The Crimean Astrophysical Observatory is a leading center for astrophysical research in Russia, located at Simeis in south Crimea, between Sevastapol and Yalta, and operated by the Russian Academy of Sciences. Its principal instruments are a 2.6-meter (102-inch) optical telescope, a 22-meter (72-foot) radio telescope used for observations in the millimeter-wave region, and a solar telescope.