disk instability theory

Disk instability theory explains how planets form from a rotating disk of gas and dust around a young star. When regions of this disk become dense enough and cool sufficiently, gravity can cause these areas to rapidly collapse and clump together, forming new planetary bodies. This process allows planets to develop quickly, especially massive ones like gas giants. It contrasts with the slower core accretion model, providing an explanation for the existence of large planets that appear to have formed early in a star system's development.