Only when we walk out of the earth can we know how small the earth is. In front of the vast universe, the earth is not even a small grain of dust. If the universe is compared to a living body, then the earth is at most a tiny cell on the living body.
After seeing the vastness of the universe, scientists will not doubt the existence of alien civilization. Scientists believe that in such a vast universe, the number of stars is too large to be counted, and the number of earth like planets such as earth is also impossible to estimate. In the face of huge data, it is difficult for us to question the existence of alien civilization.
Since the probability of the existence of alien civilization in the universe is basically 100%, why haven’t we found any? You know, as early as the 1960s, human beings began the “extraterrestrial civilization search project SETI”. In order to find the alien civilization, scientists use various methods to search, such as: Launch Voyager 1 and Voyager 2, let them carry the earth and human information to the depths of the universe; search for the possible existence of alien civilization signal in the universe; search for the possible existence of super building Dyson sphere and so on.
But after so many efforts, we still have nothing. Let alone the alien civilization, we have not found any of the simplest and primitive extraterrestrial life. What’s the matter? There are five possible reasons why human beings can’t find alien civilization, two of which may be the truth.
1、 The search scope is too small. In the 1960s, scientists proposed the Drake equation. According to this equation, the number of intelligent civilizations in the galaxy with a diameter of only 100000 light-years should not be less than 900. Some of these intelligent civilizations may have far more scientific and technological strength than human beings. Even if they have just entered the era of science and technology, they also have the primary ability to explore the universe.
If the alien civilization can get out of the parent star and start to explore the universe, it will inevitably leave some traces in the space, such as radio information or some powerful exploration spacecraft. The reason why we can’t find these things may be that the scope of human search is too small.
Although human beings have been able to walk out of the earth, we are still far from really exploring the starry sky. Our farthest probe is Voyager 1. Although it has gone out of the sunshine layer and entered the interstellar space, it still has a long way to go to get out of the solar system through the Oort cloud layer. Conservatively, it may take another 10000 years for Voyager 1 to get out of the solar system.
2、 Because of the speed limit, we can’t go out of the solar system to explore other galaxies, so it’s obviously impossible to rely on the spacecraft to search for alien civilization. Although Voyager 1 has gone a long way and carried CDs recording earth and human information, scientists have little hope for it to find alien civilization.
The spacecraft can’t find the alien civilization, so scientists focus on the space radio signal. As we all know, if an alien civilization enters the era of science and technology or even the interstellar age, then radio communication is inevitable. The more powerful the civilization is, the higher the energy level of radio will be, and the farther the transmission distance will be.
The vast universe looks very quiet, but behind the silence there are a lot of wireless signals constantly spreading. Most of these signals are sent out by various celestial bodies, such as pulsars, which can send out very regular radio pulse signals. Once scientists mistakenly thought that they were signals sent by alien civilization to human beings, so they were excited.
In addition to the signals from a large number of celestial bodies, there may be a small number of civilization signals in the universe. As long as we can find these signals, and successfully crack them, we can prove the existence of alien civilization, and according to the signals, we can also locate the star position where the alien civilization is located.
3、 Although it is a good way to search for alien civilization signals, some scientists have little hope for right or wrong. The reason for this is not that scientists believe that there is no signal of alien civilization in the universe. In the view of many scientists, it is basically certain that the signal of alien civilization exists in the universe.
So why don’t scientists have much hope for this? The reason is that we may not be able to receive these signals. Even if some alien civilizations send their civilization signals to human beings, it is futile that we can’t receive them. Maybe some people will say, why can’t we receive the signal of alien civilization?
The main reason may be that the signal patterns of the two civilizations are different. We should know that human civilization has formed its own unique characters and civilization forms in millions of years of evolution. Alien civilization is totally different from us. They must have experienced a long evolution and formed their own unique characters and civilization.
