The sun has been burning for 4.6 billion years. What will be the fate of the earth when it burns out in the future?

As a star, the Sun has its own lifespan, a fact that many people understand. Our sun has been "burning" for almost 4.5 billion years since its birth. During these 4.5 billion years, it has been squandering a large amount of hydrogen inside it every minute and every second. These hydrogen atoms are under great pressure and pressure inside the sun. It was pressed into helium at extremely high temperatures. In the process, part of the mass was converted into energy and emitted, bringing light and heat to the earth and the entire solar system.

(Beautiful sunrise)

At present, hydrogen inside the solar photosphere accounts for 74.9% of the total mass, and helium accounts for 23.8%. Although every 600 million tons of hydrogen are converted every second, but so far it looks like the sun still has plenty of fuel. According to scientists' calculations, it will take more than 7 billion years for the sun to burn out all the hydrogen inside it, so it seems to be very early.

You might say that before the sun completely burned out its hydrogen, it had already turned into a terrible red giant. The diameter of this red giant was more than 100 times larger than the current sun. 250 times. By that time, the sun will have engulfed the earth entirely. Even Mars will not be spared, let alone humans on the earth!

(The red giant star will engulf the earth and even the orbit of Mars)

Indeed, according to scientific calculations, the sun in its later years will expand rapidly to 200 to 250 times its current diameter. Based on this ratio , the earth will indeed be swallowed by the sun. I also posted a picture like this to scare everyone:

(The sun’s red giant engulfs the earth)

However, the truth may not be so scary, because the sun that becomes a red giant has many Chances are it's not that scary, it's probably something like the photo below. This is a photo of the red giant "Mira A" 400 light years away from the earth. It is not at all like the spherical shape of a standard red giant in our impression. Because the star's mass is limited, when it expands to hundreds of times its normal diameter At that time, its outermost atmosphere was extremely thin and no longer had a distinct photosphere. Except for the bright and hot core, most of its photosphere had turned into a corona or even resembled a nebula.

(Red giant star "Mira") Although it will not be swallowed up quickly, the earth will still face the fate of being scorched while traveling through such thin hot gas. It would be better if it was farther away from the sun.

If the earth does not have the planetary engine of "Wandering Planet", how can it be further away from the sun? We know that the gravitational pull between stars depends on their mutual masses. The sun converts 4 million tons of mass into energy every second and throws it into space. In 5 billion years, the mass of the sun will be reduced to about 80% of the present. In other words, in the next 5 billion years, the sun will have a negative impact on the planets. The gravitational pull of the Earth is getting smaller and smaller, and as the solar wind continues to push outwards for billions of years, the Earth will become farther and farther away from the Sun. Whether it can eventually climb to the orbit of Mars or even Jupiter and escape the fate of being burned, this requires The conclusion can be drawn only after calculation.

(Planetary Engine) The bad news is that mankind may not wait until the day when the sun turns into a red giant, and it will face disaster.

The sun is getting brighter and hotter. This trend started from the birth of the sun and will continue. Scientists believe that in another billion years, due to changes in the temperature of the sun, Due to the irreversible greenhouse effect of the earth, the oceans will evaporate, the land will turn into desert, and it will be difficult for life to survive on the earth.

Therefore, human beings will not wait until the imminent day to find a way out. Perhaps in tens of millions of years, our descendants will find a way to move to another planet and go to a better place to build a new planet. 's home.

Do you think such a beautiful idea will become a reality? Welcome to leave a message in the comment area. For the earth, the sun is very important, and all life on the earth is related to the sun.

Plants need sunlight, and animals feed on plants or other animals, and also rely on the oxygen produced by photosynthesis of plants to survive. Their energy sources ultimately point to the sun. Sunlight hitting seas and lakes causes water to evaporate into the atmosphere and move around the world, bringing precipitation to life on Earth. The sun also heats the atmosphere, creating winds and seasons.

It can be said that without the sun, there would be no colorful life on the earth. According to the theory of star formation and evolution, it is speculated that the burning of stars will last for about ten billion years. The sun has been burning for 4.6 billion years and will burn for more than 5 billion years. When it burns out in the future, what will be the fate of the earth?

1. The distance between the sun and the earth is 150 million kilometers. The last light from the sun reaches the earth 8.3 minutes later.

The earth will lose light and heat at this time, and the dayside of the earth will be completely dark.

2. At the same time, the sun’s gravitational pull on the earth disappears.

The earth will fly out along the tangent direction of its original orbit at a speed of about 30km/s, and the "wandering earth" will become a reality.

