From the first space station module, named Zarya, placed in orbit on November 20, 1998 to 2011’s construction completion, the facilities of the International Space Station provide powerful, safe and efficient laboratory capabilities for the more than 1,502 research investigations conducted to date on the orbiting laboratory. The space station provides a microgravity environment for researchers to conduct experiments in biology and biotechnology, human research, Earth and space science, physical science, and technology demonstrations, among a multitude of others, in what was only an engineering schematic just 15 years ago. In that time, space station educational activities on orbit have reached more than 42 million students across the globe. Further, the space station serves as a stepping-stone to deeper space exploration, demonstrating the essentials of long-term living in space.
The multidisciplinary laboratory facilities and equipment on the space station support research by NASA and its international partners, as well as National Laboratory operations managed by the Center for Advancement of Science in Space (CASIS). CASIS coordinates research by other government agencies and the private sector for the space station. These facilities were built by NASA and its international partners: the Russian Federal Space Agency (Roscosmos), European Space Agency (ESA) and Japan Aerospace Exploration Agency (JAXA).
Much of the space station research is housed in Expedite the Processing of Experiments to Space Station (EXPRESS) racks. EXPRESS racks are multipurpose racks designed to store and support investigations that only need part of a rack's space. These racks provide flexibility by housing the studies in easily replaced container drawers and lockers that can be removed and sent back to Earth with the various experiments intact. Payload racks that are long-term or permanent fixtures are considered to be space station facilities. These facilities allow easy changes of investigations and provide physical support hardware, data and video handling, among other services.
With the long-term construction of the space station, a major challenge was the amount of time necessary to enable the new capability of racks. “The majority of the space station assembly flights during early space station construction had few research payloads onboard,” said Kirt Costello, assistant International Space Station Program scientist. “Most of the payload or EXPRESS racks were not flown until the last two to three space shuttle missions,” explained Costello, which meant that the space station science facilities were not fully operational until closer to 2011.
Early investigations conducted aboard the space station were focused on human research studies of astronauts and cosmonauts constructing the station. In 2009, the number of crew members capable of living on the space station increased from three to six. This, coupled with an increase in crew member time available as assembly neared completion, allowed for more time spent on research investigations in other disciplines.
In the two years since final assembly, research and the associated facilities have taken center stage as space station priorities. New investigations are going up to the station during each expedition, which will soon maximize use of research facilities. With this increasing demand for facilities, NASA and CASIS welcome the opportunity to work with new research investigators and manage new investigation priorities.
“The collaboration between NASA and its international partners is complementary in terms of research facilities,” says Costello. “The research facilities may be operated by different space agencies, but the facilities often enhance one another to maximize research capabilities.”
Beginning with Expedition 5 in 2002, one of the most widely used facilities throughout construction of the space station has been the Microgravity Science Glovebox (MSG). It is a multipurpose facility that has been continuously used for experiments ranging from combustion science to the study of complex fluids to plant growth. Research like the Burning and Suppression of Solids (BASS), an investigation that examines the characteristics of burning fuel samples in microgravity, was safely conducted within the MSG. Plant growth experiments, such as Biological Research In Canisters-17 (BRIC-17), look at the genetic composition of the Arabidopsis thaliana plant, a small flowering plant related to cabbage, and use the MSG for harvesting purposes. The Packed Bed Reactor Experiment (PBRE) will study the hydrodynamics of two-phase gas and liquid flow through a packed column in microgravity using the MSG to contain gas and liquid. Researchers also plan to use the MSG for upcoming rodent research in space to securely contain mice aboard the space station.
The considerable amount of protein crystal growth studies performed aboard the space station during the years of its assembly continue to the current day. The Protein Crystal Growth - Single Locker Thermal Enclosure System (PCG-STES), first flown on Expedition 2 in 2001, supported a series of investigations to grow protein crystals in microgravity. JAXA’s Protein Crystallization Research Facility (PCRF) continues to support protein crystal growth investigations in microgravity, as well. The long-term study of protein crystal growth in space is beneficial on Earth. One study of protein crystals on the space station led to discovery of a water molecule in a protein-inhibitor complex that is now being used in the development of a treatment for Duchenne muscular dystrophy.
Throughout assembly, external facilities of the space station also have built up over time. Since 2007, the Sun Monitoring on the External Payload Facility of Columbus (Solar) measures the Sun’s spectral irradiance. Solar resides on ESA’s Columbus-External Payload Facility (Columbus-EPF). Researchers use JAXA’s Japanese Experiment Module External Facility (JEM-EF), installed in March 2009, for investigations into areas such as communications, space science, engineering and Earth observation. These external facilities often required highly technical Extravehicular Activity, or spacewalks, for installation.
Newer facilities like the Fluids Integrated Rack (FIR) are in use to their full capability as investigations become more complex. Six different investigation teams currently use the FIR for studies like the Advanced Colloids Experiment (ACE-M-1). These studies look at materials containing small colloidal particles to understand how to optimize stabilizers to extend product shelf life.
With so much science taking place in orbit, researchers are automating their systems to decrease the amount of crew member time necessary to run experiments. “As investigators get better at reducing crew member time for research aboard the space station, there is more time for research and more investigations may occur,” said Costello. For example, the Sally Ride EarthKam, a permanent payload aboard the space station since Expedition 1 in 2001, uses software that allows educators and students to operate and capture photos of specific locations on Earth without the help of a crew member.
ESA and the Centre National d’Etudes Spatiales (CNES), the French government space agency, run another example of an automated investigation. Their scientists have operated the Device for the study of Critical Liquids and Crystallization (DECLIC) since 2009. Though the DECLIC captures a large amount of data, it is almost completely automated, requiring minimal crew member time. The DECLIC is a multi-user facility designed to study transparent media and their phase transitions in microgravity.
“In very few places on Earth do you have a biology lab, sitting right next to a combustion furnace, sitting right next to an Earth observation window,” said Costello about the unique multidisciplinary environment for research aboard the space station. “We’ve got so many different types of science aboard the International Space Station that it really is a unique opportunity to be able to combine those and think of not only research in one particular field, but also multidisciplinary research.”
Using the distinctive microgravity environment of the space station enables researchers to use experiments to generate new hypotheses that can be studied in a short period of time, similar to research conducted in an Earth-based laboratory. The facilities developed, installed and operationalized for the space station during the past 15 years have contributed to new discoveries in the various science disciplines studied in orbit. With the continued focus on research in the space station’s years ahead, these facilities will continue to contribute significantly to the body of scientific knowledge to ultimately benefit the people of Earth below.