The Solar System Formation

Theories during the formation of the solar system:

According to the conventional big bang model of cosmology, time and the cosmos originated as a singularity roughly 14 billion years ago. Our cosmos began with the Big Bang, an explosion of space itself. Space expanded, the universe cooled, and the simplest elements were created, starting from extraordinarily high density and temperature. Gravity brought matter together throughout time to build the first stars and galaxies. Researchers have discovered for the first time that some of the heavier elements in the periodic table are generated when two neutron stars collide and burst cataclysmically. Light elements such as hydrogen and helium were generated during the Big Bang, while heavier metals such as iron are created by fusion in the centres of stars.

There are five theories behind it:

1. The Accretion theory
2. The Protoplanet theory
3. The Capture Theory
4. The Modern Laplacian theory 
5. The Modern Nebular theory

1. The Accretion theory:

The accretion theory states that particles slowly gathered together to form asteroids, planets, and even stars after the big bang. This occurs when a cloud of gaseous material and dust condenses into an accretion disc, which acts as a catalyst for the development of a solar and the remainder of a galaxy. Otto Schmidt, a Soviet planetary scientist, proposed a novel type of dualism theory in 1944. Cool thick clouds are known to exist in the galaxy based on telescopic measurements, and Schmidt argued that a star passing through one of these clouds would acquire a dusty-gas envelope.

The core accretion model is the first. The solar system, according to this model, was once a cloud of dust and gas known as a solar nebula before the Earth was formed. As the nebula began to spin, gravity caused the components to collapse in on themselves, forming the sun in the centre.

The word accretion comes from the Latin (accretio — accretere), and it refers to a progressive rise in size due to external addition or accumulation. In astronomy and planetary physics, accretion refers to the collecting of surrounding gas and objects (of smaller size) by gravity, resulting in an increase in the mass of a celestial object.

In planetary science, accretion is the process through which solids clump together to create larger and larger objects, culminating in the formation of planets. A disc of gas and minute solid particles with a total mass of about 1% of the gas mass are the starting circumstances.

The core accretion theory explains how our planet and solar system came to be. It shows how planets become multi-layered as they progress from the inner terrestrial planets to the outer gaseous planets. Earth is assumed to have been shock-heated during its accretion by impacts from meteorite-sized bodies and larger planetesimals. When a meteorite collides with the ground, the heat is concentrated near the impact site, allowing it to radiate back into space.

Any theory that claims the earth was formed by the progressive accumulation of solid bodies, such as meteorites, that were once rotating about the sun but were brought to the earth by gravitation.

2. The Protoplanet theory:

In astronomical theory, a protoplanet is a hypothetical eddy in a swirling cloud of gas or dust that condenses into a planet during the creation of a solar system. W. H. McCrea suggested the protoplanet hypothesis in 1960, 1963, and 1978, according to which the Sun and planets each coalesced from stuff within the same cloud, with the smaller planets eventually trapped by the Sun's stronger gravity. C. F. von Weizsacker introduced the revised theory, known as the protoplanet hypothesis, in 1944, and Gerald P. Kuiper refined it. Rapidly rotating nebulas have been discovered to create huge whirlpools or vortexes at various locations on the nebular material disc.

A cluster of stars is formed by a dense interstellar cloud. Dense patches grow and consolidate in the cloud; because the little blobs have random spins, the emerging stars will rotate slowly. The planets are tiny blobs that the star has captured. a hypothesized whirling gaseous mass within a vast cloud of gas and dust that spins around a solar and is thought to be the birthplace of a planet is called protoplanet theory.

According to the huge impact hypothesis, the Moon formed early in the Solar System's history as a result of a massive collision between Earth and a hypothetical protoplanet called Theia. Ceres, Pallas, and Vesta are the three protoplanets that have survived relatively intact in the inner Solar System.

According to the protoplanet idea, a large cloud of gas and dust rotated slowly in space about 5 billion years ago. The cloud has a diameter of at least 10 billion kilometres. The cloud shrank as time passed, perhaps due to its inherent gravitational attraction or due to the explosion of a passing star.

3. The capture theory:

Michael Mark Woolfson presented the capture hypothesis in 1964, claiming that the Solar System was generated by tidal interactions between the Sun and a low-density protostar. The gravity of the Sun would have sucked material from the protostar's diffuse atmosphere, which would then have collapsed to form the planets.

According to the capture theory, the Moon was produced elsewhere in the solar system as a wandering body (like an asteroid) that was captured by Earth's gravity as it passed close by. The accretion theory, on the other hand, proposed that the Moon was formed at the same time as the Earth.

Voyager 1 is the only spacecraft that has ever been in a position to photograph the whole solar system in one shot (or even a mosaic of 60 images).

Theory of capture—

The Moon, like many of Jupiter's moons, was caught by the Earth. Because a kidnapped moon would follow an elliptical orbit, this theory failed. The Moon, on the other hand, travels in a nearly round orbit.

4. The modern Laplacian theory:

Pierre-Simon Laplace, a French astronomer, and mathematician, proposed in 1796 that the Sun and planets began in a revolving nebula that cooled and collapsed. This nebula condensed into rings, which eventually became planets and a centre mass - the Sun, The Sun's sluggish spin could not be explained.

What is now known as Laplace's nebular hypothesis, a theory of the solar system's genesis? The planets, according to Laplace, condensed from the initial solar atmosphere, which once extended far beyond the present-day system's limits.

According to the contemporary interpretation, the core condensation comprises solid dust grains that cause drag in the gas as it condenses. The temperature of the core eventually rises once it has been slowed, and the dust evaporates. The Sun is formed by the slowly rotating core. Planets emerge from the cloud's rapid rotation.

5. The modern nebular theory:

Stars develop in huge and thick clouds of molecular hydrogen—giant molecular clouds, according to the nebular theory (GMC). Because these clouds are gravitationally unstable, stuff within them coalesces into smaller, denser clumps that rotate, collapse, and become stars.

Emanual Swedenborg, a Swedish physicist and theologian, advanced the theory that the Solar System arose from a nebula in 1734. Knowing Swedenborg's work, Immanuel Kant expanded on the notion and published it in his Universal Natural History and Theory of the Heavens (1755).

Our solar system was formed from a nebula cloud made up of dust and gas, according to the solar nebular hypothesis. The sun, planets, moons, and asteroids are thought to have formed from the same nebula roughly 4.5 billion years ago.

The nebular collapse resulted in three processes: 

1. The temperature has continued to rise. 
2. The solar nebula accelerated its spin. 
3. The disc of the solar nebula flattened.

There are some assumptions of the nebular theory:

1. The first is that all of the planets revolve around the same axis. 
2. The second is that they are all orbiting within 6 degrees of each other. 
3. The third is that all terrestrial planets, those within the Asteroid Belt's orbit, are rocky, whereas those beyond it are gaseous.

The solar nebular disc model (SNDM) or solar nebular model is a widely accepted current form of the nebular theory. It explained a range of Solar System features, including the planets' almost circular and coplanar orbits, as well as their motion in the same direction as the Sun's spin. This is the reason why nebula theory is accepted by scientists today. 

Conclusion:

The current scientific theory for the Earth's formation does a good job of describing not only the Earth's formation but also the Sun and all of the other planets. It's not so much "the Earth's origin story" as it is the origin story of the entire solar system.