We asked microbiologist and NASA astronaut Kate Rubins about her time on the International Space Station, the challenges of working with bugs in space, and what's next for science that is out of this world.
QWhat inspired you to make the giant leap from academia to NASA?
I wouldn’t say it was exactly a plan. I was in academia and I was a fellow at the Whitehead Institute running a lab there. I wanted to be an astronaut from the time I was a child, but I simply didn’t think it was a real career path. One of my friends was looking at the federal jobs website for the government and found a posting for astronaut applications. She mentioned it mostly because she thought it was funny, but she encouraged me to apply.
QHow long did the whole process take through recruitment, training, the expedition itself and any duties you had to do when you returned?
The recruitment process is about a year; it's a series of interviews at NASA and a whole bunch of documentation. I think we had over 18,000 applicants for the most recent class. You’re then selected as an astronaut candidate, which involves a three-year training process to learn all the things needed to carry out a successful space mission. It's a pretty varied training programme and very intense as well. We do a lot of survival training, both in water and on land; we learn how to fly a T-38, which is a supersonic fighter jet trainer; we learn about the tasks we are going to be conducting on board; and how to do a spacewalk. It takes hundreds of hours of training in our pool. After finishing the astronaut candidate training route, you graduate to astronaut and wait for your mission assignment. Once mission-assigned, it's about two to two-and-a-half years of mission-specific training, a great deal of which is with our international partnerships in Russia, Japan, Canada, Europe, and on the partner modules, as well as the Soyuz vehicle.
QWhat other duties do you have as an astronaut?
I’m currently doing a rotation as the Deputy Director of the Human Health and Performance Programme. It's one of our large directories at the Johnson Space Centre. We oversee all of the laboratory activity, so all of the spacecraft environmental monitoring and flight surgeons: anything related to medical wellbeing, human health and performance. We help to plan spacewalks for those currently on board and act as capsule communicator (or capcom) in mission control. If you remember any Apollo-type activities, there was always the capcom astronaut in the spacecraft and we continue that. We also provide support for future spacecraft design, as well as current operations on the International Space Station (ISS).
QHow did working on Ebola and Lassa fever in high-level biosafety facilities and during field work prepare you for NASA?
It's actually an excellent parallel. You’re in a difficult environment, you’re pushing yourself pretty hard, and you have to figure out what is the operational template you can sustain without pushing too hard. In space you always have to be ready for a spacecraft emergency and be able to respond. Setting up a lab in the middle of the Congo was incredibly challenging. We had very limited power for the equipment as it was generated by solar arrays, and we had challenges with computing, data transfer and infrastructure. So there are almost identical challenges in the remote environment and the ISS. I spent a lot of my life putting on a biosafety level four suit and calling it a spacesuit. Now I’m putting on a spacesuit for real.
QYou did a lot of experiments on the ISS. Did you answer any microbiological questions?
Yes, absolutely. There's an ongoing experiment to look at different microbial surfaces and microbial growth, and we also did a lot with the biomolecule sequencer. We are working on a project now that goes from swab to sequencer on board. I organized an all-day workshop recently where we were talking about what questions researchers and NASA want to answer about the microbial environment on board the ISS; how do we want to understand future spacecraft? It's a very interesting environmental niche that is completely separated from Earth, and we have been there continuously for 16 years. The basic researcher in me is very interested in the microbiome of the ISS and how that might be changing, whether it is affected by radiation and the impact of periodically introducing new humans into this environment.
QWhat impact do you think genomic analyses will have on life and research aboard the spacecraft?
That was really a proof of principle experiment. We were trying to determine if we could even perform DNA sequencing in space, as you don’t necessarily know if the equipment is going to work as planned. Fluids behave completely differently in microgravity. We used a nanopore sequencer and wanted to understand how fluids flow across the membrane, and if the technology could survive the extreme conditions of lift off. It was very successful and opens a door for us to use the technology, not just for microbial monitoring, but for any kind of real-time detection. For example, if we’re interested in bone or muscle loss or another physiological process. We are currently waiting for a return vehicle to Earth so that we can carry out the analysis in an Earth lab.
QWhat are the biggest challenges when performing experiments in space?
