At present, only 4 17 1 exoplanet and 3092 star systems have been confirmed. If the universe is an ocean, then mankind has not even found a drop of water in it, let alone looking for life in the ocean.
For the earth living independently for a long time, whether there is other life in the universe is a problem that needs careful consideration. After all, human beings have been in space for 59 years, and no signs of extraterrestrial life have been found.
Alien life needs to be witnessed to believe? Big data shows that if there is only life on earth in the universe, it is a miracle among miracles.
According to the observation data of Kepler mission, there are about 400 billion stars in the Milky Way. Although most stars are not suitable for planets to produce life, only about 7% of them are very similar to the sun, with about 28 billion stars (excluding red dwarfs, only yellow dwarfs).
According to Kepler's big data calculation, 1 yellow dwarf will form a star system suitable for life in every five yellow dwarfs similar to the sun. Calculated by 28 billion yellow dwarfs, there are about 5.6 billion star systems suitable for survival in the Milky Way, which is a huge number. However, in the Milky Way, 5.6 billion star systems are at least several billion light-years apart.
In this way, there may be a lot of civilizations in the Milky Way, but why haven't humans found them?
The main reason is that astronomical observation technology is still underdeveloped. The closest exoplanet to the Earth is also 1 1 light-year. Through such a long distance, scientists can only judge the structural composition and atmospheric composition of the planet slightly according to the spectrum, and can't judge whether there is life on the exoplanet. What's more, humans have only discovered more than 4,000 exoplanets.
Alien life may exist, but as long as you can't see them, you are denied.
Is alien life worth fearing? On the day when alien life really appears, if the level of science and technology is higher than that of the earth, will it rob the earth of its resources?
On the day when humans discover alien life, will humans invade aliens if the technology of the other side is underdeveloped?
Life is not a saint. When the lives of two different planets meet, they will get along well if the gap is not big, and conflicts will easily occur if the gap is big. Alien life is not a wonderful journey of exploration, but a journey full of danger at all times, just like exploring in the deep sea, where you may meet beautiful fish or sharks.
Whether there is other life in the universe, no matter what the answer is, human beings should feel fear and be prepared for danger in times of peace.
Man, galaxy and universe: as a life in the universe, man is nothing compared with life in the universe, but it should be noted that man was born very early-if the universe is a human life, then the present universe has not really been born.
Many astronomers believe that life on earth may be the first advanced civilization in the universe, and other life may not have appeared yet. If this conjecture is correct, then the earth may shoulder the heavy responsibility of managing the universe. The imaginary advanced life may be the future human beings. However, with the study of the Milky Way by astronomers, the possibility that human beings are the first life began to decrease, because the most "prosperous" period of the Milky Way was about 654.38 billion years ago.
At present, most of the stars in the Milky Way are not young, many of them are old or dead, and few stars are suitable for life. But 65.438 billion years ago, the stars in the Milky Way were younger and more suitable for life. The earth may have missed the "golden age" of the Milky Way. Today, the vast majority of life in the galaxy has long since left, leaving only the life of lower civilization.
Why did life leave the galaxy? The reason is very simple, because two billion years later, the Milky Way will collide with the Large Magellanic Cloud, and advanced life capable of interstellar communication and interstellar travel will definitely leave the Milky Way ahead of time to live on a safer planet. Life left in the galaxy must develop to a sufficient level of science and technology before the day of destruction, or it will be extinct.
In order to keep life going, it may be the best way to find other civilizations in the same galaxy. Astronomers have identified 36 places where life is most likely to exist by exploring the radio signals of the Milky Way. Scientists believe that civilizations that can use radio should be closer to the civilization of the earth, so it is easier to help each other.
Summary: With the understanding of the scale of the universe, the possibility of other life in the universe is increasing.
Humans have not found other life, mainly due to the limitation of scientific and technological level. On the contrary, we should think more about why alien life won't contact us.
Perhaps it is because the Milky Way has long been abandoned by other life, because the time of the Milky Way is running out; Perhaps it is because there is no means of interstellar communication in the universe; Maybe human beings are really the first life in the universe. ......
However, in any case, seeing is believing is always the truth. As long as humans don't see alien life with their own eyes, this debate will not stop.