Why is the sun and moon the same size? Explore the six unsolved mysteries of the solar system. New stars were brewing in the inconspicuous parts of the galaxy 4.6 billion years ago, according to the British magazine New Scientist. Many galaxies are filled with hydrogen and oxygen, mixed with some solid dust. They begin to condense and form molecules. Unable to compete with its own weight, some newly formed molecular clouds collapse. In the heat and confusion, a star is born, which is our sun. Scientists don't know what triggered the process. After that, eight planets formed around the sun, each of which has a different relationship with the sun. Finally, life was born on earth, and then we humans. Here are the six unsolved mysteries of the solar system.
1. How is the solar system formed?
According to the theory of stellar evolution, the sun, like most other stars, is born of a cloud of interstellar gas. The cloud, which existed about 4.6 billion years ago, lies in the disk structure of the Milky way, about 2.5 billion kilometers from the center. Its volume is about 5 million times that of the sun, and its main component is hydrogen molecule. This is the solar nebula. After more than 40 million years of condensation, a star was born in the center of the nebula, which is the sun. If you look at the planets in the solar system, do you think they belong to the same family? Are they adoption or kinship? The birth of the solar system reveals that they are compatriots of the same origin. They are all formed by the same molecular cloud that collapses into the sun.
You will also think about how these planets are dispersed in the solar system without any reason. The answer is: when the sun is formed, it engulfs nearly 99.8% of the debris cloud around it. According to the general picture, a thin disk of gas and dust is formed around the waist of the new star due to the gravitational action. The dust in this disk collides and solidifies with each other, forming larger objects. At the deepest part of this disk, hydrogen combustion from the sun causes sharp temperature rise around, so only high melting point materials such as metals and silicate minerals can exist in solid form. Only when the objects in this area reach a certain shape, can they form four major planets in the solar system: Mercury, Venus, earth and Mars.
In addition, some areas of the solar system are below freezing point, and methane and water also exist in solid form. At this time, the planets that are being formed grow larger enough to begin to coexist with gas molecules and eventually form gas giants - Jupiter and Saturn. If it cools down further, it will form
Ice giants - Uranus and Neptune. That's why scientists expect these planets to have solid cores under their liquid shells.
2. Why is the sun as big as the moon in the sky?
The sun is about 400 times larger than the moon, but it is also about 400 times farther away from us than the moon. So they look the same size in the air.
3. Where is Planet X?
If we say that the solar system is a delicate structure, we have reason to speculate where all its components are located, but it is said that in the dark area of the solar system, there is an unknown world lurking there - Planet X, a frozen celestial body may be about the size of Mars or earth.
4. Where do comets come from?
People have been speculating about the origin of comets for millions of years. The theoretical origin of comets is the Oort cloud and the Kuiper belt, but these speculations are not tenable at present. In theory, the Oort cloud is a rock cloud made of ice about 7.5 trillion kilometers away from the sun. It may be the source of long-period comets. Long-period comets refer to comets that take more than a century to perfect their orbits. It was once thought that this area was also the original origin of short period comets, but a large number of analysis shows that this guess is impossible at all. About 20 years ago, it was thought that the Kuiper belt, which is about 4.6 billion miles (7.5 billion kilometers) away from the sun, might be the origin of short-period comets. Jewitt explained: 'but the results of the last few years of research cast doubt on that. Maybe this is the origin of other comets that we are going to find now. '
5. Is our solar system unique?
Since the first discovery of planets orbiting another star in 1992, 280 alien star systems have been identified, but most of them are not like our solar system at all. Last July, a new study showed that our solar system is indeed very rare and unique.
6. How will the solar system end?
Our sun will die, about six billion years ago. According to scientists, the sun is a common star in the Milky way, 1496 million kilometers away from the earth, with a diameter of 1.392 million km (about 109 times the diameter of the earth). The average density of the sun is 1.409 g / cm3, the surface temperature is 5770 ℃, and the center temperature is 15 million ℃. According to scientists' calculations, the sun is also the largest planet in the solar system. It has 99.8% of the total mass of the solar system, which is about 330000 times the mass of the earth. The structure of the sun is divided into nuclear reaction zone, troposphere and atmosphere. Among them, the core area constantly carries out thermonuclear reaction, and the energy generated is radiated to space, which becomes the main source of light and heat on the earth. The mass of the sun is composed of 75% hydrogen and 25% helium. At the same time, there are different rotation periods in the outer layer of the sun: 25.4 days in the equator; 36 days in the polar region. This strange phenomenon is due to the fact that the sun is not a solid sphere like the earth, and similar situations can be seen on gaseous planets. When the sun is destroyed into a white dwarf, the earth will no longer exist.