The ISS⎯the largest orbiting man-made object⎯is being constructed to support three activities: scientific research, technology development, and development of industrial applications. Its facilities allow for ongoing research in microgravity, studies of other aspects of the space environment, tests of new technology, and long-term space operations. Its facilities enable astronauts to conduct many different types of research, including experiments in biotechnology, combustion science, fluid physics, and materials science, on behalf of ground-based researchers. The ISS also has capability to support research on materials and other technologies to see how they react in the space environment. In general, conducting research in a microgravity environment allows scientists to eliminate the influence of Earth’s gravity and can result in discoveries of properties and reactions that would be masked on Earth. Some researchers believe that conducting scientific experiments in microgravity can yield potentially groundbreaking results in areas as diverse as stem- cell culturing, vaccine research, plant and seed research, and targeting drug-resistant microbes. Testing materials and technologies in space allows researchers to determine the impact of the harsh space environment on these items for potential future use in space vehicles or satellites. There are five main partners involved in supporting the development and manning of the ISS: the United States, Russia, Japan, ESA (which includes a number of participating countries), and Canada. The ISS consists of two separately administered (though conjoined) parts: (1) the U.S. operating segment (USOS), with contributions from its international partners (ESA, JAXA, and the Canadian Space Agency (CSA)), and (2) the Russian segment. Russian research is separate from the USOS operations: Russia has no utilization rights to U.S., European, or Japanese modules and NASA has no utilization rights to Russian modules, though NASA told us there are mechanisms for scientific collaboration and hardware sharing among all agencies. According to NASA, it provides a portion of ISS resources (including crew time, facilities, and launch capabilities) to the partners based on international agreements with each partner in exchange for its contributions to the ISS. Each partner facility has research accommodations that can be used and shared among the partners as stipulated in the agreements. Scientific research facilities currently available inside the ISS are generally mounted in modular, refrigerator-sized mounts called racks or ExPRESS racks, which provide the utilities necessary for conducting research, including electricity. Each rack contains lockers, drawers, or other inserts that can be used to install research payloads and are changed as necessary. The racks may also contain semipermanent equipment, such as freezers, incubators, or glove boxes. Research payloads are sent to the ISS in a flight-certified piece of hardware that may be small in size. This hardware is generally then installed in one of these racks, and the experiment is operated until the research is completed. Once completed, the payload may be returned to Earth for analysis or research data are transmitted back to Earth for analysis. Research can also be conducted on the exterior of the station in unpressurized facilities; for example, the Materials International Space Station Experiment is conducted in such facilities. Facilities on board the ISS and NASA’s plans for its own utilization of the ISS have changed over time. When NASA adopted The Vision for Space Exploration (Vision) in 2004, it set forth a plan to explore space and extend a human presence across our solar system with dual goals of returning humans to the moon by 2020 and later sending humans to Mars and other destinations. It also dictated that NASA focus its research efforts on board the ISS on its Human Research Program supporting future human space exploration, including studying the effects of the space environment on humans; on technology development and test for exploration; and on developing operational protocols for successful long- duration space operations. Though ISS had originally been intended to be a broad-based research facility, the Vision required NASA to focus its ISS research on supporting space exploration goals with an emphasis on understanding the impacts of the space environment on astronauts and developing countermeasures to these effects. As a result, NASA reduced the scope of its ISS research; the agency conducted a zero-based review in the fall of 2005 and determined that some fundamental life and physical sciences tasks were not “highly relevant” to achieving the goals of the Vision. The agency canceled some existing grants in this area and stopped soliciting any new research, which caused affected ISS scientific research communities to shrink or turn to other research areas. NASA also reassigned its personnel involved with the fundamental sciences, including space biology (such as animal, plant, and microbial research), and reduced its portfolio of research on fluid physics, combustion, materials science, biotechnology, and fundamental physics. Table 1 depicts some changes in ESMD flight research conducted in 2002 and 2008 that illustrate the redirection of focus. Hardware needed for research projects was also canceled or delayed by NASA or commercial developers, either because of the change in research priorities or other