Dr. Keiko Nakamura-Messenger: Exploring the Cosmos at Atomic Scales
Dr. Keiko Nakamura-Messenger is a cosmochemist and materials scientist in the Astromaterials Research and Exploration Science Directorate at NASA’s Johnson Space Center. She has a Ph. D. in Material Science from Kobe University in Japan. Keiko is currently the lead of sample site science and the deputy curation lead of the OSIRIS-REx mission, as well as a science team member of the Japanese Hayabusa2 mission. She is an expert in the analysis of extraterrestrial materials, especially in analysis of samples at the nano-scale, e.g. Stardust samples and interplanetary dust particles. Her research led to the discovery of two new minerals, Brownleeite and Wassonite. Asteroid 7862 Keikonakamura is named in her honor for her pioneering work on microscopic organic globules in meteorites, furthering understanding of organic material in the solar system.
Kat Gardner-Vandy, an Earth and space science consultant and research associate at the University of Tulsa, interviewed Keiko for the 51+ Women in Planetary Science series over email.
Tell us the story of how you came to love science, particularly space science.
My parents bought an encyclopedia for my older siblings. There were 20 books and each had a theme such as Human Anatomy, Entomology, Botany, Geology, Astronomy, and Mineralogy/Petrology/Fossils with lots of pretty pictures in them. I finished reading all of them before going to kindergarten. The subject that fascinated me the most among the whole series was “Comets”, especially the high-contrast telescope images of various comets that were beautiful and scary at the same time for my young mind. I read them over and over again and asked a lot of questions about comets, but none of my family members could answer them. Decades later, here I am as a scientist analyzing cometary dust particles in a laboratory. I have been feeling so lucky every time I get a chance to hold and work on a new piece of a comet with my own hands.
Where did you go to school for undergrad, and what prompted you to go into material science for your PhD?
I went to Kobe University in Kobe, Japan for undergrad. It was there that I met one of my most influential mentors, Professor Kazu Tomeoka, an expert of primitive astromaterial sample research. He is one of the pioneering researchers who analyzed interplanetary dust particles (IDPs) collected in the stratosphere in early 1980s. In one of his lectures, he said, “In the near future, we can collect samples from asteroids and comets by ourselves. There is need to wait for the meteorites to come and fall from the sky. Isn’t that exciting? You can study those fresh samples from space if you like.” Who could say no to this?
However all of those samples (IDPs, comet Wild 2 samples returned by STARDUST, and asteroid Itokawa samples returned by Hayabusa) are smaller than the thickness of a human hair, invisible for human eyes (average 10 micron diameters). And yet they are so precious, each containing secrets of the origin and ancient history of the Solar System. So I had to be very good at small sample handling (micro-manipulation) and also using cutting edge nanotechnology. Material science covers micro-crystallography, mineralogy, basic inorganic and organic chemistry using various microanalysis instruments. The two new minerals I discovered (brownleeite is from a comet, and wassonite was found in a meteorite) were the smallest minerals ever approved by the international mineralogical association. They were both 100 nm in size. I think my material science background helped a lot on this.
How did you transition into the position at JSC?
A year and a half before finishing my PhD thesis in 2001, I stayed at NASA/JSC in Houston, Texas, as a co-op for three months and worked on a Tagish Lake meteorite project with Dr. Mike Zolensky (NASA/JSC) with a grant I received from the Japan Society for the Promotion of Science for science graduate students. At that time, I was working together with Professor Sho Sasaki (University of Tokyo), analyzing samples that simulated space weathering effects on micro samples. During my co-op stay, I met Dr. Lindsay Keller (NASA/JSC) who is an expert in micro-analysis of space weathering effects on Apollo lunar regolith samples as well as IDP studies. Lindsay was looking for his first postdoc candidate, and I applied for the position. As soon as I received PhD in September 2002, I came to JSC to be his postdoc.
You are involved in several missions. How did you get involved, and what is your role?
