The nebular hypothesis is the most widely accepted model in the field of cosmogony to explain the formation and evolution of the Solar System (as well as other planetary systems). It suggests that the Solar System formed from nebulous material.The solar nebular hypothesis describes the formation of our solar system from a nebula cloud made from a collection of dust and gas. It is believed that the sun, planets, moons, and asteroids were formed around the same time around 4.5 billion years ago from a nebula.

Nebular Hypothesis

The nebular hypothesis is a widely accepted scientific theory that explains the formation and evolution of our solar system. It suggests that the solar system originated from a giant, rotating cloud of gas and dust known as the solar nebula. Over time, this nebula collapsed under its own gravity and formed the various celestial bodies we observe today, including the sun, planets, moons, and asteroids.

Formation of the Solar Nebula
The solar nebula is believed to have formed from the remnants of previous stars that exploded in supernovae. These explosions released vast amounts of gas and dust into space, which eventually came together due to gravitational forces. As the cloud of gas and dust collapsed, it began to rotate, forming a spinning disk-like structure.

Formation of the Sun
Within the center of the rotating nebula, the concentration of matter and gravitational forces caused the formation of the sun. As the gas and dust accumulated, the temperature and pressure at the core increased, triggering nuclear fusion. This fusion process led to the ignition of the sun, converting hydrogen into helium and releasing tremendous amounts of energy.

Formation of Planets
The remaining material in the nebula, called the protoplanetary disk, started to clump together due to gravitational forces. These clumps, known as planetesimals, gradually grew larger as they collided and merged with other planetesimals. Eventually, these planetesimals evolved into protoplanets, which continued to accrete matter from the surrounding disk.

Differentiation and Evolution
As the protoplanets grew in size, their gravitational forces became stronger. This caused the protoplanets to attract more material, including gases, rocks, and metals. Through a process called differentiation, the protoplanets separated into distinct layers based on their composition. The heavier elements sank to the core, while lighter materials formed the crust and atmosphere.

Final Stages
As the protoplanets continued to accrete matter, they eventually became the planets we know today. The solar winds from the newly formed sun blew away the remaining gas and dust in the protoplanetary disk, leaving behind only the solid planets and smaller celestial bodies such as asteroids and comets.

In conclusion, the nebular hypothesis provides a comprehensive explanation for the formation and evolution of our solar system. It describes how the solar nebula collapsed and formed the sun, planets, and other celestial bodies through processes such as accretion, differentiation, and the clearing of debris. This theory has been supported by various observations and simulations and is widely accepted by the scientific community.