What would happen to humanity if the sun went out?

What will happen to the Earth after the sun goes out?

Many people will definitely answer that after the sun goes out, the earth will fall into darkness and life will face the greatest extinction. Is this really the case?

We all know that if we put a cup of 100℃ water into the freezer, it will not cool to 0℃ as soon as it enters, but will cool down slowly.

Similarly, the sun going out does not mean that its energy disappears out of thin air.

Perhaps it will be 10,000 years later before humans truly realize that the sun is going out.

Next, let’s take a look at what changes will happen to the earth after the sun goes out.

The sun goes out

There are two ways for us to perceive the sun. The first is vision, which is to see the sun directly, and the second is touch, which is to feel the heat emitted by the sun.

The distance between the sun and the earth is about 150 million kilometers. The light from the sun takes 8 minutes to reach the earth. Therefore, many people believe that after the sun goes out, humans will lose their light in 8 minutes.

So is the sun's extinction really as simple as just not shining?

As early as 1920, British astronomer Eddington believed that the energy of stars comes from nuclear fusion reactions, and our sun is the largest nuclear power plant and nuclear reactor.

The light we see comes from the energy displayed by nuclear fusion in the sun.

The so-called extinction of the sun actually means that the sun's nuclear fusion has stopped. However, when the nuclear reaction stops, its energy will not disappear immediately. Therefore, the extinction of the sun does not mean the cooling of the sun.

That is to say, even if the sun's nuclear fusion reaction stops, the sun will still be a blazing fireball, radiating heat outward.

Every second, about 600 million tons of hydrogen atoms participate in nuclear fusion reactions, and the energy received by the Earth is only one 2.2 billionth of the total energy of the sun.

The light of the sun comes from the radiation produced by nuclear fusion energy. We all know that radiation exists for a long time and it will not disappear just because the nuclear reaction stops.

After the sun goes out, the radiation will not dissipate and the sun will continue to shine.

Physicists have calculated that the energy generated by 600 million tons of hydrogen participating in nuclear fusion will take about 10,000 years to dissipate.

After the sun stops its nuclear fusion reaction, the energy generated in the last second can continue to radiate for 10,000 years.

Therefore, it will take humans not 8 minutes but 10,000 years to feel the sun going out.

What will happen to the earth at this time?

What will the Earth become?

David Stevenson, a professor of planetary research at California Institute of Technology, said that the current average surface temperature of the Earth is about 18°C, and this temperature will drop when the sun cools down completely.

In a week it will drop to minus 18 degrees Celsius, in a year it will drop to minus 73 degrees Celsius, and one million years later, the temperature of the earth will be minus 240 degrees Celsius.

This temperature is close to that of the surface of Pluto, which means that after the sun really goes out, the earth will become another Pluto.

Will life on Earth still exist then?

The answer is yes. Life is afraid of heat but not cold, because high temperature will cause irreversible damage to organic matter. Being a frozen planet is better for life than being a hot planet.

Because the earth has a hot "heart", that is the core.

Professor Stevenson believes that the surface of the earth will be covered by a thick layer of ice, but under the ice sheet, there will still be a liquid ocean because the earth has not cooled down yet.

From the inside to the outside, the earth is divided into the core, mantle, and crust, and the ocean is part of the crust.

There is energy transfer between these three parts, and the temperature of the core is the highest, between 4000 and 6000℃.

The mantle is divided into the upper mantle and the lower mantle. In the upper mantle close to the crust, there is a asthenosphere with a thickness of more than 100 kilometers and its temperature is between 700 and 1400℃.

The asthenosphere is what we call the birthplace of magma, which enters the earth's crust in the form of volcanic eruptions.

The Earth has experienced several major ice ages in its history. The longest one can be traced back to the Huronian Glaciation about 2.4 billion years ago, which lasted for 300 million years.

This freezing catastrophe did not end life. Instead, after this ice age, the ability to breathe aerobicly evolved.

This is because the Earth's interior is constantly active, and the energy they generate flows from the inside out, keeping the water on Earth liquid.

There are also hot springs on the seabed, and the temperature near them can reach a level suitable for life activities.

After the sun goes out, the temperature of the earth will drop sharply, and some gases and water vapor in the atmosphere will form an ice sheet that covers the earth.

However, the earth's oceans will not freeze completely. Deep in the ocean, there are still underwater hydrothermal vents, and life will gather here to continue to reproduce.

However, advanced life forms like humans may disappear completely.

To be precise, the Earth did not become Pluto, it became something like Europa.

The way to save

It will take about 10,000 years for humans to perceive the sun after it goes out, but it can be detected after the nuclear reaction stops.

Therefore, humans have 10,000 years to respond.

Although the sun is the heaviest celestial body in the entire solar system, its largest content is actually hydrogen atoms, which have the smallest mass. The sun's energy comes from the nuclear fusion reaction of hydrogen atoms.

Humans can also carry out this reaction on Earth by bombarding hydrogen atoms with neutrons to trigger a hydrogen nuclear fusion chain reaction.

If humans want to reignite the sun, they can fire a large number of neutrons at the sun to restart the nuclear fusion reaction.

Perhaps humans can also develop controlled nuclear fusion on Earth, which is also called "artificial sun."

The essence of an artificial sun is a nuclear fusion reactor, but its reaction speed and energy generation can be artificially controlled, and energy conversion can be achieved.

If humans master this technology, even if the sun cools down completely, humans will not have to worry about the earth being frozen into an ice ball.

Eric Blackman, an astronomy professor at the University of Rochester, said that the extinction of the sun may not cause the extinction of mankind because the energy of the earth is beyond our imagination.

Human beings always say that we are in an energy crisis. That’s because the energy we use is still limited to the earth’s crust. Human beings are currently unable to use the energy in the mantle and core.

Blackman believes that just one volcano would be enough for human development for hundreds of years, and that using geothermal energy like Iceland can sustain cities during the polar night.

Professor Blackman also believes that it is unlikely that the sun will suddenly go out, and its future extinction will probably have to wait until the day the sun dies.

Life of the Sun

The sun is a G-type star in the universe, commonly known as a yellow dwarf. The lifespan of this type of star is usually around 10 billion years. The sun has already gone through about 4.6 billion years, which is less than half.

According to the general evolution path of yellow dwarf stars, the Sun will expand and become a red giant in 5 billion years.

During the red giant period, the Sun will successively engulf Mercury, Venus, Earth, and Mars, and the final boundary will be close to the orbit of Jupiter.

When the expansion approaches its limit, the red giant collapses and most of the external matter is thrown into the universe, forming a nebula.

The inner core is preserved, emitting a cool white glow; this is a white dwarf.

At this point, the sun has completed its life, and the solar system has basically collapsed. The four rocky planets were swallowed up during the red giant period and have long since become part of the nebula. The remaining four gas planets will lose their original gravity and eventually dissipate, also becoming a nebula.

At the same time, the nebula formed after the collapse of the sun will begin to form new stars at a certain period of time, starting a new journey.

Faced with such extinction, humans have no way to completely preserve themselves, because the Earth will be "eaten" by the late-stage expanding sun. The only thing humans can do is to leave the solar system.

However, 5 billion years is too far away for us, and it is even a question whether humans can survive until that day.

If there were still humans at that time, our civilization level would have already broken through the limits and become one of the most advanced civilizations in the universe, and perhaps we would have already left the solar system.

For individual creatures on Earth, the possibility of witnessing the sun going out with their own eyes is almost zero.

Source: Cosmic Decoding