Ask International Space Station facility engineers and payload operations teams at Marshall Space Flight Center what makes them proudest, looking back on two decades of developing, testing and supporting science in orbit. Many will glance upward, as if the source of that pride might be passing overhead at that moment, 250 miles up.
Just as often though, they look to one another.
“We all share one goal: to get experiments developed, tested, manifested and flown to space, successfully conducted in orbit, and returned to Earth for analysis and practical application,” Shawn Reagan, materials science research portfolio manager in Marshall’s International Space Station Projects Office, said. “And it’s all in service of furthering our scientific knowledge, advancing our journey of exploration into the solar system, and aiding development of a thriving commercial space economy.”
Currently celebrating more than 20 years of continuous crew operations, the station is a marvel of teamwork. It’s home to round-the-clock science, with some 200 experiments underway at any given moment, overseen by astronauts and science teams on the ground. Crew and station operations are led by NASA’s Johnson Space Center, while Marshall oversees all payloads from its Payload Operations Center, monitoring use of the 15 unique science hardware facilities developed, built and managed there for the agency.
Central among them are the “EXpedite the PRocessing of Experiments to the Space Station” multipurpose payload shelving units, or EXPRESS Racks. Developed and tested at Marshall by NASA and Boeing, the first two racks were delivered to the space station on STS-100 in 2001 and have been in continuous operation ever since. Today, there are 11 of them – including three streamlined Basic EXPRESS Racks – the last delivered in 2020.
Up to 80 experiments may be in process in the racks at a time, controlled by station crew or remotely by NASA personnel in Marshall’s Payload Operations Integration Center. There, a cadre of nearly two dozen team members monitor the racks around the clock, every day of the year, communicating in real time with the crew and researchers on the ground.
“The sheer volume of science that’s been conducted using the racks is overwhelming,” Shaun Glasgow, former EXPRESS Racks project manager at Marshall, now project manager for the Material Science Research Rack, said. NASA estimates the racks have yielded more than 99 years of combined operational hours since the first were installed in 2001 – contributing to about 900,000 combined hours of research.
“As we prepare to return human explorers to the Moon and journey on to Mars, it’s even more exciting to consider all the scientific investigations still to come,” he added.
Marshall also manages the station’s self-contained Microgravity Science Glovebox and Life Sciences Glovebox, installed in 2002 and 2018, respectively.
Built by German developer Astrium for the European Space Agency and flight-tested at Marshall, the Microgravity Science Glovebox remains a permanent, high-demand fixture on station. Crew members use built-in glove ports in the sealed facility to safely manipulate liquids, particulates, and even open flame – conducting investigations in the areas of fluid physics, combustion science, biotechnology, materials science and more. The facility has enabled more than 60,000 hours of powered science research to date.
Demand on the glovebox was so great that the space station partners commissioned a second dedicated facility, the Life Sciences Glovebox. The new facility, roughly the size of a large fish tank, primarily aids research into microgravity’s long-term impact on the human body. It was built by the Japan Aerospace Exploration Agency and the Dutch firm Bradford Engineering. Marshall contributed the secondary support structure, power system and thermal control system. As with the racks, glovebox experiments are supported 24 hours a day by dedicated personnel in Marshall’s Payload Operations Integration Center.
Dramatically extending the station’s research capabilities are two unique lab facilities, the Materials Science Research Rack and the Window Observational Research Facility, better known as WORF. Jointly developed by NASA and ESA and launched in 2009, the Materials Science Research Rack houses the European Materials Science Laboratory. Capable of reaching temperatures up to 2,500 degrees Fahrenheit, it enables studies of metals, alloys, semiconductors, ceramics, glasses and advanced metallurgical processes. Designed and built by Boeing at Marshall, WORF offers Earth science and space science researchers the means to observe environmental changes on Earth, track hurricanes and other natural disasters, and document meteor showers and other near-Earth phenomena.
David Brady, associate program scientist in NASA’s ISS Program Research Office at Johnson, says there have been three distinct chapters in the life of the space station.
“Its first decade was devoted to assembly in orbit, and its second was all about research and technology development, continuing to grow and refine its utility as a landmark science platform,” Brady said. “Now we’re in the station’s third decade, the era of full scientific utilization, expanded commercial value, and global partnership.”
Lynn Farris, ISS Payload Facilities team lead, said Marshall’s payload facility project managers welcome the challenge. “During initial station construction, we were lucky to log eight hours of science each week. Now the 15 station payload facilities managed by Marshall can clock in excess of 100 hours per week,” she said.
Farris heads the team that helps scientists plan and verify new glovebox and rack experiments, conducting preflight tests using the Payload Rack Checkout Unit housed in Marshall’s Space Station Integrated Test Facility. Marshall also maintains a specialized checkout facility, complete with furnace, for developing and certifying Materials Science Research Rack payloads. Additional Payload Rack Checkout Units reside at Johnson and at NASA’s Kennedy Space Center and Glenn Research Center.
Marshall facilities and payload operations teams also work closely with the station crews on the other end of the process. “The crew’s feedback improves our processes, and helps us gauge how well the hardware is working and where it needs refinement,” Farris said.
Science teams and hardware developers at Marshall are already looking ahead to new challenges, drawing from their successes on the space station to develop next-generation experiment racks and lab facilities that could serve in NASA’s proposed Gateway lunar orbiting outpost and on future research bases on the Moon and, in time, Mars.
The space station has been home to 242 individuals from 19 countries, working with more than 4,000 scientists in 108 countries to conduct some 3,000 total research investigations. Learn more about station research and technology here.
Editor’s note: Rick Smith, a Manufacturing Technical Solutions employee, supports Marshall’s Office of Strategic Analysis & Communications.