constraints, such as the pause in shuttle flights after the loss of the Space Shuttle Columbia. This included animal research facilities, the Life Sciences Glovebox, the Centrifuge Accommodation Module, and the Alpha Magnetic Spectrometer (AMS). In 2003, the National Research Council and the National Academy of Public Administration reported that NASA drastically reduced the overall ability of the ISS to support science, and that this reduction limited or foreclosed the scientific community’s ability to maximize the research potential of the ISS. NASA’s Plan to Support the Operations and Utilization of the International Space Station Beyond 2015 states that it would cost several billion dollars to reinstate the full scope of planned ISS facilities. Though the Vision changed and reduced the scope of NASA’s goals for its own research on board the ISS, Congress designated the ISS as a national laboratory in 2005 in an effort to increase utilization of the ISS for research. Congress also asked NASA to seek to increase utilization of the ISS by other federal entities and the private sector through partnerships, cost-sharing agreements, and other arrangements that would also supplement NASA funding of ISS research. According to NASA officials, this designation does not guarantee an appropriation specifically for ISS National Laboratory research. The ISS National Laboratory operates in conjunction with the ISS research programs of NASA and the international partners, and utilizes a portion of the USOS resource allocation, including crew time, facilities, and cargo launched to the station. As such, NASA conducts the research it sees as relevant to its mission, and the ISS can also accommodate users from outside of NASA who are not necessarily conducting research relevant to NASA’s Human Research Program or other NASA-sponsored research. NASA established the ISS National Laboratory Office in the spring of 2009; this office is part of the existing Space Station Payloads Office and as of April 2009 had five staff members. In May 2009, President Obama established the Review of U.S. Human Space Flight Plans Committee. Its stated goal is to provide an independent assessment of the nation’s planned human spaceflight activities and to ensure that that country is on “a vigorous and sustainable path to achieving its boldest aspirations in space.” The committee conducted an assessment of NASA’s plans, including plans for the ISS, and developed a number of possible options for the future of the U.S. space activities. In its summary report released in September 2009, the committee developed five options for NASA’s human spaceflight program, and of these options, three recommend extending the lifespan of the ISS until 2020. The committee wrote that it would be unwise to de-orbit the ISS after 25 years of design, development, and assembly and only 5 years of operations, and that the return on investment to both the United States and the international partners would be significantly enhanced by an extension of the ISS’s life. It is unknown at present which option will ultimately be selected, but the future utilization of the ISS depends on this decision. The ISS has been continuously manned since 2000, and in March 2009 the crew expanded from three to six. NASA’s primary objective for the ISS through 2010 is construction, so research has not been the main priority. Specifically, though the ISS facilities have been used for some research to date, new research capabilities are still being added and are awaiting launch and installation, and resources such as crew time, transportation, and facilities planned for the utilization phase have not been fully available. As such, research is being conducted at the margins of assembly and operations activities as time permits, while the crew on board performs assembly and operations tasks. NASA has identified 197 U.S.- integrated investigations that have been conducted on orbit as of April 2009, though 55 of these investigations were conducted on the Space Shuttle missions to the ISS instead of on the ISS itself (called sortie research). According to NASA, as of February 2009, U.S. ISS and sortie research have resulted in over 160 publications, including articles on topics such as protein crystallization, plant growth, and human research. According to NASA, there have also been approximately 25 technology demonstration experiments flown on the ISS during the assembly phase. Once construction is completed, NASA projects that its share of the ExPRESS racks will be less than 50 percent occupied by planned NASA research related to the Human Research Program and other NASA- initiated research, with the remainder available for other use. Any facilities that NASA does not plan to utilize are available to the ISS National Laboratory, and the system is flexible so that future rack space can be made available either to NASA-funded or ISS National Laboratory users up to the total capacity. These projections are based on NASA’s current ISS research budget and determinations of available resources based on the percentage of ISS resources that are allocated to NASA and the international partners according to established international agreements. Table 2 depicts the NASA projected occupancy of rack space for September 2010. Inside the ISS, there are many available interior, or pressurized, sites for research racks and other facilities, though not all available sites will ultimately accommodate a facility.