The general term of the theory of the origin of the solar system nebula proposed in the 20th century
This entry is missing Overview , add relevant content to make the entry more complete, and it can also be upgraded quickly. Hurry up edit Come on! The modern nebula theory is the general name of the nebula theory of the origin of the solar system proposed in the 20th century.
- Chinese name
- Modern nebula theory
- Proposer
- Berkeley
The first two modern nebula theories were the electromagnetic force nebula theory of Norwegian scientist O.K. Birkland (1867-1917) in 1912 and the electric field nebula theory of Dutch meteorologist H.P. Berlag (1896-1968) in 1927. There are twenty or thirty modern nebula theories that have been put forward, but the relatively complete and valuable ones unanimously recognized at the 1972 international symposium are: (1) Swedish Alvin theory; (2) British Hoyle theory; (3) French Shazmann theory; (4) American Cameron Theory; (5) Soviet Safronov theory. Chinese astronomer Dai Wensai also put forward a characteristic modern nebula theory. According to the modern nebula theory, the original molecular hydrogen cloud collapsed under self gravity 4.6 billion years ago. The dense inner region first forms the protosun at the core. The outer region slowly evolved into a disk. The dust in the cloud is unevenly distributed, and the part with higher density forms a gravitational accretion center, which grows into star particles. The higher temperature of the inner solar system evaporates light compounds, and the solid stars composed of silicon and metal gradually gather terrestrial planet 。 Outer solar system Little evaporation and ice rich planetesimals form giant planets. The tidal force of primitive Jupiter prevented the formation of major planets in the main belt of asteroids. The remaining larger celestial bodies are either captured as satellites, or broken up by collision and catapulted to the distance by the giant planets. The solar wind generated after the start of the solar thermonuclear reaction has blown away the remaining hydrogen and helium clouds, as well as the angular momentum of the sun. The modern nebula theory is basically consistent with the actual observation of the solar system. 
