On March 8, 2017, astronauts aboard the International Space Station (ISS) conducted a significant harvest of plants cultivated in microgravity. This event marked a pivotal moment in NASA's ongoing research into space agriculture, aiming to support long-duration missions by developing sustainable food sources beyond Earth.

Background on Space-Based Plant Cultivation

Growing plants in space presents unique challenges due to the microgravity environment, which affects water distribution, nutrient uptake, and overall plant growth. Understanding how plants respond to these conditions is crucial for future deep-space exploration missions, where resupplying from Earth would be impractical. NASA's Veggie project, initiated in 2014, was the first to successfully grow edible plants aboard the ISS. This system utilized a growth chamber equipped with red, blue, and green LED lights, along with a porous clay substrate, to cultivate crops like lettuce and radishes. The success of Veggie laid the groundwork for more advanced plant growth systems.

The Advanced Plant Habitat (APH)

In 2017, NASA introduced the Advanced Plant Habitat (APH), the largest fully automated plant growth research facility on the ISS. Developed in collaboration with ORBITEC, the APH is a closed-loop system designed to conduct both fundamental and applied plant research during experiments extending up to 135 days. It features an environmentally controlled growth chamber with over 180 sensors to monitor and regulate conditions such as temperature, humidity, and light. The APH aims to provide insights into plant growth mechanisms in space, supporting the development of sustainable food sources for future missions. ([nasa.gov](

Harvesting Plants for Return to Earth

On March 8, 2017, astronauts aboard the ISS harvested plants grown in the Veggie facility. These plants were cultivated on petri plates as part of the APEX-04 study, which focused on understanding the molecular changes that occur in plants when grown in space. Astronaut Peggy Whitson played a key role in this harvest, assisting researchers in studying these changes. ([nasa.gov]( The harvested samples were prepared for return to Earth aboard the SpaceX Dragon spacecraft, scheduled to splash down in the Pacific Ocean on March 19, 2017. Upon arrival, NASA personnel analyzed the samples to gain insights into how space conditions affect plant biology. This research is vital for developing strategies to grow food in space, ensuring a sustainable food supply for astronauts on long-duration missions.

Student Experiments Aboard the ISS

In addition to plant cultivation, the ISS serves as a platform for various student experiments. On the same day as the plant harvest, a variety of student experiments submitted from schools across the United States were activated inside the orbital laboratory. These experiments aimed to explore ways to reduce infections, improve muscle injury treatments, grow plants on Mars, filter bacteria, and solve common slippery surface problems. ([nasa.gov](

Implications for Future Space Exploration

The successful cultivation and harvesting of plants aboard the ISS represent a significant advancement in space agriculture. Understanding how plants grow in microgravity is essential for developing sustainable food sources for astronauts on long-duration missions to the Moon, Mars, and beyond. The research conducted on the ISS provides valuable data on plant growth mechanisms, nutrient requirements, and potential challenges in space-based agriculture. As NASA continues to plan for deep-space exploration, the ability to grow food in space will be crucial for mission success. The lessons learned from these experiments will inform the development of closed-loop life support systems and autonomous greenhouses capable of supporting human life on other planets.

Conclusion

The March 8, 2017, plant harvest aboard the ISS was a milestone in NASA's efforts to understand and develop space-based agriculture. By studying how plants respond to the unique conditions of space, scientists are laying the groundwork for sustainable food production systems that will support future human exploration of the solar system.

Sources

NASA — Harvest Day on Station as Kids Space Research Begins — NASA — New Plant Habitat Will Increase Harvest on International Space Station — NASA — Advanced Plant Habitat — NASA — Astronauts Harvest Radish Crop on International Space Station — NASA — NASA Astronaut Paints a Picture of Success Growing Plants in Space —