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Headquartered in Cambridge, Massachusetts, the Smithsonian Astrophysical Observatory (SAO) is joined with the Harvard College Observatory to form the Harvard-Smithsonian Center for Astrophysics (CfA), where more than 300 scientists are engaged in a broad program of research in astronomy, astrophysics, Earth and space sciences, and science education. The Smithsonian Institution also continued to support national aerospace activities through research and education activities at the National Air and Space Museum in Washington, D.C.

Peering halfway across the universe to analyze light from exploded stars that died long ago, SAO astronomers and their Harvard colleagues have inferred that the cosmos will expand forever. Using the Hubble Space Telescope, these scientists have found that there is too little matter in the universe to halt its expansion. As a result, the universe should continue to balloon outward infinitely.

A team of astronomers, including scientists at SAO, discovered a disk of gas and dust around a nearby star that may be forming—or may have already formed—planets. The protoplanetary disk, about three times the diameter of Pluto's orbit around the Sun, surrounds a star roughly 220 light-years from Earth. The discovery was made with a NASA-funded instrument on a telescope in Chile at about the same time as an independent discovery was made by a second team using NASA's Infrared Telescope Facility in Hawaii.

Researchers from the CfA and the University of Arizona used the Hubble Space Telescope to study approximately two dozen examples of "gravitational lensing" in a project dubbed "CASTLeS" (which stands for the CfA-Arizona Space Telescope Lens Survey). Gravitational lensing is a phenomenon predicted by Einstein's Theory of General Relativity in which light rays emanating from a distant background object (such as a quasar) are bent by the gravitational field of a foreground object (such as a massive black hole or galaxy), thus distorting the appearance of the background object. The results will be used to learn more about the properties of distant galaxies and to determine the Hubble Constant—that is, the rate at which the universe is expanding. To illustrate gravitational lensing in a more familiar setting, the team started with a digitized photograph of the Smithsonian's Castle and then used computer software originally written for analyzing astronomical gravitational lenses to distort the image as if a black hole with the mass of the planet Saturn lay between the viewer and the Castle.

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