Formation of Terrestrial Planets from the Viewpoints of Astrophysics and Material Science – Formation of Planetesimals by Chemical Reactions at Contact Points between Solids

Abstract

a solar system from a viewpoint of chemical describes in this paper. When a celestial body becomes sufficiently large to hold hydrogen atoms via gravitation, the hydrogen rich environment increases the body's growth rate at a fast pace. This will correspond to a "gravitational collapse". Before nuclear fusion, the proto-Sun contained large amounts of solids. In this context, the iron currently contained in the Sun is 0.014% of the total mass. The mass of the Sun is about 333,000 times that of the Earth where the mass of iron in the Sun is 46.6 times that of the Earth. The large amount of material of core was released as meteorites by the nuclear fusion of the Sun. The meteorite is the most objects in the solar system. The Japanese Hayabusa 2 mission revealed the rubble-pile structure of asteroid 162173 Ryugu [7]. The gravity of this asteroid is extremely weak with an escape speed of 30 cm/sec. Such a small celestial body does not retain its structure by gravitational force, rather the lump of solid matter is formed into the relevant shape by short-range forces at points of attachment. 51 Pegasi b, is the first exoplanet and was discovered by M. Mayor, D.