Scientists speculate that alien civilizations may have been to the earth. Is it true?/You don't say.

The earth is a living planet, and human beings are the only intelligent life on this planet. Mankind entered the era of scientific and technological development, and soon realized the dream of flying and walked out of the earth. Only when humans walked out of the earth did they realize the vastness of the universe and the smallness of the earth. At this time, people will think of a question: Is human being lonely in the universe? Will there be an alien civilization?

Scientists see farther and think more than we do. In the eyes of scientists, alien civilization should exist, so physicist Enrico Fermi put forward Fermi paradox in 1950, mainly studying and exploring the possibility of the existence of alien civilization. Scientists have also put forward various explanations for Fermi paradox.

Some scientists think that alien civilizations may be too far away from us, and it is impossible to come to earth without advanced starships, while others think that alien civilizations rarely enter space, and they may have destroyed themselves before entering space. There are still some people who think that alien civilization may have been to the earth, but there was no human being born on the earth at that time.

Some time ago, the Journal of Astrophysics published a new study on Fermi's paradox, supporting that alien civilizations may have visited the Earth. I believe many friends know that the universe is composed of countless galaxies, both celestial bodies and galaxies are actually in motion. The eight planets in the solar system move periodically around the star sun, while our solar system actually moves around the center of the Milky Way, but the movement period is very long, reaching hundreds of millions of years.

In the 4.6 billion years since the birth of the earth, the solar system has made 20 turns around the center of the Milky Way. In addition to the solar system, other galaxies in the Milky Way are also moving around the center of the Milky Way, so the distance between these galaxies and the solar system is constantly changing during the movement. Maybe at some point, the two galaxies will form a phase, which will be very close.

If there are other alien civilizations in the Milky Way, they have become interstellar civilizations, but they are not particularly advanced. Because the solar system is very far from their galaxy, although astronomical telescopes can find the solar system, they can't reach it. However, the motion of galaxies makes this impossible. When the two galaxies are getting closer and closer in the process of movement, alien civilization may come to the solar system and visit the earth.

The same is true for humans to send probes to Mars. Mars revolves around the sun, and its distance from the earth is changing. When Mars is far away from the earth, it is also the best time for human beings to launch probes. So there may have been alien civilizations visiting the earth in ancient times, but at that time, the earth may not have the birth of human beings.

If there is indeed an alien civilization in the Milky Way that has visited the Earth, and the visit time is the closest between the two galaxies in the operation process, then this civilization may have visited the Earth more than once. You know, in the 4.6 billion years of the earth, it has turned around the center of the Milky Way more than 20 times, and the distance between the two galaxies has been more than 20 times recently.

Of course, this is an ideal situation. Scientists believe that it is also possible that alien civilizations visited the earth and were later destroyed. It takes hundreds of millions of years for two galaxies to circle the center of the Milky Way, so it will take hundreds of millions of years for the two galaxies to be closest to each other next time. Whether a civilization can last forever is also unknown.

Life has birth and death, and so do stars. For a civilization, it may not last forever. At a certain stage, it may also be eliminated. This seems to be the law of the universe. In fact, it is not difficult to understand that when a civilization becomes an interstellar civilization, they will definitely not nest in a small galaxy, but go out of the galaxy to colonize and expand.

Once you have the ability of interstellar travel, your vision will be broadened and you may come into contact with other civilizations. Although this is an opportunity, it is also a risk. If there is the law of dark forest in the universe, civilizations may not live in peace forever, especially those that encounter aggression and malice, and may face the destruction of civilization.

Once a civilization has the ability of interstellar travel, it is possible to expose the coordinates and position of the parent galaxy when it is out of contact with alien civilizations. Once you encounter the concern of malicious civilization, it is possible to usher in interstellar war. Therefore, some scientists believe that interstellar wars may often occur in the universe, but human vision and technology are limited and cannot be reached.

Of course, with the rapid development of human science and technology, we will certainly be able to get out of the solar system in the future. Coupled with the periodic motion of galaxies, the solar system may be the closest galaxy to the actual existence of life planets. At that time, humans may also visit that galaxy or discover a life planet similar to Earth. That planet may have given birth to rich life, but it may not have given birth to intelligent life, or it may have had primitive intelligent life.

If the civilizations of both galaxies become interstellar civilizations, then the approach between galaxies may be a dangerous signal. For human civilization, will we not be excited once we find that there are planets suitable for human survival in the galaxies near the solar system? I believe it will be wonderful, and interstellar migration is also necessary.

Of course, these are just some guesses of scientists. At present, human beings have not really discovered alien civilization, and even the most basic extraterrestrial life has not been discovered. However, scientists are still trying to find alien civilizations. In the next few decades, with the use of more advanced detection equipment, it may be possible to find alien civilizations. However, it is hard to say whether it is an opportunity or a danger for human beings at that time.

Little friends, what do you think of this? Welcome everyone to leave a message below to discuss and express their views and opinions.