Why stars like the sun can have so much energy to burn for billions of years?

Question

Why stars like the sun can burn for billions of years, generating so much energy to illuminate everything in its system and more, without burning out?

Answer 1

The sun's energy source is a fusion reaction chain. Fusion converts some of the energy involved in binding atoms to light which is emitted (to us and everything else). The reason it can "burn" for so long is because it has a lot of material (mass) to fuse. Hydrogen can fuse to helium, helium to berylium and etc up to iron. Stars start out as 99% hydrogen and there's a lot (our sun is 10^30 kg of hydrogen), and you don't lose much mass in the fusion process, so depending on how fast it uses hydrogen/helium/etc... it can burn for a couple hundred thousand years (blue white super giants) to billions of years (red dwarfs).

Hope this helps.

Answer 2

This is like asking why a 32 year old hasn't died yet. You may want to research the life cycle and the mechanism's of stars. Stars of different masses have different life cycles and deaths. The equilibrium process in our sun works as follows. The sun is a big ball of gases and elements which causes it to shrink under it's own weight. As it shrinks, it gets hotter. As it gets hotter in the core, Hydrogen will fuse into Helium createing an outward pressure. The sun will stop shrinking when the pressure created by the fusion is enough to balance it's weight. If there is too much fusion at any point in time the sun will expand and cool off some causing less fusion and so it will shrink back to it's equilibrium size. If there is too little fusion the sun will shrink, get hotter and more fusion will ensue, again keeping the sun at it's equilibrium size. There is enough hydrogen left to create Helium using this process for many billions of years but it will start running out. When it's starts running out of hydrogen, the sun will shrink and get hotter until Helium begins to fuse. The sun will have a new equilibrium size and temperature until it starts fusing into Iron. After the element Iron, it takes more energy to fuse the elements than what is released by fusing them. This is important because eventually the fuel will run out again and the sun will shrink. However, this time, the increased temperature caused by the shrinkage will not produce enough fusion energy to stop the ensueing collapse. Momemtum will increase faster than fusion can keep up with. There will be a point when the star will basically bounce off itself allthewhile fusion is creating elements as heavy as uranium. It will then explode into a supernovae and create a nebula of heavy elements from which new planets and new people can form. We are all made of stars. Again, a lot depends on the size of the star. Some stars will leave a black hole at it's core (caused by the explosion and implosion of the core, some will leave a white dwarf, and some a neutron star). These objects can be superdense obects only a few thousand meters across.

Answer 3

Stars will burn out, eventually. But they have so much mass to start with, and the energy is one of the most efficient way to produce power -- fusing hydrogen -- that this can keep going for billion of years.
Actually, bigger stars burn faster; a star twice times as heavy as our sun is producing power at a rate 25 times greater, so will burn out in about 1/12 the time or so.

Answer 4

The end is drawing near. Now the Sun has to rearrange its internal structure all over again, as its source of energy is once again the central core. It will contract back to a bit larger than its original radius and will give off ten times as what we are used to now. This phase only lasts another 500 million years, as there are a lot fewer helium nuclei (it took four hydrogen nuclei to make one helium nucleus, and three helium nuclei to make up one carbon nucleus) and the energy production is much less efficient.

Answer 5

Fusion. With each conversion of two hydrogen atoms to a Helium atom mass is changed into energy. Using the formula E=MC^2. Even a little bit of mass will yield an immense amount of energy considering c=3x10^8, which is a huge number, and it's squared. That's why.

Answer 6

Because of the amount of fuel (hydrogen) they have, and how slowly the heat leaks from the central reactor to the surface
BTW, the amount of heat output by the sun is rather low. If there was a mass of human beings as massive as the sun, they would output more heat than the sun does!!! This is because the sun's surface, compared to the mass of the sun is very small. Your surface, compared to your mass is quite large, ;-)

Answer 7

They generate the things they need for fuel inside the core.
A star like our sun produces hydrogen and other elements inside and that energy takes a million or so years just to reach the surface of the sun due to the high magnetic field it generates

Answer 8

they do burn out at one point. the process that ensures the constant generation of light and heat is called fusion, it's a very violent reaction.but when hydrogen is depleted it will turn into a huge red giant, the extreme temperatures on earth will have killed all life, and because it is to small to turn into a black hole the process of fusion will continue until the new element created will be iron, and our sun will become a white dwarf.

Answer 9

the bottom line is that e=mc^2

c being the speed of light, that makes c^2 a really big number

the m in the equation is the mass of the sun (or at least the mass of a primary componant), and this is also a very very big number

a little big of mass can be expressed as a huge amount of energy

a beyond huge mass like the sun can be expressed as a huge amount of energy for a really really long time

the sun, and stars like it, do eventually burn out but, as you point, out, they put out lots of energy over lots of years before doing so

Answer 10

Because it has trillions and trillions of of tons of hydrogen. As much mass as 300,000 earths.

Actually someone asked this before and this answer was posted:
Even though the Sun looses over 4,000 million tons of mass every second, compared to the total mass of the sun, which is about 2,000,000,000,000,000,000,000 million tons, that isn't much. Even loosing 4,000 million tons per second for 10,000 million years only results in the Sun loosing 0.00006% of its mass!