What theory says that objects in space developed from cooling?

The theory that suggests objects in space developed from cooling is known as the Nebular Hypothesis. This theory posits that the solar system formed from a rotating cloud of gas and dust, known as a solar nebula, which collapsed under its own gravity. As the material cooled, it began to clump together, forming the planets, moons, and other celestial bodies. This process of cooling and aggregation is fundamental to the formation of structures in the universe.