3. All planets and small celestial bodies in the solar system will also be in chaos.

As the earth travels through these randomly flying small celestial bodies, it may collide with an asteroid with a diameter of tens of kilometers or with Jupiter. It all depends on the luck of the earth.

4. Due to the lack of solar radiation, the earth will be completely in the universe with a temperature of -270 degrees below zero.

The surface temperature drops sharply, a process that takes less than a hundred days.

5. As the temperature drops, the clouds in the sky will disappear and carbon dioxide will liquefy.

As the main greenhouse gas on the earth, once carbon dioxide is liquefied, ground facilities will be completely destroyed and covered with ice.

6. All oceans will freeze, with a thickness of more than a thousand meters, and the creatures living on the seabed will gradually become extinct.

Only microorganisms that live on the seafloor, relying on geothermal energy to survive, may survive. The entire earth, except for the depths of the oceans, will be frozen.

7. If the earth loses the stabilizing effect of the sun on the magnetic field, humans and animals will also lose their way.

8. The animals and plants on the earth will basically become extinct.

Animals will either freeze to death or starve to death, and plants will dry up if they lose photosynthesis.

The sun is in its prime and is a typical yellow dwarf star. The lifespan of a yellow dwarf is about 10 billion years. Our sun is now about 5 billion years old. In theory, it still has a lifespan of 5 billion years. Eventually, the sun will go through the red giant era and eventually become a white dwarf. The Terrifying Helium Flash

Liu's "The Wandering Earth" is not just a figment of imagination, it is also based on science. Generally, low-mass stars will frequently undergo helium flashes after entering the red giant era, releasing a large amount of energy in just a few minutes, and the earth will be instantly vaporized in the orbit of the earth. Stars are mainly composed of hydrogen and helium. Under the collapse of their own gravity, the core of the star is in a state of high temperature and high pressure. Hydrogen will undergo a nuclear fusion reaction and eventually turn into helium.

In this way, the star will reach a dynamic equilibrium process, and eventually all the internal hydrogen will be converted into helium. The helium in the core will react violently under its own pressure and eventually release huge energy outwards. This is also what is mentioned in "Wandering" The reason why humans want to take the earth to escape from the solar system in "Earth". Red Giant Era

When the sun enters the red giant era, it will expand rapidly, and eventually the edge of the sun will reach the orbit of Mars. This means that all four terrestrial planets in the solar system will be swallowed by the sun, but as time goes by, Toward the periphery, the gas density becomes lower.

In other words, the earth will move in the hot expanding gas inside the sun, and all living things on the earth will inevitably become extinct. The earth's speed continues to decrease, and it will eventually plunge into the core of the sun.

Scientists predict that the sun still has a lifespan of 5 billion years, which means that the sun is now in "middle age", and we humans have caught up with a good time!

However, even a celestial body as huge as the sun will one day die due to exhaustion of fuel! After 3.5 billion years, the sun gradually began to evolve into a red giant, its fuel gradually ran out, and its volume began to expand!

Mercury and Venus, which are closer to the sun, will be swallowed up by the sun. Our earth may be able to avoid being swallowed up, but even if it is not swallowed up, only a completely dead "body" will be left, because as the sun As the sun expands, the temperature of the earth will rise sharply, all the water on the earth will evaporate, and the atmosphere will be driven away into interstellar space due to the approach of the sun!

Therefore, when the sun runs out of fuel, there is only one way left for the earth, and that is: death!

Since the earth will also die, what will the humans living on the earth do then?

It seems too early to discuss this issue now, and even a bit unfounded. The premise is that we need to be qualified to discuss this issue, which means that humans are lucky enough to continue civilization until 5 billion years later!

But if human civilization can really continue beyond 5 billion years, do we still need to worry about mankind? Humans must have already left the earth, the solar system, and even the galaxy!

So, don’t think about what will happen in 5 billion years. It’s better to remove the word “100 million” and think more about what will happen in 50 years! Compared with the fate of the earth, we are actually more concerned about the fate of mankind.

Some people may say, isn’t this the same? Now, it is indeed the same, because for the current human beings, the earth is our home for survival. We are still infants and cannot do without the embrace of the earth.

The sun has been burning for about 5 billion years, and it can continue to burn for about 5 billion years... What a coincidence... If human civilization can survive, it will inevitably break away from the earth. Holding my arms, running towards the vast space, as for where to go, how do I know...

