Lecture Summary: Gioia Massa, NASA Astrobotanist
On Monday 27 November 2017, FSC Astronomy Club proudly presented our very first guest speaker: Gioia Massa, Research Scientist at NASA’s Kennedy Space Center, thanks to the event organizing skills of our co-Presidents Arjeet Tipirneni and Spencer Asperilla. Massa dreamed of working in space plant science in her childhood; and after years of school and dedication, she made her dream come true, holding a post-doctorate research position in her field. At KSC's Space Station Processing Facility and Life Sciences lab, Massa and her colleagues work on the Veggie program, one of the first experiments with the intended outcome of edible crops grown in the freefall of orbit. They also determine and work problems related to plants for an hypothetical deep space destination, such as Mars.
Up until Massa’s lecture, the only knowledge I had of space plant research was merely the fact that it existed in early stages. On the 2017 Space Hipsters field trip to Marshall Spaceflight Center in Huntsville, we had the privilege of being able to peek inside the Payload Operations Integration Center (POIC), a mission control satellite of sorts that directs experiments and crew activities onboard the International Space Station. While we were in the viewing room, astronaut Peggy Whitson was live on the main screen harvesting romaine lettuce, which was growing up there under a violet-colored light. Our tour guide, a PAYCOM controller (POIC version of CAPCOM), told us about the official instructions for crews not to eat certain samples so they could be returned for study; and hinted that the instructions may be overlooked from time to time while the camera is off.
So that was all I knew about it. Naturally, I was looking forward to learning more as I sat in the front row with our faculty-advisor Ron Pepino, with my notebook in hand. An audience of over 150 students was behind us, many taking notes for class since professors were awarding credit for attending the event.
The lecture started with the discussion of some science involved in growing plants in space, and differences from growing them on Earth. On the ISS, carbon dioxide levels can range anywhere from 300ppm (parts per million) to 3000ppm, while on Earth, it is mostly ±400ppm. Plants require carbon dioxide like animals require oxygen; but just like too much oxygen has an effect on animals, too much carbon dioxide has an effect on plants. Another difference is the lack of ultraviolet light in a spacecraft, due to radiation protection in the hull and windows to protect crews from direct exposure to dangerous solar radiation. Biotic issues like insects and microorganisms must be carefully avoided when preparing plants for launch, and plant fungi can still develop in orbit (which could spread to other crops or, potentially, harm the crew).
These are problems relevant to plant growth. What about problems relevant to the spacecraft and the crew? Obviously, all manufactured items in space are launched from the ground, and they weigh something on Earth. All experiments and items related must weigh as little as possible for launch and reentry. In order to be economical in Space, these items must minimize use of resources, such as power and water, in order to save as much of those already limited supplies as possible. Time is perhaps the most vital aspect. Growing and fertilizing plants takes time, and astronauts are busy people, especially on the International Space Station, which is a working full-time laboratory. For deep space missions, or self-sustaining vegetable supplies on a spacecraft, crops must be continuously scheduled and harvested due to the fact that nutritional contents of fresh vegetables degrade over time in storage.
There are solutions to these problems, whose values and costs must be identified and analyzed. One potential solution is the use of genome-editing technology like CRISPR, that may be able to alter crops’ nutritional value and other properties. Parabolic mirrors and light-pipes could solve the problem of proper lighting, since there is no effective ultraviolet transmission through a spacecraft's window. Carbon dioxide levels can be regulated and changed in plant chambers, as well as differences in humidity and temperature. In Japan, scientists are working on underground vertical farming for urban agriculture that could also provide results valuable to Space travel. Right now, though, NASA’s Veggie program is directly yielding results onboard the International Space Station.
If you have seen photographs or videos of astronauts like Scott Kelly or Peggy Whitson with space-grown lettuce and flowers, those samples were grown as part of the Veggie program. Veggie is a small container, usually in an assembly with other containers, which holds a plant in that same violet-colored light that I saw Whitson working under in the POIC. The experiment has led to successful crops such as edible romaine lettuce, one of only two plants harvested successfully in freefall so far (the other being an inedible, flowering zinnia plant). The experiment chamber contains complex items, including fans to stir air, since gasses simply float in a bubble around the plant in freefall; the aforementioned violet-colored light source; and the “pillow” which contains the plant's water supply. So far, water stress has been the most significant issue, with plants absorbing either too much or too little water. This is due to the fact that in freefall, water forms a floating bubble around the roots, causing fungal infection. However, if the water supply is reduced accordingly, the plant does not receive the amount it needs to survive. Massa is hopeful that in the future, many of these problems can be resolved with advances in technology and further data from current experiments in Space.
Massa also discussed a vital, non-scientific side to growing plants in Space: the psychological benefits. For long-duration spaceflights like that of Scott Kelly and Mikhail Kornienko, who spent a continuous year in Space together, there can be negative psychological effects. Astronauts are essentially living in the same white-walled, wired laboratory environment 24/7 - no wind, no temperature change, no grass, no rain, no other living connection to Earth except the rest of the crew. The only “outside” is the vacuum of Space. Growing plants allows astronauts to have another connection to home that is green, changing, and alive. When finished with a certain experiment, Scott Kelly continued to maintain, photograph, and love his flower collection, eventually having enough for a small bouquet on the Station’s dinner “table” (a fold-down shelf that serves only a social purpose in freefall). Kelly frequently tweeted about the flowers and his desire to keep them alive, and instragrammed photos of them with Earth in the background, one of which is linked below. This is a pleasantly out-of-character move for someone of the macho-fighter pilot archetype.
Another group of scientists who benefit from plants in a harsh environment are down at the South Pole Station. Their greenhouse (called the Food Growth Chamber) has had successful yields of tomatoes and other plants, which the station's inhabitants take great comfort in. Just like in Space, there are no living things out the window on that endless frozen plateau. Massa reports that some scientists have even been rumored to sleep in the chamber, just to be nearby the plants. Most astronauts and field scientists spend less than a year in their environment. Imagine a 3-year round trip to Mars, when the only thing out the window is the intense, velvety blackness of Space. Plants would prove to be a vital positive link to our beautiful home.
After the lecture ended, the audience asked thoughtful and relevant questions. Some even came to meet Massa after she stepped off stage. The reviews of our event were appropriately stellar, leaving all of us fulfilled. Therefore, we celebrated with dinner afterwards, attended by Massa and her husband Simone Caroti, all the Astronomy Club co-Presidents, and faculty-advisor Ron Pepino. Soon after, we found out that our event had made front page news in our student newspaper, with this photo as the cover:
There was a final question I had to ask Massa at dinner. I told her about my experience in the POIC, which she works with on a regular basis to communicate with astronauts and, therefore, her experiments. Yes, she and the Veggie team were indeed aware that the astronauts nibble on the lettuce when they aren’t supposed to. If you ask me, who can blame them? In their situation, I think we’d all sneak some home-grown veggies to go with the freeze-dried pasta.
Images: Courtesy of the Author, except where noted otherwise.
Cover image: Courtesy of USA Today
Special thanks to Gioia Massa, Arjeet Tipirneni, and Spencer Asperilla