Everything in the universe, even the universe itself, cannot exist forever, and everything will have an end.
The death of the sun is the death of the solar system
The Sun accounts for 99.86% of the total mass of material in the solar system and is the deserved master of the solar system. The direction and progress of the sun's evolution determine the fate of the solar system. If the state of the sun changes drastically one day, then other celestial bodies in the solar system will be seriously affected, and life on Earth and even on Earth will probably cease to exist.
Not alarmist yet! By observing changes in other stars, astronomers have figured out how stars evolve throughout their life cycle.
According to the evolutionary theory of stars, stars of mass like the Sun have a lifespan of about 10 billion years. The Sun is now in the main sequence star stage, 4.6 billion years old, and has about 5 billion years of lifespan.
The Sun now relies on hydrogen in its core region to slowly coalesce to helium, which has lost more than 100 Earth-mass materials over the past 4.6 billion years.
The sun is now in middle age, and when it reaches old age, the hydrogen in its core region is almost consumed, at which point the balance of gravitational and radiation pressure is broken, and the sun's interior collapses. This will cause the temperature and pressure inside it to rise, at which point the hydrogen outside the sun's core region will also begin to ignite and fuse, and the sun's outer shell will continue to expand to become a red giant.
At that time, its radius was about 100 to 200 times that of today, and its volume would expand millions of times that of today, and Mercury and Venus would be engulfed by it. The Earth is about 150 million kilometers away from the Sun, when the Surface of the Sun may touch the Earth's orbit, and the Earth will be scorched, if not engulfed.
The Sun does not stay too long in the red giant phase, and as the outer shell expands, the Sun's core also contracts, causing the helium in the core region to reach fusion conditions. In the process, because the fusion is too intense, the sun will throw more than half of its mass, forming a planetary nebula, and eventually the core area of the sun will become a white dwarf.
White dwarfs are extremely dense stars whose internal material exists in a degenerate form, up to 10 tons per cubic centimeter, and whose maximum mass cannot exceed the Chandrasekhar limit (1.44 solar masses).
By this time, nuclear fusion has completely stopped, but white dwarfs are still able to emit light with their own residual heat. The Sun will remain in the white dwarf stage for a very long time, slowly cooling down, and eventually becoming a black dwarf that is still the predicted by theory until the universe dies.
When the Sun becomes a white dwarf, will other objects in the Solar System continue to exist?
The scientists pointed the telescope in the direction of the constellation Virgo and found a white dwarf star called "SDSS J1228+1040" 413 light-years from Earth. Observations have found that the mass of the white dwarf is about 70% of the mass of the Sun, and scientists have found a "circumference disk" of gas, dust, rock, asteroids and so on around the white dwarf.
Using Doppler tomography, scientists have discovered that there is also a celestial object called "SDSS J1228+1040b" hidden in that circumstellar disk. Observational data show that the submerged object in debris is about 500,000 kilometers away from its parent star, which is only a little farther than the Earth-Moon distance (about 380,000 kilometers), and it takes only 2 hours to orbit its parent star.
It has a diameter of about 600 kilometers and a density of more than 7.7 grams per cubic centimeter and a maximum of 39 grams per cubic centimeter. The average density of the Earth's core is about 10.7 grams per cubic centimeter, and the density of that object is exactly in the core density range of a rocky planet like Earth.
Scientists have a reasonable speculation that SDSS J1228+1040 was a main-sequence star with a greater mass than the Sun a long time ago, and that SDSS J1228+1040b was supposed to be a planet around SDSS J1228+1040, but the life of the star SDSS J1228+1040 came to an end, and in the process of this series of changes, the planets around the star that were relatively close to it were destroyed, and the circle of "star circumference" It is the remnants of the planet, and SDSS J1228+1040b is the wreckage left by the destroyed rocky planet.
The current state of the star system in which the white dwarf SDSS J1228+1040 was originally located is the state of the solar system 5 billion years from now.
When the sun reaches the end of its life, its mass will decrease, its gravity will weaken, and the orbits of the eight planets in the solar system will shift outward. However, in the process of the sun becoming a white dwarf, mercury and Venus should be swallowed up.
As for Earth, it may be destroyed like SDSS J1228+1040b, and if it is not destroyed, then the Earth will become a bare, scorched planet like Mercury today.
Planets outside of Earth's orbit will still exist peacefully and continue to orbit newly born white dwarfs, but there should never be a new planet with life in the solar system.
According to scientists' theories, after about a billion years, the sun will enter an aging period and slowly evolve into a red giant, and the average temperature of the Earth will rise accordingly.
But before that happens, humans may have gone extinct. If human beings still existed at that time, the level of science and technology must be very advanced, and they would have already left the earth and become an interstellar civilization.
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