Spectrum-X-Gamma is a long-delayed, Russian high-energy astronomy astronomy satellite; although constructed, no firm date has yet been set for its launch. Spectrum-X-Gamma carries a multinational of instruments including: JET-X, the Joint European Telescope, a British-Italian grazing-incidence X-ray telescope with CCD (charge-coupled device) detectors; SODART, a Danish-American-Russian telescope using grazing-incidence optics with proportional counters, solid state detectors, a spectrometer, and an X-ray polarimeter; FUVITA, a Swiss-Russian instrument consisting of four telescopes operating in the far ultraviolet region; and MART, an Italian-Russian high-energy X-ray telescope.