If you had the chance, would you be willing to leave Earth and travel to other planets in the universe?
Among the more than 5,000 exoplanets discovered so far, astronomers have screened out a number of second Earths, among which the highest similarity is K2-18b, which is eight times the size of the Earth, 124 light years away, the parent star is a red dwarf, the orbital period is 33 days, at first glance it seems a little too close to the star, but because the heat of the red dwarf is not as good as that of the yellow dwarf star like the sun, K2-18b is still generally located in the stellar habitable zone.
In 2019, scientists at the University of London discovered water vapor on K2-18b for the first time, which means that it contains at least hydrogen and helium, and even has methane and nitrogen in the atmosphere, which provides conditions for the birth of life, and even if there is nothing on it, it is also a planet that can be inhabited by humans by the presence of water vapor alone.
The only thing that needs to be overcome is its gravity environment, but fortunately, K2-18b is not the only extra-habitable planet, Kepler-452b is also a super-Earth, 1400 light-years away, it is 5 times the mass of the Earth, and the orbital period is 385 days, which is basically the same as our Earth, but its star Kepler 452 is older than our Sun and brighter than the Sun, so Kepler-452B may have a very strong greenhouse effect and is not very suitable for direct occupancy.
In addition to these extrasolar worlds, astronomers believe that the Moon and Mars will also become the new home of human civilization in the future, more precisely, with the continuous rise of the earth's population and the development of outer space resources, it is a sure fact that human civilization as a whole will enter the space age, and the difference is only sooner or later.
The key technology is not Musk's recyclable rocket, but the space elevator technology brought by the breakthrough in material technology, only it can allow a large number of people and materials to enter space at a very low cost, and finally establish an industrial system in space, launch spacecraft from space to the moon and Mars, and maximize efficiency.
At that time, the first batch of ordinary people who will go to the moon and Mars in the real sense will become the focus, because compared with the previous scientific research and experiments, the main force in the era of space development can only be ordinary people who have undergone short-term training, so that space and other planets can become a real new home for mankind, rather than a scientific research base.
With the current technology, it takes about a week to go to the moon and half a year to Mars, and this time may be shortened by half in the future, so that the moon can rely on the supply of the earth to maintain its operation for a long time, but the development of Mars can only rely on the self-sufficiency of the first few Martian developers, and finally make Mars a new world that can operate without relying on the resources of the earth.
This pattern, similar to the relationship between the New World of America and Europe, is very likely to lead to contradictions between Martian humans and Earth humans in the future, and even the entire human civilization will become a smaller civilization due to the increasing distance in space.
In many science fiction works, in fact, there is a trend of human civilization in the future of fragmentation, such as the famous Asimov's "Galactic Empire" series, the human civilization all over the galaxy eventually collapsed into several smaller civilizations, which is essentially because the speed of information transmission cannot exceed the speed of light, resulting in the inability of several settlements to communicate in time, so this ending is essentially unavoidable.