With the rapid development of science and technology, human beings have realized the infinity of the universe. For the universe, human beings have been looking for opportunities to explore. People don't know how big the universe is, and people in ancient times have also thought about it, but until now no one can answer this, and no one knows where the end of the universe is.

When people see the sea, people will sigh, the sea is too big! And the earth we live in is only a very small existence in the universe. What we know is only the various planetary groups closest to us, which is what we call the solar system. Although we think the earth is big enough, in the solar system, the earth is only a very small planet.

Hundreds of years ago, after continuous efforts and development, human civilization finally entered the road of scientific and technological development. With the help of science and technology, human beings quickly realized the dream of flying, and went out of the earth to start exploring the universe. When we walk out of the earth and see the vast universe, people will think of the same question: Does alien intelligent life exist? Maybe in the years when humans just walked out of the earth, many people still had a little doubt about the existence of alien civilizations. However, with the continuous development of human science and technology and the continuous improvement of our understanding of the universe, more and more people continue to affirm that alien civilizations exist, including many cosmologists.

More than half a century has passed since humans began to explore the world. But unfortunately, we have not found any signs of other creatures living in outer space. It seems that in this huge universe, only human beings inherit it alone. But because the universe is too big for humans to predict, it is impossible for us to claim that we are the only living beings in countless universes.

But since alien civilizations exist, why can't we find them? According to relevant data, it is not impossible for humans to discover alien civilizations. But these civilizations have undergone tremendous changes in the planets that gave birth to life over a long period of time, so the life forms on them are likely to have died out. Simply put, it's not that they don't exist, they're gone.

Scientists predict that the existence of life in the universe may be a common phenomenon, and even the solar system may have a lot of extraterrestrial life. It's just that the probability that the living planet wants to evolve into a civilized planet like Earth is very low. To know the evolution of primitive life to intelligent life, it takes billions of long years. In such a long time, as long as there is a huge catastrophic destruction event on this planet, it is possible to end the evolutionary process of life.

Through analysis of existing observational data and theoretical deductions, scientists estimate that there are about 10 billion habitable planets in our galaxy alone. We can see that this is a very large number, and we can easily infer that a lot of life must have been born in these habitable planets.

For example, Mars, the neighbor of the earth, through a large number of observations, scientists believe that Mars was also a beautiful planet of life in the early days, and it may have been born at the same time as the early life of the earth. It’s just that a huge disaster happened on Mars later, which led to the end of life on it, while life on Earth continued to evolve, and finally human beings were born. It can be seen that there may be too many life planets in the universe to estimate, but there are not too many civilization planets like the earth. It is also very difficult for humans to find alien civilizations, unless we have the ability to travel between stars and can quickly reach various galaxies for exploration.