Question

The ___ hypothesis describes how about 5 billion years ago, a cold cloud of gas and dust contracts, rotates, and flattens into a disk like shape resulting in the formation of our solar system.

Answer 1

The 'solar nebula hypothesis' describes the formation of our solar system when a massive cloud of gas and dust collapsed 4.5 billion years ago, formed a rotating disk, and condensation within it led to the birth of the Sun, the planets and other bodies.

Step-by-step explanation:

The solar nebula hypothesis describes the process by which our solar system was formed approximately 4.5 billion years ago. This hypothesis explains how a large cloud of gas and dust began to collapse under its own gravity, leading to an increase in rotation and resulting in a flattened, disk-like shape. As the material in this solar nebula condensed and heated up, it gave birth to our Sun at the center, while the remaining matter coalesced to form the planets, moons, asteroids, and comets that we observe today.

Planetesimals, which are small, solid objects, emerged within the rotating solar nebula and they later gathered to form the planets. Notably, a nearby supernova explosion is thought to have sent a shock wave that triggered this concentration of matter and increased the nebula's spin. Over time, accretion of material led to the differentiation of the planets and after millions of years of violent impacts, a relatively calm solar system emerged with the planets orbiting the Sun.