Function 250 includes federal funding for the broad-based scientific research and development programs of the National Aeronautics and Space Administration (NASA) and the National Science Foundation (NSF) and for the general science programs of the Department of Energy (DOE). (Federal research and development funding for other agency missions or areas, including defense, health, and agriculture research, is included in those respective budget functions.)

More than half of the funding in function 250 is devoted to NASA's space and science programs, including the International Space Station, the space shuttle, space-based observatories, and various robotic missions. NSF, which accounts for 24 percent of 2007 funding in this function, is the government's principal sponsor of basic research at colleges and universities. DOE's general science programs, which are funded at about $3.7 billion for 2007, support specialized facilities and basic research in such areas as high-energy and nuclear physics, advanced computing, and the biological and environmental sciences.

Most spending in function 250 is discretionary. Outlays declined slightly in 2006, but spending over the four preceding fiscal years grew at an average annual rate of 3 percent. In 2007, outlays are projected to reach almost $25 billion, an increase of 3.8 percent from the year before.

In 2006, the National Science Foundation (NSF) received $93 million to promote improved science and mathematics education in elementary and secondary schools. The NSF programs primarily support advanced teacher training and continuing education, but they also are used for development of instructional and assessment materials.

This option would eliminate funding for those efforts. Implementing this option would save $11 million in outlays in 2008 and $321 million over five years. (This option would not affect the Math and Science Partnership, which is included in the programs of the No Child Left Behind Act. NSF is a collaborator in that partnership, which complements the efforts of the Department of Education in meeting the act's goals for mathematics and science education.)

Proponents of this option argue that NSF's efforts duplicate the work of larger programs in the Department of Education and in state and local governments. The No Child Left Behind Act, for example, mandates the hiring of more highly qualified teachers in all fields (not just in science and mathematics), and it provides resources for developing teachers' skills. The act also requires school systems to undertake specific, systematic assessments of students' progress in reading, science, and mathematics in several grades. Currently, the Department of Education is spending $23 billion helping elementary and secondary schools to meet No Child Left Behind requirements, including those for science and mathematics achievement. In the 2002-2003 school year, state and local governments spent $400 billion on public elementary and secondary education, and many governments devote resources to improving the quality of training all their teachers receive, including their teachers of mathematics and science.

Opponents of this option argue that NSF leverages its small contribution by focusing on basic educational research while allowing other agencies to develop and implement programs that apply NSF's results. Thus, for example, NSF programs focus on providing professional resources for the instructors of science teachers, whereas the programs of the No Child Left Behind Act and the Math and Science Partnership implement quality improvement measures for the science teachers themselves. Furthermore, some note that current federal funding for teacher quality grants under the No Child Left Behind Act is inadequate.

On February 1, 2003, the space shuttle Columbia was destroyed during its reentry to the Earth's atmosphere. On January 14, 2004, the National Aeronautics and Space Administration (NASA) unveiled the President's long-term Vision for Space Exploration, which stated that the remaining space shuttle fleet would return to flight to finish construction of the International Space Station (ISS) by about 2010. U.S. involvement in ISS operations would cease in 2017, and the U.S. research agenda before that time would be refocused to explore issues associated with long-duration human spaceflight. NASA originally estimated that 25-30 shuttle flights would be needed to complete ISS construction. The agency has since scaled back its plans for the ISS and now estimates 15 shuttle flights will be needed to complete that project.

Under this option, the shuttle program would be terminated immediately and the ISS would remain in its current configuration, saving NASA $3.3 billion in outlays in 2008 and $24 billion through 2012, relative to the Congressional Budget Office's baseline projections. Access to the ISS would continue to be provided by the Russian Soyuz spacecraft.

One rationale in favor of this option is that, even though the shuttle program is significantly smaller than earlier planned, it still may be difficult to complete 15 shuttle launches before 2011. To do so would require three to four launches each year through 2010, whereas NASA has been averaging one to two flights annually since 2005. In addition, there are continuing safety concerns involving foam shedding and the absence of the backup orbiter recommended by the Columbia Accident Investigation Board. Another argument in favor of this option is that even if the shuttle were used to finish construction of the ISS, the reduced scope of the scientific activities now planned means that little would be gained by completing the station's assembly.

An argument against this option is that its adoption would abrogate promises the United States has made to its international partners to complete ISS construction. The shuttle is essential to this task; the European, Russian, and Japanese modules yet to be added to the station have been designed and manufactured for transport by the space shuttle. In addition, retiring the shuttle in 2008 might preclude the Hubble servicing mission or force it to be accelerated to 2007. Finally, early retirement would hamper NASA's ability to sustain the engineering workforce needed to support human spaceflight, including the workers who now conduct launch operations at the Kennedy Space Center.

On January 14, 2004, the Bush Administration announced its Vision for Space Exploration (VSE), which provides guidance for the activities of the National Aeronautics and Space Administration (NASA). The VSE states that the space shuttle should be retired by 2010, that a new crew exploration vehicle (CEV) should replace the shuttle by 2014, and that CEV lunar missions should begin by 2020. The lunar missions will be a stepping-stone for human exploration of Mars and other more distant parts of the solar system. To return humans to the moon, NASA has decided to develop two launch vehicles: a crew launch vehicle (CLV), which will lift the CEV into orbit, and a larger and more powerful cargo launch vehicle (CaLV), for launching the hardware and fuel the CEV will require. Both of these new launch vehicles would incorporate some components of the existing space shuttle. Development of the CEV, CLV, and CaLV is being funded and managed under NASA's Constellation Program.

Under this option, the schedule for the Constellation Program would be extended by five years, delaying the first human lunar mission to 2025. However, research and technology development would continue unchanged, and an additional $500 million would be allotted annually to maintain the manufacturing and technology base. The resultant savings in outlays would be $1 billion in 2008 and would total about $16 billion through 2012.

A benefit of this option would be the additional time NASA would have to consider different approaches to conducting human lunar missions. During the past two years, NASA has made design changes to the CEV, CLV, and CaLV in response to technical concerns and budgetary constraints. Some observers argue that the shuttle-derived approach NASA has chosen is neither the least costly nor the safest approach, and they cite the design changes as supporting evidence. Others argue that the VSE's schedule constraints do not allow enough time to address the limitations that NASA's choices for the CLV and CaLV might impose on its ability to achieve long-term goals for exploring Mars and other more distant parts of the solar system. Delaying the first human lunar mission to 2025 would allow these issues to be studied in greater detail; it also would provide more time to implement whatever approach was chosen.

There are at least two drawbacks associated with this option, however. A delay of five years in developing and operating the CEV, CLV, and CaLV would extend to almost a decade the currently planned four-year hiatus in manned space missions and it would hamper the nation's ability to transport crew to the International Space Station. Such a delay also might adversely affect NASA's ability to sustain the engineering workforce needed to support human spaceflight, including the workers who now conduct launch operations at the Kennedy Space Center.