In fact, human beings will have to leave the earth in less than 5 billion years, because with the evolution of the sun, the earth is slowly The reason for the slow departure from the habitable zone is not that the earth's orbit has drifted, but that the sun's radiation is becoming more and more intense.

We all know that the sun releases energy through the fusion of hydrogen nuclei near the core into helium. In the main sequence star stage of the sun, it will be in a state of equilibrium - the fusion of hydrogen nuclei produces The thermal expansion just resists the gravitational contraction. However, as hydrogen nuclear fusion continues, more and more helium will accumulate near the core, and the core will become heavier and heavier. This will cause the sun to need to use more violent hydrogen nuclear fusion to generate higher-temperature thermal expansion to resist gravity. collapse.

More intense hydrogen nuclear fusion causes the sun's temperature to become higher. Therefore, the surface temperature and luminosity of the sun increase year by year as the core helium increases. According to scientists According to calculations, the temperature rise caused by the sun's radiation will cause the surface temperature to rise to 100 in about 1.5 billion years, which means it will exceed the boiling point of water at sea level, and all water on the ground will evaporate!

In fact, in the long years before, the earth has been unsuitable for human survival...

Fortunately, humans still have hundreds of millions of years to prepare. Transforming Mars will be a civilization The first step of expansion is the satellites of Jupiter, and then the satellites of Saturn. There is no shortage of planets in the solar system that humans can immigrate to, but this is not a long-term solution after all. Our journey is to the stars and the sea! With hundreds of millions of years of continuation and development, we really can’t imagine how far human civilization can reach. By then, the sun will no longer be a necessity. If humans are more sentimental in the future, they can push the earth away from the current orbit and keep it in the habitable zone. It would not be difficult to push it to other star systems, right? At that time, would they still remember that there was a science fiction writer named Liu Cixin on the ancient earth who once wrote a science fiction novel called "The Wandering Earth"? ?

If they knew it, they would think it would be too low to push away the earth, so they finally decided to push the sun away and replace it with a younger star. Well, there is nothing wrong with it. #thisisveryscientific#

To tell the answer directly: The fate of the earth will not be swallowed up, but it will be dried out, and there is no need to wait for the sun to burn out. In about 1.9 billion years, the earth’s atmosphere and water will be Dried by the sun.

Let’s briefly talk about the life process and final destination of the sun: Some say the sun is 4.6 billion years old, some say 5 billion years, but they all agree that the sun’s lifespan can reach about 10 billion years. This means that the sun will die in about 5 billion years. Among them, the fusion of hydrogen into helium can last another 4 billion years. After the hydrogen is exhausted, the interior of the sun temporarily stops nuclear fusion and loses the ability to resist its own huge gravity. The core will shrink and the temperature will rise, but the outer layer of the sun will It will expand, the surface temperature of the sun will drop, and it will become a red giant.

When the core temperature rises to 100 million degrees, helium will be ignited, and then fused to produce carbon, thus entering an asymptotic branch giant. This burning time will last about 1 billion years. When all the helium elements in the sun are converted into carbon, the sun will throw off its outer shell and form a planetary nebula.

At the same time, the core will collapse and eventually form an Earth-sized white dwarf with a density of up to 10 tons per cubic centimeter. The sun is of medium mass and cannot explode as a supernova to form a neutron star or a black hole. It can only form a white dwarf star, which is the final destination of the sun.

From the above description, we can know that the sun can burn for about 5 billion years, but what is the fate of the earth during these 5 billion years? Does it only depend on when the sun burns out? Let’s talk about it below. In fact, in addition to the final destruction of the sun that will definitely have an impact on the earth (assuming that the earth can exist in 5 billion years), there are two other points in time that are very detrimental to the earth. The first point in time - 4 billion years later

is when the hydrogen element in the sun is completely burned out. At that time, the sun's outer shell will expand and become a red giant, and the sun's radius will expand to 2.42 astronomical Unit (1 astronomical unit = 149 million kilometers, which is the average distance between the sun and the earth), which means that the sun will expand beyond the current orbit of the earth. If the earth was still there at that time, the sun would engulf the earth. As for Mercury, which is closer to the sun And Venus, not to mention that. Of course, at that time, the sun will lose about 30% of its mass due to consumption and stellar wind, and the planetary orbits can be extrapolated, and the earth may survive. But according to the latest research, even if the earth is not swallowed on the spot, it will eventually be swallowed by the sun due to tidal effects because it is very close to the sun. The second time point - 1.9 billion years later

According to the latest research, the surface temperature of the sun is also slowly rising when it is still in the main sequence (the hydrogen element is far from exhausted). It is getting brighter and hotter. If this trend continues, the earth's water and atmosphere will all evaporate in 1.9 billion years.

