The life span of the Sun is about 10 billion years, how long is the life of a star?

The lifespan of a star is related to its size and its energy, generally speaking, the larger the star, the higher the energy of the star has a short lifespan, only tens of millions of years, and the sun is a very small star among the stars, so the lifespan is as long as 10 billion years.

The lifespan of a star is related to its mass. The more massive the star, the shorter the lifespan, probably tens of millions of years. The less massive the star, the longer the lifespan.

The age and lifespan of the sun.

The sun continuously radiates energy into space in the form of electromagnetic waves. This energy is released by the fusion of four hydrogen nuclei into a helium nucleus under high temperature and high pressure. We know that the atomic weight of a hydrogen nucleus is, the atomic weight of a helium nucleus is, and the mass of 4 hydrogen nuclei should be.

When 4 hydrogen nuclei fuse into 1 helium nucleus, a unit of mass is lost, of which, 1 gram of hydrogen nuclei is fused into a helium nucleus. This means that solar energy is produced at the cost of consuming mass, and this mass is converted into solar radiation and no longer belongs to the sun. The sun loses about 4 million tons of mass per second, which is simply too small for a huge solar mass.

In the 5 billion years since the birth of the sun, the sun has consumed only mass, and even in another 5 billion years, it will only consume the mass of the sun. But the question is, no matter how massive the sun is, it is still limited, and how long can the sun last for life? What is the impact on the planet?

The life of the sun begins from the nebula, and finally until the red giant, the white dwarf, becomes the dead remains of the sun, this process will take about 10 billion years, that is to say, another 5 billion years will be the death period of the sun, and the earth we live in will be swallowed by the sun when it becomes an expanding red giant. If we humans could survive to that time, we would have to fly to other planets to live.

What is happening inside the sun is nuclear fusion.

The primordial heat of the sun is due to its internal pressure. According to the principle of the law of gravitation, the greater the mass of an object, the greater its gravitational pull. In the early years, when the sun snowballed, as the mass increased, the gravitational pull became stronger, the more material it attracted around it, the more mass was increased, and so on, the mass of the sun became larger and larger.

At the same time, the greater the mass, the greater the internal pressure, so that the temperature continues to rise. Thermonuclear fusion occurs under sufficient pressure (called critical pressure) and a suitable ignition temperature. As the mass of the primordial sun continues to increase, the internal pressure and temperature rise, and after the conditions for thermonuclear reactions are met, the sun begins to shine and become a star.

Generally speaking, for a gas planet to become a star, it must have a certain mass, so that the pressure and temperature inside it can meet the conditions for a thermonuclear reaction, and this mass is called critical mass. A typical example is Jupiter, the largest gaseous planet in our solar system, which is also a gaseous planet composed of hydrogen, but because its mass is less than the critical mass, the internal pressure and temperature cannot meet the conditions for thermonuclear fusion, so it can only be a gaseous planet. However, it is a potential sun, and some scientists speculate that after the destruction of the sun in the future, Jupiter, which is not constrained by the sun, will attract the surrounding planets to form a small solar system by virtue of its position as the leader of the solar system, and at the same time continue to absorb the surrounding matter to increase its mass, and after reaching a critical mass, it will shine and become another sun, but that will be 5 billion years later.

The sun is currently about 100 million years old.

The Sun is a yellow dwarf (spectrum G2V), the lifespan of a yellow dwarf is roughly 10 billion years, and the Sun is currently about 100 million years old. In about 50 to 6 billion years, the Sun's interior will be almost completely depleted of hydrogen and the Sun's core will collapse, causing the temperature to rise, a process that will continue until the Sun begins to fuse helium into carbon. Although helium fusion produces less energy than hydrogen fusion, it is also hotter, so the outer layers of the sun will expand and release a portion of the outer atmosphere into space.

At the end of the process of turning to new elements, the mass of the Sun will decrease slightly, and the outer layers will extend to the current orbit of the Earth or Mars (at which point the two planets will be farther away from the Sun due to the decrease in the mass of the Sun). Come from.