SAO is Russia's main centre for ground-based space research. ... The basic instruments of the Observatory are the optical telescope BTA (Big Alt-azimuth Telescope) with a main mirror diameter of 6 m and the radio telescope RATAN-600 with the antenna diameter 600 m. Study of the Universe as a whole, analysis of non-stationary energy release in galactic and extragalactic objects of various types, investigation of evolution and chemical composition of our Galaxy and the nature of solar activity. ...