Taking the solar system as an example, starting from the physical characteristics and processes, how

More than 10 billion years ago, two extremely massive black holes collided to cause a large **, forming a new universe --- our universe, and in the primordial gas cloud of the universe, the Milky Way was born. After a long process, one of those stars degrades to become the sun, and it throws out a large amount of burnt gas, which wanders in the icy interstellar space, and gathers into a large mass of constituent materials, mainly hydrogen and helium, as well as various other elements. Due to the gravitational pull, the large clumps of gas begin to condense into individual high-density clumps.

The agglomeration rate of individual clumps varies, and the volume of each clump is very large. Over time, some of the near-** parts of the clump begin to accelerate agglomeration and produce rotation. The Earth was formed, and it was born about 4.6 billion years ago.

Attracted by the gravitational pull of the sun, revolve around the sun. Some of the remaining gases in space continue to fall into the sun, and some of the heavier atoms condense into stars as they revolve around the sun, which are the nine planets and moons.

Four words: gravity.

The absolute most authoritative explanation.

A galaxy is made up of stars, dust, and gas bound together by gravity.

galaxies are made up of stars, dust, and gas that are gravitationally bound together.

The solar system is a collection of celestial bodies centered on the Sun and subject to the Sun's gravitational constraints. It includes eight planets (in descending order from closest to the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune), as well as at least 173 known moons, five identified dwarf planets, and hundreds of millions of small solar system bodies.

Chinese name: solar system.

Foreign name: solar system

Composition: Sun, planets and moons, comets, meteors, etc.

Disciplines: Astronomy, Solar System.

Number of large planets: 8.

Number of dwarf planets: 5 recognized.

Number of Satellites: The number is known to increase every year.

Total number of celestial bodies: Uncalculable (estimated in billions).

Central Celestial Body: Sun.

Zhuyin: tai yang xi

Planetary Judgment: Consider turning to the left or right hand of the Sun.

Solar system. Explanation of terms.

The Milky Way is a barred spiral galaxy with a diameter of 100,000 light-years and includes between 100 billion and 400 billion stars. The Sun is a typical star of the Milky Way, located on the branch cantilever Orion Arm, 10,000 light-years away from the center of the Milky Way, and the solar system moves at a speed of about 240 s and makes a revolution in 100 million years.

The eight planets in the solar system all orbit in a near-circular orbit in about the same plane, orbiting the Sun in the same direction. With the exception of Venus, the other planets have the same direction of rotation and revolution. Most comets orbit in the same direction around the Sun, most of them have elliptical orbits, and generally have a long orbital period.

Celestial bodies orbiting the Sun are divided into three categories: planets, dwarf planets, and small solar system bodies.

A planet is a celestial body that orbits the Sun and is massive enough.

This type of celestial body: has enough mass to make itself a sphere in shape;

Small celestial bodies capable of emptying adjacent orbits.

There are 8 celestial bodies that can be called large planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

On August 24, 2006, the International Astronomical Union redefined the term planets, excluding Pluto from the list of large planets for the first time and forming Pluto, Ceres, and Eris into a new classification: dwarf planets. Dwarf planets do not need to purge small objects from nearby orbits, other objects that could become dwarf planets are Sedna, Erkus, and Tronis.

From 1930, when it was first discovered, to 2006, Pluto was considered the ninth planet in the solar system. However, in the late 20th and early 21st centuries, many objects similar in size to Pluto were discovered in the solar system, especially Eris was more clearly pointed out to be larger than Pluto (according to data sent back by Travelers in 2015, Eris is still larger than Pluto), making Pluto's position seriously threatened.

Are there any theories about the origin of the solar system that could explain these three things?

1.The distribution of chemical composition between different planets. (The Sun contains small amounts of heavy elements, Venus and Earth contain large amounts of heavy elements, and Saturn and Jupiter also contain small amounts of this element.) )

This can be explained by the Lewis model, where the early solar system was a cloud of gas with an internal temperature higher than the outer temperature. In the inner area, only substances like metals and rocks can be condensed. Thus the planets inside (Mercury, Venus, Earth, and Mars) are mostly made up of metals and rocks.

When you move to a colder outer area, it becomes cold enough, like water ice, followed by ammonia and methane ice condensation.

**: An artistic imaginary diagram of a protoplanetary disk

The reason the outer layers of the gas giants (Jupiter, Saturn, Uranus, Neptune) are made up of lighter components is that these planets will soon be larger than Earth. There are two reasons, one of which is that the outer area is cold enough for the mass to condense.

**: Comparison of the 4 giant planets of the Solar System with the Sun (proportional).

Another reason: ice sticks together better than rocks and metals, so when ice that has congealed into small pieces hits other ice blocks, it tends to create larger pieces instead of breaking up like rocks. Out-of-band planets originate from large planets made up of ice and rock.

Their mass is large enough that gravity allows them to accumulate hydrogen and helium, while the mass of the planets in the belt is not large enough to support hydrogen and helium. They are also not able to reach the current huge proportions in size.

**: The cutouts in these models are meant to illustrate the interior of the giant planet. Jupiter shows that the core of the rock is buried deep inside the metallic hydrogen.

2.The upward direction of Venus's rotation around its axis. (as opposed to other planets).

The old view about Venus (clockwise from the north, not counterclockwise like other planets) is that the influence of the Sun's gravitational pull slows down until its rotation period is equal to its orbital period. This is known as "orbital spin resonance". Mercury has a slightly different type of orbital cyclotron resonance.

However, that doesn't explain why Venus rotates backwards.

**: A night sky by the sea**. A glimmer of light is on the horizon, and many stars can be seen.

Venus is in the center, brighter than any star, and its reflected light can be seen in the sea. This is above the Pacific Ocean, and Venus is always brighter than the brightest stars outside our solar system.

**: The thin, dusty red atmosphere of Mars as seen from space. At the bottom left is the plain of Algiers.

3.The division of kinetic energy (as far as I can remember, the kinetic energy of the sun is less than 2%)

Relevant knowledge

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.

**: Ring nebula, a planetary nebula that approximates what the Sun will be

1: Solid surface, Mercury, Venus, Mars, Moon, Pluto, etc. all have solid surfaces (of course, the Moon, Pluto are not planets).

2: Mass and size, the Earth ranks fifth in mass and volume among the eight planets in the solar system. That is, not too big, not too small.

3: satellite; Except for Mercury and Venus, the eight planets have more than one moon, even Pluto, which is not a planet, has a moon.

4: Atmosphere; Most of the planets in the solar system have atmospheres, and Mercury has no atmosphere due to its small mass. Venus has a mass of only 80 percent of the Earth, but an atmospheric pressure of more than 400 times that of the Earth.

5: Rotation; In fact, every planet has a rotation, it's just a matter of speed, and the fastest known star is a pulsar (a dead star) that can make more than 30 revolutions per second. Slow for example, Venus rotates slower than it revolves.

6: revolution; In the solar system, most planets orbit the Sun except for the Sun (except for a few comets).

7: Magnetic field; The Earth has a strong magnetic field, both Mars and Jupiter.