A powerful x-ray telescope in orbit around the Earth. Built by the National Aeronautics and Space Administration, it was launched and deployed by space shuttle Columbia on July 23, 1999. Named after the Indian-American astronomer Subrahmanyan Chandrasekhar, Chandra is unique because of its sensitivity and its extremely high precision mirrors. These features have made possible significant advances in astronomy—especially in relation to the life cycles of stars, the role of supermassive black holes in the evolution of galaxies, and the study of dark matter and dark energy.