Operating on behalf of NSF, the national community of astronomy researchers, and funding partners, NSF's Green Bank Observatory (GBO) enables leading edge research at radio wavelengths by offering access to telescopes, facilities, and advanced instrumentation to the global scientific and research community. GBO also provides research and educational opportunities through a variety of radio telescopes and facilities on site. GBO is located in Green Bank, West Virginia, on approximately 2,600 acres of federal land. GBO anchors and administers the National Radio Quiet Zone (NRQZ) where radio transmissions are limited by law. Having telescopes within the NRQZ allows detection of faint radio astronomical signals that would otherwise be overwhelmed by anthropogenic radio transmissions.
The main scientific instrument at GBO is the 100-m Green Bank Telescope (GBT) the world's largest fully steerable single-dish radio telescope, operating at frequencies from 0.2 GHz to 116 GHz. The GBT's large sky coverage, very high sensitivity, wide wavelength coverage, and extensive suite of instruments make it a powerful and versatile telescope which enables advances in virtually all areas of modern astrophysics. The GBT offers excellent complementarity and synergy with interferometric arrays, such as the Very Large Array, the Very Long Baseline Array, and the Atacama Large Millimeter/submillimeter Array by providing the larger context for studies requiring the high angular resolution of these facilities. It also plays a critical supporting role as a highly sensitive element of very long baseline interferometry, as well as a bistatic radar receiver for rapid and sensitive imaging of near-Earth objects and asteroids.
Other facilities at GBO include engineering laboratories and fabrication shops; a visitor and education center (known as the Green Bank Science Center); the 43-meter Telescope; the Green Bank Solar Radio Burst Spectrometer; the 20-meter Geodetic Telescope; the 40-foot Telescope; the Interferometer Range; on-site accommodation for visiting researchers, educators, and students; and previously operational telescopes.
GBO supports a broad user community and is available to all scientists based on the intellectual merit of the proposed studies, independent of institutional or national affiliation. Astronomy is an important element in meeting national goals related to diversity, science and technology education, and increased U.S. competitiveness. Consistent with these goals, GBO conducts an active program of education and public outreach. The Green Bank Science Center attracts nearly 50,000 visitors each year, and the various telescopes on site provide invaluable training opportunities for students, as well as science enrichment for a very wide demographic to enhance scientific literacy in the general public.
Until 30 September 2016, GBO was part of the National Radio Astronomy Observatory, which is operated and maintained under a cooperative agreement between Associated Universities, Inc. (AUI) and NSF. Since 1 October 2016, GBO has been operated and maintained as a standalone facility under separate cooperative agreements between AUI and NSF.