Solar system

How did the solar system form?

How did the solar system form?

It is difficult to specify the origin of the solar system. Scientists believe that it can be located about 4.650 million years ago.

There are some explanations on how our Solar System has been formed. One of the most accepted is the nebular theory formulated by René Descartes in 1644 and later perfected by other astronomers.

According to the version proposed by Kant and Laplace, an immense cloud of gas and dust contracted due to the force of gravity, probably due to the explosion of a nearby supernova. Because of the contraction, it began to spin at high speed and flattened out; Therefore, the resulting Solar System is more like a disk than a sphere.

How did the sun form?

Most of the matter accumulated in the center. The pressure was so high that a nuclear reaction began, releasing energy and forming a star. At the same time some swirls were defined that, when growing, increased their gravity and collected more materials at each turn.

There were also many collisions between particles and bodies in formation. Millions of objects approached and joined or collided with violence and broke into pieces. The constructive meetings predominated and, in just 100 million years, acquired an aspect similar to the current one. Then, each body continued its own evolution.

Formation of planets and satellites

The planets and most of their satellites were formed by accretion of matter that accumulated around the largest pieces of the proto-nebula. After a chaotic succession of collisions, mergers and reconstruction processes, they acquired a size similar to the current one and moved until they were in the positions we know.

The area closest to the Sun was too warm to retain light materials. That is why the inner planets are small and rocky, while the outer ones are large and gaseous. The evolution of the Solar System has not stopped, but, after the initial chaos, most of the materials are now part of bodies located in more or less stable orbits.

Any theory that attempts to explain the formation of the Solar System should take into account that the Sun rotates slowly and only has 1 percent of the angular momentum, but it has 99.9% of its mass, while the planets have 99% of the angular momentum and only 0.1% of the mass. One of the explanations argues that, at first, the Sun was much colder; The density of its materials was slowing its rotation, while warming up, until a certain balance was achieved. But there is more ...

Theories about the origin of the Solar System

There are five other theories or variations considered reasonable:

The accretion theory it assumes that the Sun passed through a dense interstellar cloud, and emerged surrounded by a wrap of dust and gas.

The Proto-planetary theory It says that initially there was a dense interstellar cloud that formed a cluster. The resulting stars, because they were large, had low rotation speeds, instead the planets, formed in the same cloud, had higher speeds when they were captured by the stars, including the Sun

The capture theory He explains that the Sun interacted with a nearby proto-star, taking matter from it. The low speed of rotation of the Sun is attributed to the fact that it formed before the planets.

The Modern Laplacian theory it assumes that the condensation of the Sun contained grains of solid dust that, because of the friction in the center, slowed the solar rotation. Then the temperature of the Sun increased and the dust evaporated.

The Modern Nebula theory It is based on the observation of young stars, surrounded by dense discs of dust that are slowing down. By concentrating most of the dough in the center, the outer pieces, already separated, receive more energy and slow down less, thereby increasing the speed difference.

Discover more:
• Origin of the Solar System, extended version - AstroMía
• The origin of the Solar System could be a giant and dying star
• Formation and evolution of the Solar System according to Wikipedia


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