If the sun suddenly disappears

What would happen to the Earth if the sun suddenly disappeared? The answer is, of course, the Earth will undergo great changes, but at the moment of the disappearance of the sun, the Earth will not immediately change, because the speed of propagation of the sun's light and gravity is the speed of light, about 300,000 kilometers per second, and the average distance between the Earth and the sun is about 150 million kilometers, so in about 500 seconds, the Earth's great changes will begin, and from then on the prelude to the difficult survival of mankind.

After the sun disappears for 500 seconds, the earth's giant change will start with the sudden darkening of the sky on the sunny side of the earth, losing the sun's light and heat, the earth's surface will start to cool down, and because the higher the temperature of the object, the stronger its ability to radiate heat, so at the beginning, the earth's cooling speed is relatively fast, and with time, the earth's cooling speed will gradually tend to slow down.

It only takes 24 hours for the average surface temperature to drop to about 9 degrees Celsius, 1 week later, to about -17 degrees Celsius, 1 month later, to about -40 degrees Celsius, at this time on the surface of the Earth, in addition to a very few geological structure rupture can rely on the Earth's internal heat to maintain the existence of liquid water, the other areas are all frozen, the Earth gradually becomes a frozen The Earth gradually became a frozen planet.

In this month's time, the earth's ecosystem will completely collapse, a large number of species will become extinct, and human beings will also suffer a severe blow, in the endless darkness and ice, the infrastructure built by human beings failed in large numbers, various resources are increasingly scarce, the number of human beings will therefore be sharply reduced, while the surviving human beings have known that the sun will not rise again, they will consciously to nuclear power plants or The surviving human beings already know that the sun will not rise again, and they will consciously gather in nuclear power plants or areas rich in geothermal energy.

On the other hand, after the loss of the sun's gravity, the original orderly solar system will become chaotic, and all kinds of celestial bodies will be out of their original orbits, in this case, the probability of collision between the earth and other celestial bodies will be greatly increased, once a large-scale celestial collision, not to mention human beings, even the earth itself may be destroyed.

Assuming that the Earth is lucky enough to escape a devastating celestial impact, the average surface temperature will drop to minus 70 to 80 degrees Celsius after 1 year. 1 year after the disappearance of the Sun, the Earth's atmosphere is already very stable, and all regions of the Earth's surface will cool down simultaneously, at which time the surface of the Earth will hardly see any signs of life, and the number of human beings is reduced to the tens of millions, which is because the human Many settlements are no longer able to support human survival.

The surviving humans live in a few large underground bunkers, and their energy comes from geothermal and nuclear energy as well as traditional fossil fuels. There is not much food left at this point, but humans have begun to experiment with artificial light sources to cultivate plants, and have made some progress.

It is worth noting that 21% of the Earth's atmosphere is oxygen, with a total mass of up to 1.882 x 10^18 kg, so the source of oxygen is not a problem, but at this time there is no more carbon dioxide in the Earth's atmosphere because when the temperature is below -56.6 degrees Celsius, carbon dioxide freezes into a solid state and scatters above the surface, so when cultivating plants, if there is not enough carbon dioxide (humans can produce it themselves), humans need to collect it on the surface of the earth.

After 20 years, the surface temperature has dropped to about minus 220 degrees Celsius, at which temperature the Earth's atmosphere no longer exists, because oxygen and nitrogen have frozen solid. If humans on Earth still exist, then they have mastered the technology of artificially cultivating plants, and they may even cultivate some mollusks as a source of protein, and as for the resupply of oxygen, they can just go digging on the ground.

At this time, humans have been stabilized on Earth, but are facing an increasingly serious problem: they can collect fossil fuels and nuclear fuel for nuclear fission is ultimately limited, and geothermal energy is not enough to support their survival needs. So mankind will at this time devote itself to the development of controlled fusion.

Before fossil and nuclear fuels are exhausted, if mankind does not master controlled fusion, mankind will not escape the fate of extinction, and if mankind does succeed, mankind's struggle for survival will end and the earth will usher in a new era.

Just the deuterium in the Earth's oceans, the energy released through nuclear fusion can support modern humans for billions of years, so it is not difficult to imagine that humans will then have a constant source of powerful energy, I believe that within a hundred years, they can return to the surface of the Earth to live, and bring the long-lost light and warmth to the Earth.

It is a pity that for a long time, mankind did not have the goal of space exploration, because after the sudden disappearance of the sun, many celestial bodies in the solar system "scattered", into the vast space of the universe, only a dark moon is still accompanying the Earth.

Only after a long time, the Earth "wandering" in the cosmic space into (or close to) another star system, or mankind has developed the technology can be interstellar navigation, mankind can further development in the universe.

Of course, the above can only exist in our imagination, after all, from the known laws of the universe, the sun is impossible to disappear somehow.