For the European Space Agency’s Rosetta mission, I am involved with the onboard instrument MIDAS (micro-imaging dust analysis system). I was an undergraduate summer intern with the Lunar and Planetary Institute, and I was looking for graduate schools in planetary science which could give a research assistant job. My intern supervisor, Dr. Zolensky, advised me that there was a graduate student job opportunity involving a cometary dust analysis instrument on the Rosetta spacecraft. I went to Germany for graduate school and worked under another dust-research guru, Dr. Wolfgang Klöck. My main memory from my time there was calibrating the instruments probably thousands of times rather than analyzing samples. It’s been almost 18 years since then and the Rosetta spacecraft has finally arrived at the target comet (Comet 67P/Churyumov-Gerasimenko) last summer. It has been a very exciting year to learn all the new insights of the comet sent back by Rosetta’s onboard instruments and the lander.
I had worked as a sample processor for the curation laboratory for NASA’s STARUDST mission. The curation cleanroom facility for STARDUST mission samples was under construction in the same building where I was doing a postdoc here at NASA/JSC. It was 2-3 years before the cometary samples actually came back to Earth and they were looking for someone who could handle small samples. I had been studying IDPs, so I had very stable hands to manipulate sub-micron particles, but I had never worked with aerogel, STARDUST’s collector medium, which is extremely light and fragile. I trained and practiced how to extract cometary particles from aerogel using simulated samples, and I learned how to operate specially built instruments for about 10 months before the sample return. Working at the STARDUST curation lab was the best experience of my life. I was the first person to handle most of the cometary samples, and I created thousands of sub-sections of the Comet Wild-2 samples and communicated with over hundreds of researchers all over the world.
Between research, curation activities, mission work and having a family, you are busy lady! How do you keep up with everything?
I have been keeping minute-by-minute diaries at work. I wish I had done that for my private life, too. I used to love getting up early and going to my Crossfit gym to keep my mind sane. Right now I’m pregnant so can’t really do a 100-lb back squat or rope climbing, so I enjoy sleeping an extra hour cuddling with my 2-year-old. My husband is an astrophysicist working at the same research facility. We collaborate at work, eat and commute together, so basically we see each other 24/7. He helps me a tremendous amount on family matters and research.
What does your future hold? What would you like to be doing in 10 years?
I actually know exactly what I will be doing 10 years from now. NASA’s OSIRIS-REx mission will return samples from Bennu, a water- and organic-rich asteroid, in 2023. As the deputy sample curator of the mission, I will be very busy working on these samples. By that time, the Japanese mission Hayabusa 2 will have returned samples from another water- and organic-rich asteroid Ryugu, and I am the NASA sample curator of the Hayabusa2 mission. We will be analyzing the sample as well. I can’t wait to see what kind of untold mysteries Bennu and Ryugu will bring us. I’m also hoping that the price of commercial space travel will become affordable in 10 years so that my husband and I can have a couple of minutes of outer space experience.
What do you like to do in your “free” time?
When I am free, I let my mind wander and think about the effects of Betelgeuse explosion, or what it’s like to be in a blackhole or intergalactic wars. What I really like to do in my free time is to create some story books for my children based on my imaginations, but at this pace it’s going to be completed when my kids graduate.
Any additional comments for young scientists?
Stay focused working on the subjects you are really passionate about. That gets you through any hardships.
Any additional comments on being a mom or the two-body problem?
Only thing I had sacrificed to solve the two-body problem was giving up on my Japanese citizenship since Japan is one of the rare countries that don’t allow dual citizenship. But by doing that, I could not only stay with the family but I also could work as US federal agency’s scientist. I myself don’t consider this to be a big sacrifice because my colleagues back in Japan are having an even harder time. Compared to them, I am extremely lucky. Lucky to be a scientist to be paid for what I enjoy doing and a pure miracle to be a mom.
Thanks to Keiko for sharing these insights and advice, and thanks to Kat for conducting this interview!