Apparently when our sun has lived out its entire life, it will pulse and fade away to a white dwarf. It will do this because it will have used up all of its fuel. That being said, since the Hydrogen Fusion is what creates sunlight with Photons, what is it that keeps the white dwarf it will be glowing? What creates the light then?
In: Physics
Think how much energy you need to send a rocket from Earth to space.
Now think what happens if I had the rocket in space and dropped it to Earth. How much energy would it release? The answer is the same amount as if you needed to throw it up to where the rocket is now. We call the energy that is contained in the rocket before you drop it – potential energy.
Now imagine doing the dropping for a whole star to the size of a white dwarf. That’s a whole lot of potential energy being released. This is what heats up a white dwarf.
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