Although the earth exists, humans will not be able to survive and all living things will become extinct.

Without humans, the earth would have no destiny. The fate of the earth no longer matters.

It can be seen from the above that the fate of the earth has undergone amazing changes without waiting for the sun to burn out. Therefore, human beings should be prepared for danger in times of peace and prepare early, but we should not be unfounded. After all, there is still time. As long as we make preparations calmly, we will change the destiny of the earth, which means changing the destiny of mankind. If you want to change the fate of the earth, you can first change the sun. By then, humans may have reached the Kardashev Index Il civilization and be able to utilize the energy of the entire solar system. It is not a big problem to transform the sun. In this way, the fate of our earth will be It also changed. Of course, maybe humans will no longer live on the earth at that time.

Due to the limited mass of the sun, when the sun's nuclear fusion is completely completed, it will collapse into a white dwarf star. However, before becoming a white dwarf, the sun will become a red giant in 5 billion years.

The diameter of this red giant is 200 million kilometers. The surface temperature of the red giant is up to 2000 degrees, and the material is very thin. Although the Earth's orbit becomes larger due to the reduced mass of the Sun, the red giant is likely to swallow the Earth into this red giant, which will be the end of the Earth.

In fact, before this, the heat of the sun has evaporated all the water on the earth, and the solar wind will blow away all the materials with lower melting points on the earth, including the atmosphere. The earth becomes a red-hot "stone ball".

At that time, all living things on the earth had already become extinct. As for humans, we don’t have to worry about them. Human beings at that time had already become extinct on the earth. As for whether it can fly out of the earth or the solar system, it depends on how far human science and technology have developed.

After the sun becomes a white dwarf, if the earth is not engulfed by the sun, the temperature of the earth will slowly drop until it drops to about minus 270 degrees. In this long process, because there is no water or air on the earth, there will be no new life! The Earth will eventually become a cold, lifeless ball of rock.

The sun has been burning for 4.6 billion years, which was calculated by the great immortal. How is it calculated?

After the sun burns out, no one knows what the fate of the earth will be. Who knows who is telling myths and lies.

The current history cannot be understood in a thousand years. If you can understand what happened 4.6 billion years ago, I can only say that you are the leader of Tongtian, not an ordinary god.

Everything in the universe can only be imagined through fantasy. Invisible and intangible, all doctrines are based on "reasoning", and this "reasoning" clearly means "say whatever comes to mind."

What astronomers say are myths. If you are not a god or a ghost, you will not understand his myths.

This is what people often say when you see people and talk about people, when you see ghosts and talk about ghosts, when you see gods and talk about myths.

The earth in 5 billion years will indeed be in troubled times. First, the sun has become a red giant, Venus and Mercury must have given up treatment, and even if the earth is not annexed, the surface will become magma... On the one hand, it is expanding and arrogant. The Sun, the Milky Way and Andromeda will collide and merge. The expansion of the universe is accelerating. In 5 billion years, the night sky of the earth will be much darker than it is now, and galaxies and stars will be farther and farther away from us...

If we talk about the sun, this The young man is now officially full of energy and shining, saving the world and spreading his brilliance, but in the future, that is, in about 5 billion years, it will become a red giant and expand at least 200 times. After becoming a red giant, the sun will throw away part of the material, which will later become dust, and the sun will become a white dwarf at this time...

Some friends may ask why the sun will not become a black hole. In fact, the main reason is that the sun will not become a black hole. It's because the sun is far from meeting the standards and is too small... so the sun ends up as a white dwarf. Since all the internal reactions of the white dwarf star have stopped, the white dwarf star will last for tens of billions or even hundreds of billions of years, and our universe is only about 13.7 billion years ago...

What will the earth do then? In fact, if we can’t wait that long, humans will be able to cross galaxies and travel across the universe. In other words, before that time, humans will be extinct... Assume that humans are still living on the earth at that time, and humans still live in places all over the universe. There are indigenous people living on the earth, so they also need to travel across time immediately...

Or... they will not let the sun become a red giant...

Or... the developed civilization of human beings absorbs the energy of the sun, but before one billion years, the sun has become a white dwarf star. As a result, humans will not let go of the white dwarf star, but also want to use it.

Well, it is in line with the characteristics of human beings who rely on mountains to eat mountains and water to eat water.

Groundless worries