2017 ASHS Annual Conference

Microgravity can affect the growth of plants, which has implications for future space food production. The objective of the NanoRacks-Girl Scouts of Hawaii-Arugula Plant Growth Project was to determine the differences between arugula seedlings grown in microgravity on the ISS and those grown on Earth. The ISS Team consisted of eight high school students. Assisting were mentors in horticulture, engineering, electronics, and computer programming. A horticulture group was added to the team’s engineering, design, programming, and communications groups. The team selected arugula (Eruca sativa Miller), and the treatments were organic nutrients, synthetic nutrients, and no additional nutrients. The investigation included two MicroLabs, two controllers, and two unique interface boards that controlled one experiment. Photo capture, photo lighting, grow lighting, and watering were shared between the two controllers and three plant growth tubes. All seedlings had the same light (red and blue LEDs), water, growth medium, and temperature conditions. The team designed the incubator to hold the hydroponic system. This included grow tubes, LED lights, arugula seeds, purified water, PVC water line tubing, PVC water bag, micro valve for controlling water flow, assorted integrated circuit chips, resistors, capacitors, and connectors. The team designed programming to enable the payload to operate remotely while on the ISS. Programming and electronic interface circuitry managed the water bag, timing of the water cycle, grow lights, and photo frequency. The experiment was designed to function for the duration of the flight onboard the ISS. Flight simulations were successful and provided high confidence the experiment would be a success while on the ISS. Upon examination of the returned experiment, no seed germination had occurred. While the experiment mechanically functioned as expected, there were no traces of water in the capsule compartment. The team’s hypothesis was the water storage bladder leaked and evaporated while in pre-flight wait status. The team assembled the experiment in late January 2015 with a target launch in February. Due to SpaceX booster rocket failures and the prioritization of other flight missions over the ISS experiments, the actual launch date was 14 July 2015. The ISS Team learned to devise experiments and develop new, life-changing skills in scientific research, coding, data analysis, decision-making, project management, and collaboration. I thank Colleen LaClair, James LaClair, Gail Hannemann, Girl Scouts of Hawaii, NanoRacks LLC, NASA, National Laboratory Education, and Valley Christian High School for their assistance.