Why is it so hot this year? Is the sun going to explode?

According to media reports, Vandel Meyer, a Dutch astrophysicist, believes that the sun is undergoing changes similar to those before the supernova explosion, based on the data of solar nuclear temperature changes in recent years. Vangil Meyer believes that the temperature of the sun's core is usually 27 million degrees, but it has risen to 49 million degrees in recent years. If the core of the sun continues to heat up at this rate and this process is irreversible, then the sun will explode in about six years.

Is this appalling statement true? Therefore, the author discussed with Fang Cheng, an expert in solar research and an academician of China Academy of Sciences.

There are countless stars in the colorful starry sky. The Milky Way, where our solar system is located, has about 1000 billion stars. Their shapes are varied and varied. The largest star diameter can accommodate Saturn's orbit, and the diameter of a small star can be smaller than that of the earth. The luminosity of stars is even different. Bright stars can be ten million times brighter than the sun, while dark stars are too dark for us to find.

In recent years, the study of stars shows that the difference in the mass of stars is relatively small, the heaviest star is only ten times that of the sun, and the lightest star is only one tenth of the weight of the sun. Moreover, many observational facts show that the quality of a star determines the life of a star. All stars are formed in gas or dust clouds. Primitive stars are a huge mass of gas and dust. Under the action of gravity, the protostar gradually shrinks due to polymerization, and the temperature at the center is getting higher and higher. When it reaches 7 million degrees, the thermonuclear reaction of four hydrogen atoms to synthesize one helium atom begins, and the star will get hotter and hotter, eventually becoming a glowing star. Thermonuclear reactions generally only occur in the center of the star, and the heat inside the star is conducted to the outside of the star through radiation and convection.

The central temperature of the sun is about 654.38+05 million degrees. This data is the result of theoretical calculation and we can't directly observe it. Stars with too small mass can only form dwarfs because of weak polymerization and high central temperature, so the development process is very slow and the life span is very long. Primitive stars with a mass less than 8% of the mass of the sun cannot evolve into stars. For example, although Jupiter is extremely rich in hydrogen, its mass is only one thousandth that of the sun, so it is impossible for Jupiter to evolve into a star. Due to the strong polymerization, massive stars will form extremely high temperatures in the center of the stars, causing intense thermonuclear reactions and rapidly consuming hydrogen fuel. The life span of a superstar is relatively short. The estimated life span of a star ten times the mass of the sun is only 20,000 years. Our sun is a medium-mass star with a life span of 654.38+00 billion years. At present, the age of the sun is about 4.6 billion years, which is in the prime of life and in a very stable period, so it has not erupted at all.

Of course, the sun will also change. For example, the sunspot period of the sun is about 1 1 year. In the peak year of solar activity, there are many sunspots and prominences on the surface of the sun, and sometimes there will be larger flares or sunspots, also known as solar bursts. In fact, it is only a small local phenomenon on the surface of the sun. Observations show that the change of solar radiation caused by solar activities is very small, generally not more than three thousandths of the total solar radiation, so the impact on the earth is very small. The sun may have a change cycle of hundreds of years, and the change range may be even greater. Billions of years of geological changes and life evolution on the earth show that the radiation changes of the sun have been very stable in the past billions of years.

Everything starts and ends, and the sun is no exception. Hydrogen fuel on the sun can also ensure that the sun shines for more than 5 billion years. Some people describe the final evolution of the sun like this: after the hydrogen fuel is used up 10%, the sun will begin to shrink; When the central temperature continues to rise and reaches 1 100 million degrees, helium begins to ignite and burn, synthesizing heavier elements, and then continues to shrink; The central temperature continues to rise, igniting the nuclear reaction of heavier elements ... Eventually, when the solar shell cannot resist the internal pressure, it will explode, the central part of the sun will evolve into a white dwarf, and the solar shell will evolve into a planetary nebula. Some people may be pessimistic about such a result. Actually, we don't have to worry at all. The history of mankind is less than 10 thousand years, and the level of science and technology of mankind is improving rapidly. Humans will have stronger ability to control and transform nature. Maybe hundreds of millions of years later, our descendants will move to other planets or the universe! The sun is a star.

Stars are not eternal, just like us mortals, stars live and die, and their lives can be roughly represented by a picture. The length of a star's life, what changes a star will have when it is old, and what it will look like after death are all closely related to its quality. So what's important about the quality of a star? Roughly speaking, it represents the amount of star fuel, and astronomers usually take our nearest sun as the standard. Stars whose mass is more than ten times that of the sun are called massive stars, and those whose mass is less than half that of the sun are called small-mass stars.

A massive star spent a short life brilliantly and ended in a heroic supernova explosion. Throughout his life, the sun will end up in a planetary nebula and leave the star world sobbing. Brown dwarf is a failed star with too little mass.

At first glance, massive stars contain more fuel, as if they should live the longest. However, they are natural black sheep, and the speed of consuming fuel is dozens to thousands of times that of the sun. So after millions to tens of millions of years of profligacy, we exhausted all our possessions and ended up with a death ceremony of supernova explosion.

The sun that provides light and heat for human beings can live for about10 billion years. For the 5 billion-year-old sun, it still has a life span of 5 billion years! This has been long enough for us humans. Small stars can live for tens of billions of years, but they are real misers. They scrimped and saved until they died.