planetesimaalien

Planetesimal is a term used in planetary science to describe a solid object, typically of a few kilometers in diameter, that is thought to have been a precursor to a planet. These objects are believed to have formed in the protoplanetary disk surrounding a young star through a process of accretion. Initially, dust grains in the disk collided and stuck together, gradually growing larger. As these clumps increased in size, their gravitational attraction became significant enough to pull in more material, leading to the formation of planetesimals.

These planetesimals then continued to collide and merge over millions of years. Some collisions may have resulted in fragmentation, breaking the planetesimals apart, while others led to their growth. Over time, the largest planetesimals dominated the accretion process, sweeping up most of the smaller bodies in their orbital paths. This process eventually led to the formation of protoplanets, which are larger than planetesimals and are on their way to becoming full-fledged planets. The remaining planetesimals that did not accrete into planets or protoplanets are thought to have become asteroids, comets, or Kuiper Belt Objects, depending on their location and composition. The study of planetesimals is crucial for understanding the formation and evolution of planetary systems, including our own solar system.