The sun in 5 billion years

Judging from the current time, 5 billion years is still too far away. The history of mankind is only 6 million years, and civilization in the true sense is about 5,000 years old. Now many people worry about whether the earth can survive for hundreds of years under the destruction of human beings. Is it too far to think about what will happen 5 billion years from now?

Any burning has an end, and so does the sun. The current sun is in its prime-major-main-sequence stage, and this stable period will continue for another 5 billion years. After 5 billion years, the hydrogen fuel of the sun will gradually burn out, the core will shrink, become more and more dense and hot, and the outer layer will expand rapidly. It will enter the "late years" of life - the era of red giant stars. At that time, the sun became larger and swallowed the orbits of Mercury and Venus one after another, and the earth could not escape, it would be swallowed up and disintegrated.