Will the development direction of science and technology be the same for two completely different intelligent civilizations? It may be said that scientific theory is a variety of laws that have existed in the universe for a long time. The rules and materials owned by the solar system will also exist in other galaxies. Although the universe is large, they all share the same physical laws and laws. Therefore, different civilizations may have different languages and cultures, but the scientific laws should be the same.
Is this kind of cognition correct? Generally speaking, it is true, but we should not forget that there is no end to the development of science, and there are many scientific laws of the existence of the universe, and there are many branches. All kinds of scientific theories mastered by human beings may be just one branch of many scientific theories. For example, in terms of wireless signals, different civilizations may have different branch theories, thus inventing different modes of radio signals.
Radio signal mode is different, even if they meet, no one may know who, naturally can not be found. And this possibility is very high, even within human civilization, the signal pattern is not one, and different patterns also have recognition obstacles. Not to mention that the signal pattern of alien civilization may be completely different from ours.
4、 Limited by the speed of light and space, we all know that the universe is so vast that we can’t imagine it. Even with our current observation capabilities, our observable range has reached 93 billion light-years. And this range may be just the tip of the iceberg in the vast universe.
In the universe, the speed of light and light year are the basic speed and distance units. In the eyes of human beings, the speed of light is the ultimate speed of an object, but this speed is only tortoise speed in the cosmic scale. At the speed of light, it takes us 100000 years to cross a small galaxy, let alone explore the universe.
Although the astronomical telescope observation distance is very far, tens of billions of light-years away stars can be observed, but it is not very easy to use in the observation of specific galaxies, planets and so on. If we want to really understand the environment of a planet in a galaxy, we can only go to the detector for close observation.
The existence of alien civilization is even more difficult for us to observe with telescopes. Even if there are alien civilizations in biling galaxy, which is only 4.2 light-years away from us, and there are a large number of spaceships sailing in the galaxy, we can’t see them at all.
Only by breaking through the speed limit of light and being able to reach other galaxies, can we really discover alien civilization through close-up exploration. Therefore, scientists believe that this principle may be the fundamental reason why human beings can not search for alien civilization. The speed of light and space not only limit the search for alien civilization, but also limit the contact with us.
5、 In the process of studying and exploring human history, scientists found some murals left by ancient civilizations. In these murals, some people or objects do not look like human beings or things on earth at all. For example, in some ancient murals, not only the human beings on the earth at that time, but also some non-human intelligent life are carved.
Scientists speculate that the intelligent life body carved on the ancient murals is totally different from that of human beings, which may be the alien civilization that visited the earth in ancient times. Ancient humans have no scientific guidance, and naturally they don’t know it’s actually the wisdom civilization of the planet, treating them as gods.
In addition to some people and objects suspected of alien civilization carved in these ancient murals, in some written records in the history of human civilization, there are also scenes of some suspected alien civilization spaceships coming to the earth, but the ancients at that time did not know what it was, so they recorded them as wonders.
If alien civilizations have been to the earth many times, why don’t they contact and communicate with human beings? It may be that the alien civilization thinks that the scientific and technological strength of human beings is too weak, there is no common language, and they don’t want to contact us. It may be said that primitive human beings in ancient times also had contact with alien civilizations, otherwise they would not know what aliens looked like, and they carved records on stone walls.
In fact, it’s easy to understand this point when we think about it carefully. For human beings in ancient times, extraterrestrial civilization was the gods in the sky. They came from the celestial world. People would respect extraterrestrial civilization as a belief, and there would be no danger. But will modern human treat alien civilization as a God?
Of course not, because human beings have entered the era of science and technology, and also know the existence of the universe. So for human beings, alien civilization is just the same wisdom civilization as ours, only technology is more advanced than ours. If the alien civilization comes into contact with us, it will be harmed by human beings. Therefore, the alien civilization would rather come into contact with primitive human beings in ancient times than with modern people.
These are five possible reasons why human beings can’t find alien civilization. As for which is the truth, we don’t know yet. Friends, if you have any special opinions, please leave a message below.