When you’re in the lab, you walk up to your lab bench, sit on a lab chair, and you are planted there by gravity. Aboard the space station you’re floating and very unstable. So one of the first things I had to set up was a lab bench with little stirrups for my feet, so that I could put my feet in and stabilize myself. When doing lab work you use your feet to control how you’re positioned. You also have to react to any forces, so even the force of putting a pipette tip onto a pipette, or ejecting the pipette tip, could send you in the opposite direction. Watching and controlling the behaviour of fluids is also very interesting. The scale that we use for molecular biology is a few μl to a few ml or less and actually behaves quite well in space. The surface tension of any of the tubes or the pipette tips that we’re using will keep that fluid well contained. But if you have a 50 ml conical with fluid in it you have to be careful not to jostle that because the fluid is going to fly out of the conical.
QHow are the living conditions on the ISS?
My sleep station was right next to my lab bench. You’re living inside your lab and also living inside your support system. The spacecraft generates all of the water and air using a closed loop system; water is recycled, CO2 is scrubbed and oxygen is generated from water. You’re living in the middle of a machine surrounded by pumps and solar arrays, so there are some unique challenges. If you can imagine that the lab surface is in an elevator and there is a freefall going from the ninetieth floor, everything rises up from that lab bench. That's what it's like when you are in freefall, in microgravity. It doesn’t take that long to learn how to cope with all of these things and it becomes second nature. I think that if I was going to work in a lab on Earth, I’d probably go around sticking Velcro on everything! There's also a lot of pressure. You are living just centimetres away from absolute vacuum. We’re really reminded of that when we go out on spacewalks. It's not an incredibly safe place to work but I think it's worth the cost for the potential of discovery. It is the most exciting and terrifying place I’ve ever seen, to go outside of our atmosphere and off our planet.
QWhat's the most important thing that you’ve learnt from being in space?
One of the most important things was just how amazing the vehicle is, the ISS. It's huge, the size of a football field, and completely assembled in space by humans. It's an engineering and scientific marvel, together with the strength of the international partnership that was required and is still ongoing. I lived up there with a Russian cosmonaut and a Japanese astronaut, and we take it for granted as space flyers that we’re working together. There is a lot of work with our partner space agencies on the ground; these are extremely strong relationships and it's a really long history of collaboration. The sheer effort that has gone into building this vehicle is pretty amazing to me.
QWhat are you going to be focusing on next?
I’m still an active astronaut. I am very interested in what we’re doing scientifically on the ISS. We are doing hundreds of experiments for expeditions and I’ve been thinking a lot about how we can do more high-throughput biology. The space station is going to be around for a while but there is a limited lifetime, so we need to think about what questions we need to answer with this incredibly capable lab. We may not always have a laboratory this capable in space, so what are the really critical things that we want to answer in this unique window of time? A huge goal of NASA is to understand what is affected in human physiology, not just to understand astronaut health for exploration, but also to give us some fundamental insight into the possibilities of fluid shifts or immediate unloading of the bones. We can understand some basic cellular and human physiology because we’re putting people in this unique environment, so that answers some basic research questions that aren’t just dedicated to space life.
QWhat advice would you give to any researchers out there who could also be budding astronauts?
Whatever it is that you’re interested in, you can be an astronaut, involved in the space programme and thinking about exploration missions. Bringing strong scientific ideas to what we’re doing in space is incredibly important and microgravity could affect different elements of people's research. Whatever country they are in, I really encourage people to go through the space agencies in their country and look into continuing that research or thinking about how their research might have applications for future exploration. For anybody that wants to be an astronaut, be incredibly passionate about what you do. I never wanted to stop being a virologist. I don’t really think I stopped; I just changed careers a little bit. To me, the most exciting thing I could think of to do with my life was to get a chance to have a scientific question and do experiments in the lab. To answer that question, generate 20 more questions, and then try to answer those. I think that curiosity pairs very well with our desire to explore the solar system.
Kate Rubin's NASA profile can be found at https://www.nasa.gov/astronauts/biographies/kathleen-rubins and photos of her time in space at https://www.flickr.com/photos/nasa2explore/sets/72157664950488325.
Interview by Emily White