Only when we truly walk out of the earth can humans know how small the earth is. In front of the vast universe, the earth is not even a small dust. If the universe is compared to a living body, then the earth is at best a tiny cell in this living body.
After seeing the vastness of the universe, scientists basically do 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 terrestrial planets like the 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 an alien civilization in the universe is basically 100%, why have we not found even one until now? We must know that mankind started the “Extraterrestrial Civilization Search Project SETI” as early as the 1960s. In order to find alien civilizations, scientists use various methods to search for them, such as launching Voyager 1 and Voyager 2 to bring information about the earth and humans to the depths of the universe; searching for possible aliens in the universe Civilization signals; search for possible super-building Dyson balls and so on.
But after so much effort, we still got nothing, not to mention alien civilization, it is the simplest and primitive extraterrestrial life, and we have not discovered anything. What is going on? There are 5 possible reasons why humans cannot find an alien civilization, two of which may be the truth.
1. The search range is too small. In the 1960s, scientists proposed the Drake equation. According to this equation, the number of intelligent civilizations in the Milky Way galaxy with a diameter of only 100,000 light-years should not be less than 900. Some of these intelligent civilizations may far exceed the scientific and technological strength of human beings. Even the civilizations that have just entered the technological age, they also have the primary ability to explore the universe.
Alien civilization can get out of the parent star and begin to explore the universe, so 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 human search range is too small.
Although human beings have been able to get out of the earth, we are still far from truly exploring the starry sky. Our farthest probe is Voyager 1. Although it has left the insolation layer and entered the interstellar space, it still has a long way to go before passing through the Oort clouds and really getting out of the solar system. It is conservatively estimated that it may take 10,000 years for Voyager 1 to get out of the solar system.
2. Mankind’s search method is wrong. Due to the speed limitation, we cannot go out of the solar system to explore other galaxies. Therefore, it is obviously impossible to rely on exploration spacecraft to find alien civilization. Although Voyager 1 has gone very far and also carries a compact disc that records information about the Earth and human beings, scientists basically have no hope for it to find an alien civilization.
The spacecraft cannot search for alien civilizations. Scientists have focused their expectations on the radio signals of the universe. We all know that if an alien civilization enters the age of technology or even the interstellar age, then radio communication is inevitable, and the stronger the civilization, the higher the energy level of the radio, and the farther the distance will be.
The vast universe looks very quiet, but behind the quiet there are a lot of wireless signals constantly spreading. Most of these signals are sent by various celestial bodies, such as pulsars, which can send out very regular radio pulse signals. Scientists once mistakenly thought that they were signals sent to humans by alien civilizations, and were excited.
In addition to 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 search for these signals and successfully crack them, then we can prove the existence of alien civilizations, and we can also locate the starry sky where the alien civilizations are based on the signals.
3. Humans cannot receive signals from alien civilizations. Although searching for signals from alien civilizations is a good way to find them, some scientists have no hope of being right or wrong. The reason for saying this is not that scientists believe that there are no signals of extraterrestrial civilization in the universe. In the eyes of many scientists, the existence of signals of extraterrestrial civilization in the universe is basically a certain thing.
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 there are alien civilizations sending their civilization signals to mankind, it is futile if we cannot receive them. Some people may say, why can’t we receive the signals of alien civilizations?
The main reason may be that the signal patterns of the two civilizations are different. It is important to know that human civilization has formed its own unique writing and civilization form over millions of years of long evolutionary evolution. Alien civilizations are completely different races of life from us, and they must have undergone a long evolutionary evolution, and must have formed their own unique characters and civilizations.
Will the direction of technological development of two completely different intelligent civilizations be the same? Some people may say that scientific theories are various laws that have already existed in the universe. The rules and matter possessed by the solar system will also exist in other galaxies. Although the universe is large, they all have common physical laws and laws. Therefore, the different civilization languages and cultures may be different, but the scientific laws should be the same.
Is this perception correct? Generally speaking, it is correct, but let us not forget that there is no end to the development of science, and there are many scientific laws that exist in the universe, and there are many branches. The various scientific theories that humans now master 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.
The radio signal patterns are different. Even if they meet, no one may know the other, and naturally they will not be able to find it. And this possibility is very high. Even within human civilization, there is not one signal pattern, and different patterns have recognition barriers. Not to mention that the signal patterns of alien civilizations 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 the current human observing capabilities, our observable range has reached 93 billion light-years. And this range may be just the tip of the iceberg of the vast universe.
In the universe, the speed of light and light years are the basic speed and distance units. In the eyes of human beings, the speed of light is the limit speed of objects, but this speed is only the speed of the tortoise on the scale of the universe. Flying at the speed of light, it would take us 100,000 years to traverse a small galaxy, let alone explore the entire universe.
Although the observation distance of the astronomical telescope is very long, and stars tens of billions of light-years away can be observed, it is not very useful for observing the conditions of specific galaxies and planets. If we want to truly understand the environment of a certain planet in a galaxy, we can only go to the probe to observe closely.
It is even more difficult for us to observe the existence of alien civilizations with telescopes. Even if there are alien civilizations in the Territory galaxy, which is only 4.2 light-years away, and there are still a large number of spacecraft sailing in the galaxy, we simply cannot see it. Arrived.
Only by breaking through the limit of the speed of light and being able to reach other galaxies, may it be possible to truly discover alien civilizations through close-range detection. Therefore, scientists believe that this principle may be the fundamental reason why humans cannot search for alien civilizations. The speed of light and space not only restrict humans from searching for alien civilizations, but also restrict alien civilizations from contacting us.
5. Alien civilizations deliberately do not contact humans. Scientists have discovered some murals left by ancient civilizations in the process of researching and exploring human history. In these murals, some people or things do not look like human beings and things on earth at all. For example, in some ancient murals, not only the humans of the earth at that time, but also some inhuman intelligent life.
Scientists speculate that the intelligent life forms carved on the ancient murals are completely different from human beings, and it may be the alien civilization that visited the earth in the ancient times. The ancient humans had no scientific guidance, and naturally they did not know that they were actually the intelligent civilizations of the planet, and treated them as gods.
In addition to some suspected alien civilization people and objects carved by these ancient murals, in some written records in the history of human civilization, there are also some scenes of suspected alien civilization spacecraft descending on the earth, but the ancients at that time did not know that. What are they, so I recorded them as spectacles.
If alien civilizations have been to the earth many times, why not have contact with humans? It may be that the alien civilization feels that the scientific and technological strength of human beings is too weak, and there is no common language, and they do not want to contact us. Someone may say here that primitive humans in ancient times had contact with alien civilizations, otherwise they would not know what aliens looked like, and they would even record them on the stone wall.
In fact, it’s easy to understand if you think about it carefully. For humans in ancient times, alien civilizations are gods in the sky. They come from the heavens. People will respect alien civilizations as beliefs, without the slightest danger. . But do modern humans treat alien civilizations like gods?
Of course not, because mankind has also entered the age of science and technology and has also learned about the existence of the universe. Therefore, for human beings, the alien civilization is just the same intelligent civilization as ours, but the technology is more advanced than ours. If an alien civilization comes into contact with us, it will be harmed by humans. Therefore, an alien civilization would rather have contact with primitive humans in ancient times than with modern people.