Addressing the Plastics Problem From Space

Few other environmental topics have garnered as much widespread public interest as plastic pollution. Synthetic plastic waste, be it macro or microplastic, is now known to be pervasive throughout the Earth’s biosphere, including in land and marine environments far from human populations. The many documented negative impacts of this plastic assault on human health and our environment provide powerful motivation to urgently seek out new solutions, which could arise from the unique ability to conduct research and observe Earth from space.

The International Space Station (ISSInternational Space Station) U.S. National Laboratory held its second annual sustainability workshop during the 2019 ISS Research and Development Conference (ISSRDC(Abbreviation: ISSRDC) The only conference dedicated exclusively to showcasing how the International Space Station is advancing science and technology and enabling a robust and sustainable market in LEO. This annual conference brings together leaders from the commercial sector, U.S. government agencies, and academic communities to foster innovation and discovery onboard the space station. ISSRDC is hosted by the Center for the Advancement of Science in Space, manager of the ISS National Lab; NASA; and the American Astronautical Society.). The workshop brought together 13 invited organizations representing several economic sectors—aerospace, agricultural sciences, technology innovation, sports, retail, advanced computing, environmental, space, and government research—to discuss how the ISS can uniquely contribute to industry actions addressing plastic pollution in the environment.

At the workshop, two ideas for leveraging the ISS to address the issue of plastic pollution were proposed: 1) the development of advanced sensors for the detection and monitoring of plastic debris in the ocean, and 2) use of the unique microgravityThe condition of perceived weightlessness created when an object is in free fall, for example when an object is in orbital motion. Microgravity alters many observable phenomena within the physical and life sciences, allowing scientists to study things in ways not possible on Earth. The International Space Station provides access to a persistent microgravity environment. environment to advance the development of biodegradable polymers.

The development of advanced sensors that can accurately detect near-surface or beneath-surface waterborne plastic debris from space could significantly benefit plastic pollution prevention and cleanup efforts—not only for the open ocean but ultimately in waterways around major coastal urban cities that are known to be major entry points for ocean plastic debris.

Although no current space-based sensor has demonstrated such capability, the DLR Earth Sensing Imaging Spectrometer (DESIS, a hyperspectral sensor on the ISS) and sensors on other satellites may have the potential. Testing and field verification activities with DESIS and other sensors are currently being organized by a network group formed by the 2019 ISSRDC sustainability workshop participants. Positive results from this work could drive forward the design and development of advanced marine plastic debris sensors.

Not only is the ISS positioned to assist in the monitoring and cleanup of already existing plastic debris, it may also be used to test whether microgravity can provide new insights into pathways for the cost-effective production of biodegradable biopolymers. The production of bioplastics in space has not been systematically attempted before. However, prior investigations have demonstrated bacterial and fungal responses to reduced gravity that alter gene expression and physiological responses.

This prior work leads to a reasonable expectation that perhaps desirable metabolites (i.e., bioplastic precursors) could be synthesized in microgravity. Such research could reveal new insights that may accelerate ongoing Earth-based work to efficiently scale up biodegradable biopolymer production via biological synthesis pathways.

To learn more about the ideas presented at the 2019 ISSRDC sustainability workshop, see the report “International Space Station U.S. National Laboratory Initiatives to Address Plastic Pollution.”