How did the sun form and get bigger?

Don't know what kind of getting bigger you're referring to?

If it refers to the natural enlargement of the sun towards the end of its life, it is because:

After fusion, the energy produced by the central nucleus is no longer enough to sustain its radiation, so the equilibrium is upset and gravity prevails. Stars with helium nuclei and hydrogen shells shrink under gravitational pull, increasing their density, pressure, and temperature. The combustion of hydrogen is pushed into a shell around the helium nucleus.

Since then, the process of star evolution has been as follows: the inner core shrinks, the outer shell expands - the helium nucleus inside the burning shell shrinks inward and becomes hot, while the outer shell of the star expands outward and keeps getting colder, and the surface temperature is greatly reduced. That is, there will be a natural light nuclear reaction, resulting in nuclear fission, so the sun will rely on this nuclear fission to resist its strong inward gravitational pull, expand outward, and engulf Mercury.

This brings us to the red giant phase of the star.

1. The Sun was formed about 100 million years ago in a cloud of collapsing hydrogen molecules.

2. The formation and evolution of the solar system began with the gravitational collapse of a small patch in a huge molecular cloud 4.6 billion years ago. Most of the collapsed mass is concentrated in the center, forming the Sun, and the rest is flattened to form a protoplanetary disk, which in turn forms planets, moons, meteorites, and other small solar system bodies.

3. According to the relative strength of solar activity, the sun can be divided into two categories: quiet sun and active sun. The Tranquility Sun is a theoretically assumed Tranquility spherically symmetrical hot gas sphere, whose properties vary only with radius and are uniform in either sphere, for the purpose of studying the general structure and general properties of the Sun.

4. Under this assumption, the Sun is composed of a core, a radiation zone, a troposphere, a photosphere, a chromosphere, and a corona in order from the inside out. Below the photosphere is called the interior of the Sun; Above the photosphere is called the solar atmosphere.

1. The Sun was formed about 100 million years ago in a cloud of collapsing hydrogen molecules.

2. The formation and evolution of the Taifang crypto-crypto yang system began with the gravitational collapse of a small piece in a huge molecular cloud 4.6 billion years ago. Most of the collapsed mass is concentrated in the center, forming the Sun, and the rest is flattened and forms a protoplanetary disk, which in turn forms planets, moons, meteorites, and other small solar system bodies.

3. According to the relative strength of solar activity, the sun can be divided into two categories: quiet sun and active sun. The Tranquility Sun is a theoretically assumed spherically symmetrical hot gas sphere whose properties vary only with radius and are uniform in either sphere, with the aim of studying the general structure and general properties of the Sun.

4. Under this macro assumption, the Sun is composed of the core, the radiation region, the troposphere, the photosphere, the chromosphere, and the corona in order from the inside to the outside. Below the photosphere is called the interior of the Sun; Above the photosphere is called the solar atmosphere.

The sun was formed in a collapsing cloud of hydrogen molecules.

After the Great **, hydrogen condensed in the universe, forming huge clouds, and a part of the hydrogen was released and floated in the Milky Way, and as time went on, these free floating hydrogen began to concentrate and form the sun. The Sun is a star and has a lifespan, which is roughly 10 billion years.

At present, the age of the sun is about 100 million years, and when all the hydrogen elements in the sun disappear in about 6 billion years, its core will collapse, the temperature will rise, and the earth will become too hot and life will become extinct. The Sun is the central celestial body of the solar system, and Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and various asteroids and meteors in the solar system revolve around the Sun. But the Sun revolves around the center of the Milky Way.

The process of solar system evolution

There are several theories for the formation of the solar system, one of which is the nebula hypothesis, which was independently proposed by Kant in 1755 and Laplace in 1796. Immanuel Kant believed that the solar system was formed 4.6 billion years ago by the collapse of a huge molecular cloud. The nebula was originally light-years in size and had several stars at the same time.

Elements traced back to ancient meteorites show that only the core after a supernova** can produce these elements, so the cluster containing the Sun must be in the vicinity of the supernova remnant.

