotland, I got to visit the town Dundee and see the Discovery, another Antarctic exploration ship from that era, which even had a (fairly basic) laboratory on board. That glimpse into early scientific exploration really stuck with me. While expeditions today look very different and thankfully science is much more inclusive and diverse now (even if there is still lots of work to be done), I love the idea of tackling questions with that same spirit of curiosity and boldness. We do not know the answers to the problems we study, and that means we have the chance (and privilege) to discover something completely new, and hopefully enjoy the journey along the way.

What is a fun fact about you?

When I first moved away from my childhood home, a village of just 2,000 people, I wanted to become a "big city person". Over time, I realized that every place you live changes you in some way. After living in four different countries, I've found that it's not just the places themselves but also the cultures and communities that shape who you become. I like to think I carry a little piece of each country with me now, which mostly shows up in my accent and my very random food cravings. The only downside is that giving a quick answer to “Where do you come from?” has become nearly impossible without telling my whole life story—but hey, it's a great conversation starter!