Tomorrow or accident, we never know which one will come first, so for human beings, the most important thing is to live every day well.
Live a positive life every day
But not everyone can do it. We are facing an increasingly warming climate , extreme weather that may appear at any time, and watching everyone on the earth gradually disappear A species .
We all think, When will it be our turn ?
Next let’s find out, if nothing happens, how long can humans live? Academician of the Chinese Academy of Sciences said that the earth has 4.5 billion years of life left. Can we survive for that long?
There are still 4.5 billion years left in the life of the earth
Obviously, we have no chance on the earth, and it will perish together .
Earth
Academician of the Chinese Academy of Sciences Wang Jiyang said in a public class that the earth is currently in its prime, still has about 4.5 billion years of life .
We know that Academician Wang actually made the judgment based on the lifespan of the sun.
Sun Lifespan
With the Big Bang, the sun has been born for 4.6 billion years . In the following hundreds of millions of years, the solar system has been giving birth to new planets, and the earth is one of them.
To a large extent, the planets in the solar system and the sun coexist and die.
Solar System
Because the energy of all planets comes from the sun, if the sun disappears, the entire solar system will disappear , not to mention the earth.
According to research observations, the sun belongs to yellow dwarf .
The ingredients that make up stars are generally hydrogen, helium and other heavy elements . The energy generated by the sun is the "burning" of these elements inside it, which is what we call nuclear fusion .
Based on the study of stars, scientists have concluded that the lifespan of yellow dwarfs is generally about 10 billion years. Therefore, based on the evolution model of main sequence stars and the radioactive dating method , it is concluded that the sun has continued to "burn" for 4.6 billion years. Year.
The sun provides heat to the earth
In other words, The sun only has more than 5 billion years of life left.
If the earth and the sun coexist and die, then shouldn’t the earth also have a life span of more than 50 years? Here we have to mention the process of nuclear fusion inside the sun.
In stars, the most abundant hydrogen element is . Therefore, the sun needs to fuse all the internal hydrogen elements into other elements before it can nuclear fusion of the next element.
The nuclear fusion of hydrogen element actually requires the lowest temperature.
Nuclear fusion
In other words, when the nuclear fusion of helium and other elements is carried out later, the heat required for will be higher and higher, and more and more energy will be released at this time.
Therefore, in the last few hundred million years, the sun will gradually become a red giant , and its size will increase rapidly at this time.
The Earth and other Mercury and Venus that are closer to the Earth may gradually fall apart due to ultra-high temperatures, or even be directly swallowed.
The current situation of the earth
So if we don’t consider the accidents that the earth may face, how long can humans survive on the current earth?
How long can humans live?
The earth is facing a huge crisis, I believe everyone has already known it.
The biggest crisis we face is global warming. Once the famous scientist Hawking predicted that human beings can only survive on the earth for 200 years.
Due to human beings' uncontrolled development of the earth's resources and the continuous growth of the population, the earth will turn into a huge fireball in 600 , and it will be difficult for life to exist on the earth.
And the most terrifying thing is that based on the current use of human resources on the earth, it is very likely that in 200 years, the earth will no longer be suitable for human survival.
The earth turns into a fireball
The earth's energy is limited
Even though humans are now trying their best to develop clean energy, they also want to improve the earth's environment.
But even so, we still cannot do without coal, oil and natural gas .
Especially now, oil, as the blood of modern industry, has penetrated into human life in all aspects.
However, according to the current human proven reserves of oil and human demand for oil, there may be another oil crisis erupting on the earth in another 50 years.
Petroleum
And even if oil is exploited to the extreme, it can only be used 00-200 years , and the fate of natural gas and coal is almost the same as that of oil.
Therefore, if no suitable alternative energy is found for , or clean energy cannot be fully used by humans, then we only have a few hundred years left.
Global temperature warming
In the process of using fossil fuels, we are still destroying the earth's environment, and the greenhouse gases they produce will further cause the earth to heat up.
Under the influence of global temperature warming, a large number of glaciers have melted, further reducing the fresh water resources on the earth.
Glaciers melt
and as the permafrost melts, a large number of ancient pathogens and animal remains are exposed.
Many of these viruses are still surviving on the earth. They are likely to cross the ocean and harm the world .
In addition, the process of earth heating has also led to a large number of extreme climate .
For example, in recent years, blizzards, floods, and drought weather have occurred frequently, taking away countless lives.
In the process of global temperature changes, a large number of species have become extinct. According to statistics, on average, 3 species disappear from the earth every hour .
Blizzard weather
Scientists believe that we are now facing the sixth mass extinction of species on earth, and humans, as part of the biological chain, are very likely to disappear with the extinction of these species.
Possible surprises that the earth may face
So if humans never cause global temperature warming and do not use fossil fuels, what kind of surprises will the earth face?
reminds me that the accidents we are going to talk about all come from outside the earth.
The danger of asteroid impact
We know that 65 million years ago, the extinction of the dinosaurs was caused by an asteroid impact, which subsequently triggered a series of volcanic eruptions, tsunamis, earthquakes, etc. on the earth.
Asteroids hitting the earth
These disasters directly led to the extinction of the previous earth's overlords, and then gave humans the opportunity to rise.
In scientists' observations of the universe, they discovered more than 60 stars that may cause harm to the earth.
The red dwarf Gliese 710 located in the direction of Serpens can be said to be the most dangerous star among them.
It is about 63 light years away from the solar system and its mass is 53.5% of the sun.
As early as 1989, scientists discovered that it is running towards us at its own motion and radial speed.
Gliese 710 simulation diagram
At that time, scientists calculated that it might hit the solar system in 1.5 million years. However, in 2018, scientists found that its movement speed was significantly accelerated, and almost only had 1.29 million years left. .
Although scientists now calculate that although the possibility of it directly hitting the solar system is very small, the possibility of it passing through the Oort cloud can reach 86%.
In general, once this impact really occurs, the earth is likely to be hit by asteroids and comets.
In addition to asteroid collisions, we may also face collisions between galaxies. The most likely one is the collision between the Milky Way and the Andromeda Galaxy .
Imagination of galaxy collision
Scientists predict that this collision may occur -4 billion years later , which is hundreds of millions of years before the destruction of the earth.
Scientists once used the Hubble Telescope to observe a galaxy collision that occurred about 65 million light-years away from the earth.
The huge power it produced released a large amount of star clusters , gas and dust and other cosmic materials. If there is extraterrestrial life among them, they may have become extinct.
In addition, there is a Sagittarius dwarf ellipsoid galaxy near the Milky Way. It often comes over and "sticks" with the Milky Way, and every time it comes close, a mass extinction of life will occur.
The location of the Sagittarius dwarf ellipsoidal galaxy
For example, during the Ice Age, it was the result of the Sagittarius's constant proximity.
According to observations, Sagittarius is now only 78,000 light-years away from the Milky Way. Scientists predict that it may collide with the Milky Way in 1.1 billion years.
may then cause the major galaxies in the Milky Way to become a mess, and cause the earth to deviate from its original orbit. Even if the earth does not disappear, may not be in the habitable zone , which will make the earth look like other planets All the same, it became dead silence.
The earth may have become lifeless
In other words, whether it is accidental or non-accidental, the earth may eventually perish early, and humans will have no chance to survive on the earth for such a long time.
Therefore, for humans, if they want to continue their lives and civilization, they can only find a planet in the universe with a similar environment to the earth. But obviously, this is not an easy task.