The sun was triggered by a seismic wave from a supernova** that increased the density of nebulae near the sun, allowing gravity to overcome the expanding pressure of the internal gases and cause them to collapse. With the development of modern astrophysics and physics, especially the establishment of the theory of stellar evolution, the modern nebula theory was born, and gradually became dominant.

Based on observational data and theoretical calculations, the modern nebula hypothesis puts forward its main idea: the primordial nebula of the solar system is a molecular cloud of massive interstellar cloud disintegration, which rotates at the beginning and contracts under its own gravity, the central part forms the sun, and the outer part evolves into a nebula disk, and the nebula disk forms planets after the nebula disk.

The above content reference: Encyclopedia - Solar System.

The formation of the Sun is achieved through a complex series of astrophysical processes. According to scientific understanding, the formation of the sun goes through the following main stages:

1. Molecular cloud collapse: In galaxies, part of a huge molecular cloud begins to collapse due to gravity. This could be due to disturbances caused by nearby star explosions, supernova remnants, or other reasons.

2. Rotation and accretion disc formation: When the molecular cloud collapses, rotation begins to occur and a flat accretion disk is formed. The disc is composed of gas and dust, in which the matter gradually gathers towards the center.

3. Protoplanetary disk formation: The material in the center of the accretion disk is densely packed into a protoplanetary disk, also known as the protostellar disk. This disk-like structure is the raw material for the formation of the Sun's Shenpei system, planets, and other celestial bodies**.

4. Stellar nuclear fusion: In the region at the center of the protoplanetary disk, the density and temperature of matter gradually increase to reach the conditions for nuclear fusion. Nuclear fusion is the process by which the center of the sun produces energy. In nuclear fusion, hydrogen nuclei fuse into helium nuclei, releasing energy and light.

5. The formation of the sun: When the nuclear fusion process begins, the pressure and temperature of the star's core reach high enough that the sun begins to emit intense light and heat. This marks the completion of the formation of the Sun and the entry of the main-sequence star (a stage of evolution of the star).

These stages involve the gravitational collapse of matter, rotation, nuclear fusion, and other physical over-width and rough ranges. Throughout the process, the formation of the Sun is a general process of star formation, and other stars in the universe may also undergo a similar evolutionary process.

The heliocentric theory was proposed by Nicolaus Copernicus.

At the age of 40, Copernicus proposed heliocentrism, which changed man's view of nature itself. At that time, the Roman Catholic Church believed that Copernicus's heliocentric theory violated the Bible, but Copernicus still firmly believed in heliocentrism, and believed that heliocentrism did not contradict it.

In 1533, at the age of 60, Copernicus gave a series of lectures in Rome, and finally decided to publish it until his deathbed, but did not receive a book written by himself from the publisher until his death. Copernicus's "heliocentrism" corrected people's view of the universe. Copernicus was a giant of the European Renaissance.

Copernicus spent most of his adult life as a priest in the Cathedral of Ferauern. Copernicus was not a professional astronomer.

Copernican Doctrine:

While in Italy, Copernicus became acquainted with the doctrine of the Greek philosopher Aristarchus (3rd century BC) and was convinced that the heliocentric theory that the earth and other planets revolve around the sun was correct. Around the age of 40, Copernicus began circulating among his friends a short manuscript in which he gave a preliminary account of his views on heliocentrism.

After two years of observation and calculation, Copernicus finally completed his great work, The Celestial Sphere. The accuracy of the calculated values observed in the Treatise on the Movement of the Celestial Sphere is astonishing. For example, the time to obtain the sidereal year is 365 days, 6 hours, 9 minutes and 40 seconds, with an accuracy of about 30 seconds and an error of only one millionth.

The Sun is a very ordinary star. The Sun is just one of the countless stars in the vast universe, many of which resemble the Sun, but there are also some stars that are larger or smaller, cold or hotter than the Sun. In conclusion, the Sun is a modest of stars.

