bolygóképzdést

Bolygóképződés refers to the process by which planets form from the accretion of dust and gas in a protoplanetary disk surrounding a young star. This process begins after the star has formed and a disk of material remains in orbit. Within this disk, gravitational instabilities and collisions cause dust grains to clump together, forming larger bodies called planetesimals. These planetesimals, which can range in size from kilometers to hundreds of kilometers, continue to collide and merge, gradually growing into protoplanets.

The composition of the protoplanetary disk plays a crucial role in determining the type of planet that forms. Closer to the young star, where temperatures are higher, only rocky and metallic materials can condense, leading to the formation of terrestrial planets like Earth and Mars. Further out in the colder regions of the disk, volatile compounds like water, methane, and ammonia can condense, allowing for the formation of gas giants such as Jupiter and Saturn, and ice giants like Uranus and Neptune. These outer planets often accumulate large amounts of gas through accretion, forming their massive atmospheres.

Over millions of years, the remaining gas and dust in the protoplanetary disk are either incorporated into planets, ejected from the system, or form smaller bodies like asteroids and comets. The final stage of bolygóképződés involves the gravitational interactions between the forming planets, which can lead to orbital migrations and the clearing of the remaining debris, resulting in the stable planetary system we observe today.