With the brain of wisdom, human beings have grown up step by step from the weak position of nature and become the new overlord of the earth. After the formation of human civilization, it took only 5000 years to enter the road of scientific development, which is a miracle.
Science and technology has led mankind to open the door of the new century and made human civilization leap forward one after another. It has not only made people’s quality of life higher and higher, but also realized people’s dream of flying to the sky in ancient times, and went out of the earth to explore the vast starry sky.
After human beings have the power of science and technology, they will not be reconciled to a small earth. At this time, we have greater ambition, that is, the star sea. Human beings expect that one day, we can become the overlord of the galaxy and the universe.
When we walk out of the earth and face the vast universe, we have to think about a problem: the possibility of the existence of alien civilization. From the perspective of the vast universe and the 13.8 billion year history of the universe, it is difficult to deny that alien civilization does not exist.
After a lot of observation, scientists believe that alien civilization exists, and the universe should be very lively. The existence of alien civilization for human hegemony, there will be many unknown variables, so exploring the universe is a very important task for us to explore the possible existence of alien civilization.
Only by learning more about alien civilization can we make our future road of dominating the starry sky more smooth. Although the imagination is beautiful, the observation results of reality surprise scientists. It turns out that the universe we see has no lively scene, and it is lonely everywhere. What’s the matter? Where has alien civilization gone?
It is inconceivable that the universe is so quiet. Scientists have calculated for a long time that there should be so many livable places in the universe that we can’t count them. Under the infinite cardinal number, there should be many alien civilizations in the universe, but why can’t we see any?
In this regard, scientists still don’t think that there is no alien civilization in the universe. The reason why we can’t find it is that our observation method and observation ability are limited. So scientists started the great extraterrestrial civilization search project half a century ago. The project seeks to find alien civilizations through various means, such as the launch of Voyager 1 and Voyager 2.
Both spacecraft carry a gold CD, recording the coordinates of the earth and human information. The Voyager spacecraft is constantly advancing outside the solar system, expecting to be discovered by alien civilization after it goes out of the solar system, so as to know the existence of the earth and human beings, and come to the solar system to contact us.
In addition to launching starships, scientists also search for possible alien civilization signals in the universe. If the alien civilization, like the human civilization, also entered the era of science and technology and went out of the parent star to explore the universe, then the extensive use of radio communication is inevitable. The speed of wireless signal transmission has reached the speed of light. If a powerful alien civilization in the universe has also discovered the earth, it may take the initiative to send signals to the earth.
As long as we can find such a signal, we can prove the existence of alien civilization by cracking it, and determine the location of the other side according to the signal source. Searching for mysterious signals in the universe is also the most successful way for human beings to search for alien civilization. Unfortunately, until now, nothing has been found.
In addition to the above two methods, another way to search for extraterrestrial civilization is to search for earth like planets in the galaxy that are very similar to the earth through telescopes. Scientists believe that the earth can become a living planet and give birth to human beings, which is related to the earth’s natural high-quality ecological environment. And every high-quality ecological planet can be easily seen as long as it stands in space.
There are eight planets in the solar system. If we compare them together, we can see from the appearance that the earth is so dazzling, emitting sapphire light. This is the unique style of life planet, so other planets in the universe that can give birth to civilization probably have the same beautiful and dazzling appearance.
These earth like planets, which are very similar to the earth, are more likely to have life and even intelligent civilization. On March 7, 2009, NASA launched the Kepler space telescope. This telescope is very powerful, its search range is very wide and accurate, and its method of finding planets is also very unique.
Kepler space telescope searches for planets through transit method. In short, it uses the light changes produced by the stars when the planets and stars overlap to judge whether there are planets near the star, the size and shape of the planet, the distance to the star, and the rotation of the planet. This method can be used for preliminary judgment.
During the nine-year operation of Kepler telescope, thousands of stellar systems have been observed and many planets have been found, including hundreds of earth like planets in habitable places. It can be seen that earth like planets are also very common in the universe. Some of these earth like planets are very similar to the earth. From the appearance, they are also very dazzling and beautiful. Scientists speculate that they may be life planets.
Of course, what scientists most expect is to discover alien civilizations. However, by observing and looking for earth like planets, we are not sure that there will be intelligent civilizations in a galaxy or a earth like planet. When scientists didn’t expect much from this method to find alien civilization, a major discovery made scientists hope again.
Kepler telescope in the process of looking for planets, found a special star, it is called “tubby star”, located in the constellation Cygnus, about 1500 light-years away from us. As we said earlier, Kepler searches stars by changing the brightness of stars. Under normal circumstances, even if dozens of planets gather around a star, its luminosity fluctuation range will not exceed 5%.
However, the “tabby star” has shown strange situation for many times. Its luminosity has changed greatly for many times, and the most severe one even darkened by 22%. This has never happened in other stars. What’s the matter? When this was first discovered, some scientists thought it might be caused by the cosmic dust blocking the stars.
However, this conclusion was quickly denied. If the cosmic dust obscures the light emitted by the star, then the cosmic dust will certainly heat up in the process of being illuminated by the light of the star. It will be easy to see them in the infrared observation instrument, but they have not been observed in reality.
If it is not for these natural phenomena of the universe that make tabby’s luminosity greatly weaker, then there may be only one result, that is, the conjectured Dyson sphere. The famous physicist Freeman Dyson proposed the “Dyson sphere” conjecture. He believed that when a civilization develops to the second level, due to the huge demand for energy, it is necessary to fully use the huge energy of stars. In order to make better use of the energy of stars, we need to build a huge structure to surround the stars and absorb energy. This device is the Dyson sphere.
If a star is surrounded by a giant device such as a Dyson sphere, it will naturally make the brightness of the star change greatly. It is this unusual change of light that has taken place on Tabby, and scientists speculate that a second-class civilization may have appeared, in the constellation Cygnus, which is about 1500 light-years away from the earth.
If there is a secondary civilization in tabby galaxy, is it a joy or a worry for human beings? The distance of 1500 light-years is actually a very short distance on the cosmic scale, which can not be crossed by human beings at present, because our civilization level is only 0.7, which is not even a level one civilization. However, for a second-class civilization, if it has mastered the interstellar navigation technology, even if it has not mastered the superluminal flight technology, then the basic subluminal flight can be achieved.
1500 light-years away, if you have sub light speed flight technology, it will take thousands of years. Maybe thousands of years is also a very long time in the short life span of human beings, but we should not forget that the power of science and technology is infinite. Human beings are constantly exploring genetic technology, and have made some achievements in longevity.
So the second level civilization naturally has more powerful life technology, and it’s not unusual to increase its life span to several thousand years. With the powerful scientific and technological strength of the second level civilization and the distance of 1500 light, they may have already discovered the existence of the earth. It is also speculated that the earth may be an intelligent civilization planet.
If the dark forest law exists in the universe, it means that human beings have made a sound in this forest, and other hunters may be on their way to us. Maybe in the near future, the spacecraft of tabby will come to the solar system. Is alien civilization coming to the solar system with nothing to do? Nature is not. It must have its purpose. Is it for the earth, a resource planet, or for human beings? Is alien civilization friendly or malicious to human beings?
All this is hard to say, so Hawking has repeatedly warned mankind not to look for alien civilization, because it is very unwise to take the initiative to expose human existence before human beings are really strong, which may bring devastating crisis to the earth and human beings.