350 million years ago, when life on Earth first began, the sun was different from what it is now. On the surface, the sun was pale yellow, 8 10 smaller than it is now, and only 70 75 brightness is now. Since then, the sun has slowly become larger, hotter and brighter for 350 million years, but not as good as the "greenhouse effect" that has lasted only 1 or 2 centuries.

For the next 5 billion years, the Sun will remain stable. The sun may be slightly larger, slightly hotter and slightly brighter later than it is now due to the burning of hydrogen, after which, the earth will change a lot. After 5 billion years, the sun's helium nucleus grew larger and larger, eventually collapsing, burning to become carbon, and the hydrogen on the surface continued to be converted to helium.

The energy from the helium combustion reaction will extrapolate the photosphere and the Sun will turn into a red giant, swallowing up Mercury and Venus, and reaching Earth's orbit. The sun-red surface will remain, but it will get colder and colder. The Earth will still be melted by the heat of the sun.

As the nuclear reaction stops, the Sun becomes a white dwarf the size of the Earth. The diameter of the Sun will change from 1.29 million kilometers today to 321.9 million kilometers for red giants and more than 12,800 kilometers for white dwarfs. As the nuclear fuel runs out, the sun gradually cools, turning from white to yellow, then red, and finally to a dark star.

The solar system was formed 4.6 billion years ago with the formation of the sun. The solar nebula gradually condensed due to its own gravitational pull, and gradually formed a celestial system composed of multiple celestial bodies arranged according to certain rules. The members of the solar system include one star, nine planets, at least sixty-three moons, about a million asteroids, countless comets and interstellar matter, among others.

The Sun is an ordinary star in the Milky Way. According to the theory of stellar evolution, the Sun, like most other stars, was born from a cloud of interstellar gas. This gas cloud existed about 4.6 billion years ago in the disk-like structure of the Milky Way, about 2.5 billion kilometers from its center.

It was about 5 million times the size of the current sun, and its main component was hydrogen molecules. This is the "Solar Nebula". After more than 400,000 years of contraction and condensation, a star was born in the center of the nebula, which is the sun.

Shortly after the formation of the Sun, some of the gas and dust that remained around the Sun formed planets orbiting the Sun and many other solar system bodies such as asteroids and comets, including the Earth and the Moon.

Diagram of the positions of the nine planets of the solar system and the Sun. From left to right are the Sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto.

The sun is nothing special in the vastness of the universe. There are about 200 billion stars that make up the Milky Way, and the Sun is only one of them. The Sun is five billion years old and is in the middle of its life.

As the center of the solar system, all living things on Earth need the light and heat it provides, directly or indirectly, for their growth. The temperature of the sun's inner core is 15 million degrees Celsius, where hydrogen-helium fusion reactions take place. Nuclear fusion reactions consume about five million tons of matter per second and convert them into energy that is released in the form of photons.

It takes more than a million years for these photons to reach the surface of the sun from the center of the sun. After the photon travels from the center of the sun, it passes through the radiation belt, losing energy in collisions with atomic particles along the way. It then passes through the convection zone, where the photon's energy is absorbed by the hot gas, which transfers energy to the surface in the convection current.

By the time they reached the edge of the convection zone, the photons had cooled to 5,500 degrees Celsius. What we can see directly is the photosphere on the surface of the Sun. The photosphere is relatively active, with a temperature of about 6,000 degrees Celsius, which belongs to the "cooler" part.

There are undulating convection units called "grains of rice" in the photosphere. Each grain of rice is about 1,600 kilometers in diameter, and they are the culmination of the thermals that rise from the inside of the sun. It is in the constant convection activity that the sun releases the equivalent of 100 billion megaton nuclear bombs into space every second.

The sun dog is not just formed by the reflection and refraction of light, but is a bright round object on the halo chakra. On the halo, the sun dog can appear on one or both sides of the sun or moon.

Some gases in the universe are constantly shrinking under the action of their own gravity, and the gravitational work converts mechanical energy into internal energy, and the temperature of the gas continues to rise. Eventually, the temperature of the gas rises to a temperature where nuclear fusion can take place, nuclear energy is converted into light energy and internal energy, the star begins to glow, and a star is formed.