In the future, mankind must leave the earth, a planet 4.2 light years away, or become a new home for mankind.

The earth is not only the home of human beings, but also the home of tens of millions of species on the earth. Its perfect environment has evolved into a paradise for the development and progress of human civilization.

However, one day in the future, mankind will eventually leave the earth to find a new home. Although this day is still quite far away, we must make preparations in advance.

The environment of the earth will not always be suitable for human habitation. The sun that gives life to the earth will swell into a red giant one day in the distant future because of the exhaustion of fuel. By then, the earth will be completely burned, the ocean will be completely evaporated, and the earth will be dead.

Even if we don't need to think about the distant future at present, we need to always be alert to cosmic events that may bring fatal disasters to human civilization. It must be said that asteroid impacts and super-strong gamma-ray bursts may completely end human civilization.

As Hawking said before his death: Humans can't put all their eggs in the same basket. The implication is that human beings should be not only the civilization of the earth, but also the civilization of the universe. We need to spread human civilization to a broader cosmic civilization, so as to better continue human civilization.

Adhering to this belief, astronomers have been trying to explore and discover livable planets in recent decades. It is exciting that there is such a livable planet not far from the solar system, which is likely to become the first stop of human interstellar travel in the future.

It is proxima centauri, about 4.2 light years away from the Earth. Proxima centauri belongs to a star in the triple galaxy. Its volume is very small, only about one seventh of the diameter of the sun. It is a red dwarf star with low brightness relative to the sun.

So how did astronomers discover proxima centauri?

What we usually call "the planets revolve around the stars" is actually not rigorous. It is more accurate to say that planetary stars rotate around the center of mass of the system. Stars are not stationary, and they will swing slightly, but because the mass of stars is very large relative to planets, all such swings are not obvious.

It was by observing this tiny wobble that astronomers discovered the existence of proxima centauri. At the same time, a planet orbiting proxima centauri was discovered and named proxima B. Analysis shows that it is similar to the earth and is also made of rocks. The time around proxima centauri is very short, only about 1 1 day.

This shows that the neighboring star B is very close to the star (proxima centauri), but we don't have to worry about being burnt at such a close distance, because proxima centauri is a red dwarf, and its temperature is much lower than that of the sun. Proxima B, like the Earth, is located in the livable zone of proxima centauri Centauri star system, and may even have an atmosphere.

If so, proxima centauri is even more perfect than the Earth, because red dwarfs have very small mass and long life. The life span of our sun is about 65.438+00 billion years, and the current age of the sun is 5 billion years.

The life span of red dwarfs can reach 1000 billion years or even longer, which means that the planetary system of red dwarfs can exist stably for a longer time. Imagine that if humans really migrate to proxima b in the future, we still have hundreds of billions of years to continue to develop human civilization.

No wonder scientists say that red dwarfs are the ultimate destination of human civilization.

Proxima centauri Centauri system is the closest star system to the sun, only 4.2 light years away. However, for today's human science and technology, even if it is only 4.2 light years, it is too far away. Voyager 1 has been flying for more than 40 years, and this time it has flown more than 20 billion kilometers. At this rate, it will take 70,000 years to fly to proxima centauri. If you want to fly to proxima centauri, the speed of human beings must reach at least sub-light speed!