View source for Solar System/Planet Formation and Structure

== Core Accretion and Disk Instability ==
The 2 main/most common theories for planet formation are disk instability and core accretion.

=== Core Accretion ===
Core Accretion is the theory that planets form from small particles gathering together and forming lumps that accumulate more and more mass. This process is slow, taking millions of years.

=== Disk Instability ===
Disk Instability is the theory that planets form from spinning disks of material that accumulates so much mass, it violently collapses on itself and forms a planet. This is a quick process, taking just thousands of years.