Space Place in a Snap!
Where does the Sun's energy come from?
Every 1.5 millionths of a second the Sun releases
more energy than all humans consume in
an entire year.
Without the Sun there would be no light,
no warmth and no life.
It's heat influences the environments of all
the planets, dwarf planets, moons, asteroids
and comets in our solar system.
How does a big ball of hydrogen create all that
heat? The short answer is that it is big.
If it were smaller it would be just a
sphere of hydrogen like Jupiter, but the
Sun is much bigger than Jupiter. It would
take almost 1,000 Jupiter's to fill it
up. That's a lot of hydrogen. That means
it's held together by a whole lot of
gravity, and that means there is a whole
lot of pressure inside of it. In fact
the pressure is so intense and the
density so great that the hydrogen atoms
collide with enough force that they
literally meld into a new element... helium.
This process called nuclear fusion
releases energy while creating a chain
reaction that allows it to occur over and
over and over again. That energy builds
up. It gets as hot as 27 million degrees
Fahrenheit in the Sun's core. The energy
travels outward through a large area called
the convective zone. Then it travels
onward to the photosphere where it emits
heat, charged particles and light. That
heat powers the chemical reactions that
make life possible on Earth, allows gases
and liquids to exist on many planets and
moons and causes icy comets to form
fiery halos.
Those particles create a solar wind that
pushes against the fabric of
interstellar space billions of miles away...
And that light travels far out into the
cosmos, just one star among billions and
billions. Not too bad for a big ball of
gas no? Find out more about the Sun at
NASA Space Place.
