Final answer:
The nebular hypothesis suggests that the solar system formed from a collapsing cloud of gas and dust, leading to the formation of the Sun and planets roughly 4.5 billion years ago. This concept fits into a broader understanding of an evolving universe, as evidenced by the discoveries of Edwin Hubble and the formation of the Big Bang Theory.
Step-by-step explanation:
The nebular hypothesis is a scientific model that explains the formation and evolution of our solar system. This hypothesis suggests that about 4.5 billion years ago, the solar system was nothing but a gigantic rotating cloud of gas and dust, called the solar nebula. Under the force of gravity, this nebula collapsed, causing the material within to become more concentrated and hotter at the center, leading to the vaporization of most solid materials. Eventually, this process resulted in the creation of the Sun and the surrounding planetary system.
It's important to recognize that this hypothesis highlights a dynamic and evolving universe. One historical perspective that emphasizes this point is Edwin Hubble’s discovery in 1925 that nebulae, like the Great Andromeda Nebula, were actually distant galaxies, indicating an expanding universe. Later, the formation of the Big Bang Theory, or the hypothesis of the primeval atom, arose from observations and theories by Georges Lemaitre and Albert Einstein's work in relativity, reinforcing the idea of an ever-changing cosmos.
The nebular hypothesis fits within a larger context of astronomy that adapts as new discoveries are made. It's a cornerstone in our understanding of how celestial bodies like planets, moons, comets, and asteroids formed from the accumulation of dust and gas, a process involving condensation and accretion in a protoplanetary disk. This model aligns with evidence from studies of meteorites, the composition of planets, and the conservation of angular momentum in a developing solar system.