The search for extraterrestrial civilization started after human beings walked out of the earth. For more than half a century, scientists have not stopped exploring the footsteps of alien civilizations. Some people may not understand why scientists are so obsessed with finding alien civilizations? Does alien civilization necessarily exist?
Standing on the vast scale of the universe and the 13.8 billion years of the universe, it is difficult for us to doubt the existence of extraterrestrial civilization. Scientists also believe that the probability of the existence of alien civilization is basically close to 100%. As for why we are looking for alien civilization, one reason is driven by human curiosity, wanting to see if there are intelligent life like human beings in this universe, and What do aliens look like?
The other reason is that it has something to do with the progress of human civilization. We all know that although human beings are intelligent civilizations and have entered the age of technology, it is impossible for us to explore the universe with this bit of technology. According to the grading standards that scientists assign to cosmic civilization, human beings are not even a first-class civilization at present, and can only barely be counted as a 0.7-level civilization.
This is actually very understandable. Human civilization has only been formed for about 5,000 years, and technology has only developed for hundreds of years. Compared with the billions of years of life on Earth and the 13.8 billion years of the universe, this time is simply insignificant. If human beings can continue to develop science and technology, as long as we are given enough time, then we can grow into a first-class civilization, a second-class civilization, a third-class civilization, and so on.
However, it takes a very long time to achieve such a level increase, even at the current speed of human technological development. According to scientists’ estimates, it may take hundreds of years for us to grow into a first-class civilization. If we want to grow from a first-class civilization to a second-class civilization, it may take tens of thousands of years. With the continuous improvement of the level, the time required has also increased geometrically.
If the earth’s environment is always stable and the universe’s environment is always stable and safe, it will naturally give mankind a long enough time for development. However, with the continuous improvement of human cognition, we understand that the universe is not peaceful at all. In 1994, the earth almost ushered in the end. Fortunately, Jupiter blocked the front, so that the terrifying comet did not hit the earth.
But will such good luck always accompany the earth and mankind? We cannot believe in luck. We still need to work hard to develop technology quickly. Only when we truly become an interstellar civilization can we have the strength to deal with cosmic disasters. And relying on the development of mankind itself, it takes too long to become an interstellar civilization. What to do then? At this time, scientists thought of alien civilization.
From the time scale of 13.8 billion years in the universe, theoretically there should be some advanced civilizations that are tens of thousands, tens of millions, or even hundreds of millions of years more advanced than human beings. If we can get in touch with such a powerful civilization and get the technological help of alien civilizations, we may be able to transform humans from insects into dragons and interstellar civilizations. This will undoubtedly save humans at least tens of thousands of years of long development time. .
Therefore, although Hawking has repeatedly warned mankind to be vigilant against alien civilizations, he still cannot extinguish the enthusiasm of scientists to search for alien civilizations. There are two main ways for humans to find alien civilizations. One is to search for possible wireless signals of alien civilizations in the universe, and the other is to continuously observe and search for terrestrial planets that are very similar to the Earth through astronomical telescopes.
Based on the various conditions required for the birth of life on Earth, scientists judged that the planetary environment inhabited by alien civilizations should be almost similar to ours, with an atmosphere, a magnetic field, and liquid water on the surface. According to this standard, scientists have searched and found many terrestrial planets, but they have not found a planet that is completely similar to the earth’s environment. The gap between these planets and the earth’s environment is very large.
The environment of these planets is completely unsuitable for humans to survive. If an ecological planet that is exactly the same as the earth has not been found, does it mean that alien civilization does not exist? Of course, scientists will not believe that there is no doubt about the existence of extraterrestrial civilization. The reason why we have not found anything is that we are looking for the wrong way and direction.
Human beings look for alien civilizations based on the standards of the earth’s ecology, so aliens and humans will naturally have many similarities in the conditions needed for survival, such as needing water and breathing oxygen. But have we ever thought: It is possible that aliens breathe other gases instead of oxygen? Scientists speculate that it may be hydrogen.
Most life on the earth and the survival of human beings need sufficient oxygen. Without oxygen, we cannot live. This is the basic element for human survival on the earth. So how does the earth’s abundant oxygen come from? In fact, there was no oxygen in the early days of the earth. At that time, atmospheric carbon dioxide dominated the mainstream.
Early life on Earth was anaerobic because there was no oxygen. If this atmospheric structure did not change later, then life on Earth would have evolved through evolution, and the gas that it breathed would be carbon dioxide instead of oxygen. But this situation changed later. The emergence of a creature called “cyanobacteria” changed the earth’s atmosphere.
“Cyanobacteria” can release a large amount of oxygen and absorb carbon dioxide at the same time. As time goes by, the carbon dioxide in the earth’s atmosphere becomes less and less, and the oxygen becomes higher and higher, completing the replacement of carbon dioxide and oxygen. With abundant oxygen, the original anaerobic organisms continue to disappear, new life is born, and the breathing gas is oxygen.
The earth’s rich oxygen content was formed by a coincidence, so would the planet of alien civilization also experience the same atmospheric changes as the earth in its early days? I am afraid that it is unlikely. Each planet’s ecological environment will have its own evolutionary path. The inhabited planets of alien civilizations may also have their own unique evolutionary direction. The gas composition of the atmosphere and the atmosphere of the earth may be very large. s difference.
The composition of the atmosphere is different, the breathing gas may be different, we need oxygen, and aliens may need hydrogen. Why do scientists guess it is hydrogen? This is not a random guess, but has a certain basis. We all know that water is the source of life, but don’t forget that after water is electrolyzed, two gases are produced, one is oxygen, and the other is hydrogen. From the perspective of molecular weight, the hydrogen molecules produced by electrolysis are 2 and only 1 oxygen molecule.
In addition, what is the most abundant matter in the universe? I believe many people know that it is hydrogen. That’s right, hydrogen is the most abundant substance in the universe. Moreover, scientists have discovered that there are many planets in the universe, all with clouds, and these clouds contain a lot of hydrogen. On the whole, the probability of an alien civilization breathing hydrogen is still very high.
If we change the direction of searching for extraterrestrial civilizations, and choose the direction based on their need for hydrogen to breathe, we may be able to find that many terrestrial planets meet this standard. The discovery of alien civilizations in this way may be just around the corner. As long as we can reduce the scope of the universal existence of alien civilizations and roughly determine which galaxies have a high probability of having alien civilizations, then we can concentrate our strengths and conduct long-term observations to several key interstellar spaces. Research, perhaps there will be more important discoveries.
We must know that the universe is too big. If we don’t reduce the scope, the probability of finding an alien civilization is basically zero, because it is still a distant dream for human beings to realize interstellar exploration. If there are advanced civilizations in some galaxies, then we may also hope to observe some particularly magnificent civilized buildings, such as the Dyson Sphere.
Of course, the breathing of hydrogen by alien civilizations is only our guess. Life is mysterious and complicated. Life on Earth is just one of many life forms. Alien life and life on earth will inevitably have many differences. They may breathe oxygen just like human beings, they may breathe hydrogen that is ubiquitous in the universe, or they may breathe carbon dioxide or other gases.