for the next 5 billions years?

Question

they said in the next 5 billion years, the sun will be 500 times hotter. how is that possible? because i runs out of fuel and there is not more to use so it should be cooler right?

Answer 1

Hi. If all goes according to theory the Sun will become a red giant and expand to larger than the orbit of Venus. The size increases it's apparent radiation on Earth. Hot hot hot.

Answer 2

Okay basically this is how this works. The sun's surface won't get hotter at all, what will though is the core where the nuclear reactions take place. In about five billion years the sun will start using up it's hydrogen fuel and start burning helium into carbon. As the hydrogen reaction slows down, the energy keeping the sun stable will be lost and gravity will begin to pull the whole thing in on itself. When this happens the core will shrink and heat up (because of the pressure) until Helium starts fusing. Since helium fuses at a much higher temperature then hydrogen, the core will have to heat up about 500 or so times more before the helium starts to burn releasing energy and halting the core's collapse.

Answer 3

Not quite. Hydrogen may be the Sun's fuel, but it isn't a fuel like gasoline where it gradually depletes itself.

The Sun will become what it known as a red giant in 5 billion years: it will not become 500 times hotter. Check the wikipedia article for more info.

Answer 4

Imagine the sun as having a fuel tank. It has fuel to power the reactions. What will actually change is the rate that the sun burns fuel. This will happen while there is plenty left. It's like driving a car faster than normal 5 minutes before running out of gas.

Answer 5

Stellar evolution is counter-intuitive. The bigger a fire, the longer it lasts. But the stars that burn out most quickly are the big ones. The smallest stars, red dwarfs, use up fuel at a much slower rate than larger ones. Some red dwarfs will still be shining 100 million million years from now. In about 1 billion years, the sun will expand and become a red giant, bigger than the Earth's orbit, and the Earth will be uninhabitable.

Answer 6

sun produce energy mainly by chemical and nuclear reactions. and the reaction is getting faster and faster as time goes by.