First off, we are lucky because the sun has
a very long time left to live! Scientists
estimate that the sun is currently about 4.5
billion (that's 4,500,000,000 years) years old and
has about 5 billion years left to burn. That means
that the sun is not yet even halfway through
The sun is made out of hydrogen and helium
atoms. On Earth, hydrogen and helium are gases; in
fact, helium is the gas that is used to inflate
birthday balloons that float in the air. However,
in the sun, hydrogen and helium are so tightly
packed into one region of space that the hydrogen
actually starts to act as a fuel that "burns"
to turn into additional helium. When this hydrogen
"burns" into helium, a tremendous amount of light
and heat is released. This is how the sun is able
to provide the Earth with light and warmth.
The sun will eventually burn through all of the
available hydrogen and will have no more fuel to
continue in its current state, just like cars will
eventually run out of gasoline if they are not
filled up. At this point, the sun will begin to
rapidly change. Scientists think that the sun will
begin to instead burn the remaining helium as
fuel, which will cause the sun to get much larger,
perhaps even large enough to capture the Earth.
Check out the following
for an illustrated video that shows what might
happen in 5 billion years, after the sun runs out
of hydrogen fuel. Can we survive the sun's
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