The ancients also asked questions and speculated in this way, but the ancients did not have telescopes or towers built by their predecessors. Even if they are not nearsighted, they can find distant things with their eyes and can't break through the barrier of the earth's surface atmosphere. They can only vaguely find some high-brightness astronomical phenomena in the universe and record them in the torrent of history.
With the development of time, mankind has started the industrial revolution, and the progress of science and technology is getting faster and faster. Up to now, the world may have changed in almost a few short years.
In the last century, two world-wide wars broke out because of the innate inferiority of human beings. In the last war, Germany and its allies were defeated by the general trend. As the superpower of the victorious country, the United States and the Soviet Union took away Germany's more mature rocket technology.
It is also with the help of relevant technologies and researchers that in the 1960s, the United States and the Soviet Union competed in the space field under the situation of the Cold War.
At that time, space was a field that the whole world yearned for, but it was impossible to get involved for technical reasons. This is undoubtedly the best way for the United States and the Soviet Union to show their strength in such a field, so the two sides chased each other and invested state funds and energy to develop space technology.
In fact, the space race was also criticized by some people in later generations, but the goals of the American and Soviet governments were not simple, but the space technology they developed was very rich and practical, and later they made great contributions, and even many technologies are being used all over the world.
Not to mention that the United States is the only country that can send people to the moon, not even the moon, but also the only country that has landed on extraterrestrial objects. It launched Voyager 1 on September 5th, 977. Even today, or in the future, Voyager 1 is a man-made probe that sails farthest from the earth.
In fact, Voyager 1 was actually a member of mariner program at first, and it was 1 1. Finally, it took off outside the solar system and explored more distant and mysterious places.
At that time, Voyager 1 happened to meet the geometric arrangement of planets that only appeared once in 100 years, so it was arranged to visit Jupiter, Saturn, Uranus and Neptune, all of which belong to the outer planets of the solar system and are very distant gas giant planets in the revolution period.
If you usually visit these four planets, it will take at least 30 years. But because of this special opportunity, Voyager 1 and Voyager 2 only need 12 years.
However, after 1980, 1 1 months, because scientists wanted Voyager 1 to explore Saturn's moon Titan, Voyager 1 could not continue to visit the remaining Uranus and Neptune, so it was forced to stop and sail outside the solar system.
In 20 12, Voyager 1 came to the top of the heliosphere of the solar system and passed through the sphere formed by solar energetic particles and cosmic interstellar matter, but still did not fly out of the solar system.
So far, Voyager 1 is about 23.2 billion kilometers away from us. For 44 years, it has been flying outward without seeing the boundary of the solar system.
In fact, Voyager 1 has not even reached the outermost Oort cloud area, which is full of spherical clouds formed by comets attracted by the sun. These spherical clouds surround the solar system, and the maximum radius can reach 1 light-year.
At the speed of Voyager 1, it will take about 300 years to enter the Oort cloud outside the solar system. If you want to cross it and escape from the solar system completely, you may not be able to go out until 30 thousand years later.
This is enough to show that for human beings, our current scientific and technological means can't leave the solar system at all, and even our planetary exploration is quite limited. The technology of manned landing on the planet is only completed by the United States, and it is only the moon, the closest satellite to the earth.
Voyager 1 On the way to fly away from the earth,1February 4, 990, it once took a picture of the earth, that is, the "dim blue spot", after sailing for 13 years.
At that time, voyager 1 was far away from the earth, 6.4 billion kilometers away. Even in the captured image, the earth only occupies 0. 12 pixels in the whole photo, which is just a tiny "dim blue dot".
It is conceivable that the so-called world-dominated human beings are so insignificant in the solar system, and the so-called slogan of "conquering the universe" is so fragile and ridiculous.
In fact, the solar system where human beings live is only a small corner of the Milky Way. There are about 654.38+00 billion to 400 billion stars like the sun in the Milky Way. Older stars hover in the central region, while younger stars are distributed outside.
