Hundreds of years ago, after tens of thousands of years of development, human civilization finally entered the road of technological development. With the help of science and technology, mankind quickly realized the dream of flying to the sky, and walked out of the earth to see the vast universe.
We often say: “The vision determines the pattern”, this sentence is very reasonable. When we were in the earth age, because we could not see the world outside the earth, our vision was limited to the earth, and the pattern was naturally very narrow. Standing on the earth and looking at the starry sky, in fact, it is the same way as the frog at the bottom of the well looking at the starry sky.
Only when we truly get out of the earth and free from the bondage of the earth can we get out of the earth’s well and see the vast world outside the well. At this time, human vision has undergone earth-shaking changes, and the pattern is naturally completely different.
Standing in the vast universe, we will see in this vast space with a dark background, there are countless fascinating scenery, a large number of stars, galaxies, etc. dotted with this vast space. And in the distant starry sky, there are countless mysteries waiting for us to decipher. When we appreciate the beautiful universe, we can’t help thinking about this question: Are human beings alone in the universe? Are there alien civilizations in the vast universe?
If we ask the frog at the bottom of the well: “Does there exist humans in this world?”, the frog at the bottom of the well may answer: “That’s impossible. In the world at the bottom of the well, there are only our frog family.” But one day, when the frog at the bottom of the well walked out of the well and saw the vast world outside the well, if you ask it the same question now, it will answer: “How can there be only the frog race in such a vast world outside the well?” .
The cognition change of the frog at the bottom of the well is naturally adapted to humans. Before humans left the earth, many people would deny the existence of extraterrestrial civilization, but when we went outside the earth, most people’s perceptions also changed. According to the change in sex, basically everyone believes that extraterrestrial civilization exists. Scientists are even more convinced of this.
But if we want to find human beings who truly believe in the existence of alien civilizations, we still need to truly find alien civilizations. Therefore, as early as 70 years ago, humans started the search for extraterrestrial civilizations just after they walked out of the earth. It is not easy to find extraterrestrial civilizations. Scientists use various methods to search for them.
More than 40 years ago, scientists discovered Voyager 1 and Voyager 2 spacecraft, which carried a golden optical disc that recorded human information and the coordinates of the earth, heading toward the depths of the vast universe. Scientists’ expectation for Voyager is to be able to get out of the solar system and be captured by alien civilizations, so that alien civilizations can come to earth to contact us through the information recorded on the disc.
However, as scientists later reconfirmed the scope of the solar system, there is no hope that Voyager will be able to search for alien civilizations. We must know that the solar system includes the Oort Cloud, which has a diameter of 20,000 lights, and it may take tens of thousands of years to fly out of the solar system at the speed of the Voyager. Such a long time is enough for human beings to grow into an interstellar civilization.
Another way to find extraterrestrial civilizations is through radio signals, which is currently the main way humans search for extraterrestrial civilizations. If extraterrestrial civilization has also entered the age of science and technology, and has even become a powerful interstellar civilization, then the application of radio communication is inevitable. As long as we can search for the mysterious signals in the universe, perhaps we can know the location of alien civilizations by cracking them.
In theory, this method is feasible, but to receive regular signals from alien civilizations, two important prerequisites need to be met. First, it must be ensured that regardless of the development of alien civilizations, they must use radio. communication method. If the alien civilization uses other types of communication, then we will not be able to receive such signals.
The second is that the alien civilization must actively send signals to the outside world. If the alien civilization considers its own safety and completely shields the signal within a limited range of the starry sky, then we will never receive such a signal. And this possibility is very large. You must know that the stronger the civilization, the more likely it is to understand the cruelty of the universe. If you accidentally send a signal to be discovered by a stronger civilization, it may bring destruction to your own civilization. disaster.
In addition, there is an important problem in receiving radio signals in the universe-“synchronicity”, which means that the signal receiving device must be in the same direction as the signal, so that the information carried by the signal can be restored to the greatest extent. And this requirement undoubtedly increases the difficulty of searching, after all, in a state of aimlessness, no one knows which direction the signal will be emitted from.
It can be seen that it is difficult to find alien civilizations whether it is Voyager searching for alien civilizations or by searching for signals of alien civilizations. Many scientists believe that the way humans search for alien civilizations may have been wrong. At this time, some scientists put forward a new idea. This idea is to look for the huge structures of alien civilizations that may exist.
Not long after human beings walked out of the earth, a large number of artificial satellites, spacecraft, space stations and other artificial devices appeared in orbits outside the earth. Interstellar civilizations that are far stronger than human beings will naturally build larger man-made structures in their own galaxies. As long as we can find such a building, we will naturally be able to find an alien civilization.
However, it is also very difficult to observe the possible existence of alien civilizations in the depths of the distant starry sky. For our astronomical telescope to observe such a building, there are two prerequisites. One is that the building must be large enough to be inconceivable with human technology. The other is that the building must be able to make the star’s brightness change significantly.
You know, with the current human technology, if the target object does not reflect the change in light, we will not be able to see it no matter how large it is. The celestial bodies that humans look for, whether they are stars or planets, basically use the transit method. That is, the brightness of the star is judged and searched. If a normal planet blocks the star, the brightness of the star will change to a certain extent. At this time, we can be sure that there are planets or other celestial bodies around the star.
But if it is a huge man-made building surrounded by a star, the light and dark changes of this star will be very obvious. There is a high probability that this obvious change in light and darkness will not be caused by celestial occlusion. It may be a giant man-made building. This kind of construction scientists call it Dyson sphere.
Alien civilization surrounds the stars with man-made buildings. Naturally, it is not to be idle, but to absorb the energy of the stars. We all know that with the rapid development of science and technology, the energy required by a civilization will become larger and larger, and traditional chemical energy can no longer satisfy the development of a civilization. At this time, if this civilization wants to continue to develop, it needs to use more powerful and sufficient energy.
The most universal and powerful energy source in the universe is naturally stars, which are equivalent to a nuclear fusion reactor, continuously releasing powerful energy. If mankind’s technological strength reaches the point where it can fully collect and apply solar energy, I believe it will also build Dyson spheres to surround the sun to absorb energy.
Humans will do this, so powerful alien civilizations will naturally do the same. Therefore, some scientists believe that searching for artificial structures such as the Dyson Ball that may exist in the universe is the correct way to find alien civilizations. Speaking of “Dyson Sphere”, we have to mention the “Tabby Star” 1400 light-years away from Earth. Because of its bizarre change in luminosity, it shows that there are huge objects nearby that can block the light it emits. Many scientists believe that the huge object blocking the light of Tabby may be a Dyson sphere structure.
Of course, this is a better way to find alien civilizations that humans can think of with current technology. With the rapid development of human science and technology, once we become an interstellar civilization in the future, with the ability of interstellar navigation. Finding alien civilizations is even simpler. We can send spacecraft to various galaxies to find them, so the possibility of discovering alien civilizations will naturally be higher.
It’s just that when human beings truly become a powerful interstellar civilization, they may be less courageous. The reason is that at that time, we have more and more knowledge of the universe. The possibility of the earth being exposed will also be higher and higher. Once we get out of the solar system, it means that we may come into contact with other alien civilizations. If we are unlucky and encounter a malicious civilization that is stronger than humans, then what awaits humans may be the end of civilization.