The birth of the modern widely accepted theory of planetary formation – the solar nebular disk model (SNDM) – is due to the Soviet astronomer Victor Safronov. His book "Evolution of the protoplanetary cloud and formation of the Earth and the planets", translated to English in 1972, had a big effect. In this book almost all major problems of the planetary formation process were formulated and some of them solved. Safronov's ideas were further developed. There are still quite a few aspects of the Solar System which need to be explained. 