The Milky Way mainly has four spiral arms. The sun is located at the inner edge of the Orion arm between the two main spiral arms, about 26,400 light years away from the center of the Milky Way, and rotates around the center of the Milky Way at an orbital speed of 2 17 km per second.
From the point of view of the whole galaxy, we can't even find the position of the solar system. It's like a water molecule in the ocean and a dust in the desert.
Nevertheless, the Milky Way, which is extremely huge for the solar system, is actually just one of the larger galaxies in this galaxy group. In addition to the Milky Way, there are about 50 galaxies, which together with * * * form a relatively loose cluster of galaxies. Andromeda, which is about the same size as the Milky Way, is the largest galaxy.
The galaxy cluster is centered on the Milky Way, with a radius of more than 3 million light years and a total mass of 65,600 trillion suns. However, this is not the end of the story. This cluster is only a part of a local supercluster, also known as virgo supercluster.
The Earth is 60 million light years away from the center of this supercluster. In virgo supercluster, there are about 100 galaxy clusters similar to ours, which * * * form an irregular pancake shape, and the diameter of the coverage area even reaches 1. 1 100 million light years.
The Milky Way, which was originally huge in our eyes, has also become the same tiny dust, which is unremarkable in virgo supercluster. Among them, there are 47,000 relatively large galaxies similar to the Milky Way, and the Milky Way really has no ranking.
So is the Virgo supercluster big? In fact, virgo supercluster is only a part of Ranyakaya supercluster. There are more than 65438+ ten thousand galaxies in Raniacaya supercluster, which are like an incomparably huge network and connected with countless supercluster.
Virgo supercluster is only one of the largest clusters of galaxies, among which there are 300 to 500 known clusters of galaxies, perhaps more, which can only be discovered by humans now.
The Ranyakaya supercluster has reached 520 million light years. According to scientists' observation, there may be a huge gravitational force at the distance of about1.500 million to 250 million light years, which can attract all giant galaxy clusters, including virgo supercluster, and rotate around them. This is also called "Ju Yuan" by human beings.
Looking out, there is a supercluster complex called Pisces-Cetacea, which is also the largest structure in the universe discovered by human beings, with a length of 65.438+0 billion light years.
There are about 60 clusters in this complex, and even the mass of virgo supercluster where we are located is only 0.0 1% of it, and the Rania Kaya supercluster and four other supercluster * * form such a huge complex.
However, the Pisces-Cetacea supercluster complex is not the largest complex discovered by human beings. In addition, according to the existing technology, scientists have obtained five more exaggerated structures than the Pisces-Cetacea supercluster complex.
For example, the Great Wall of Si Long, a wall-like structure formed by galaxy clusters, is 13.7 light years long. The largest is Wuxian-Beiguan Left Great Wall, and the largest length is even about 654.38+0 billion light years. Humans can't even understand how it came into being.
So far, mankind has exhausted scientific and technological means. The theoretically observable diameter of the universe is 93 billion light years. In this range, there are even at least 2 trillion galaxies similar to the size of the Milky Way, but this is not all the space in the universe, but the space that can be observed under human science and technology.
This may just be a small corner of the vast universe, just like the earth is to the Milky Way and the Milky Way is to virgo supercluster. Every time we think this size is enough, we can always find more distant and amazing facts.
Scientists have found that the universe is still expanding, and there may be no boundaries at all, only endless width. Some scientists believe that there may be other universes besides our own, such as the Milky Way and Andromeda galaxy.
But what the universe looks like, human technology is too limited, we simply can't know. Our space technology has developed for only a few decades. Although the development is slow, it is also making progress.
We don't need to sell ourselves short, nor do we need to feel that the road ahead is bleak. Perhaps space technology is relatively backward now, but we also believe that one day after thousands of years, we will be able to break through the limit and explore deeper truth.