We are working on theoretical astronomy and astrophysics. It may often be imagined that an astronomer watches the dark sky every night through a telescope. Instead, we use papers, pencils and computers to carry out our research. Being motivated by the latest observational data, we are trying to extract the essence of various complicated astronomical phenomena. Occasionally we request telescope time to prove a theory. The development of astronomy is brought about by both theoretical and observational work. The objects we are investigating are diverse: moons, planets, stars, galaxies, clusters of galaxies, active galactic nuclei, large scale structures of the Universe, and the Universe itself. One of our major efforts is dedicated to numerical simulations. Unlike experiments in the laboratory, astronomical phenomena are usually impossible to examine from many viewpoints. Numerical simulations make it possible to investigate these phenomena in detail. We are using the CfCA supercomputer, which is among the best in the world, as a “Telescope for Theory” and producing the newest research results.