Final answer:
Rotation played a key role in shaping the solar system's formation by causing the solar nebula to flatten into a disk, due to the conservation of angular momentum, where planetesimals and eventually planets formed.
Step-by-step explanation:
The role that rotation played in the formation of the solar system, as described by the Solar Nebula Theory, is a fundamental aspect of how our solar system came to be. When the solar nebula began to collapse under its own gravity, conservation of angular momentum caused the nebula to rotate faster — a concept similar to a figure skater pulling her arms in to increase her spin rate. This increasing rotation rate caused the nebula to flatten out into a disk, with faster-spinning material at the equator creating a flat disk around the central concentration of mass which would become the Sun.
Within the solar nebula, the varying speeds of rotation meant material near the poles fell directly into the central mass, while material further out formed a protostellar disk where planetesimals began to coalesce, leading to the formation of planets. The disk also stabilized due to mechanisms like turbulent motions and magnetic fields within it, which can drain away some angular momentum, allowing more material to fall into the growing star.
In summary, rotation played a critical role in shaping the solar system's formation by creating the flattened, rotating disk of material within the collapsing solar nebula where planets and other bodies eventually formed. Regularities among the planets in our solar system lend credibility to this theory, and astronomical observations of other star systems with circumstellar disks support the idea that similar processes are at work elsewhere in the universe.