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Space Place. In a snap.

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Where does the sun's energy come from?

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Every 1.5 millionths of a second,

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the sun releases more energy than all humans consume in an entire year.

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Without the sun, there would be no light, no warmth, and no life.

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Its heat influences the environments of all the planets,

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dwarf planets, moons, asteroids, and comets in our solar system.

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How does a big ball of hydrogen create all that heat?

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The short answer is that it is big.

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If it were smaller, it would be just a sphere of hydrogen, like Jupiter.

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But the sun is much bigger than Jupiter.

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It would take almost 1,000 Jupiters to fill it up.

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That's a lot of hydrogen.

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That means it's held together by a whole lot of gravity,

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and that means there is a whole lot of pressure inside of it.

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In fact, the pressure is so intense and the density so great

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that the hydrogen atoms collide with enough force

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that they literally meld into a new element, helium.

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This process, called nuclear fusion, releases energy

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while creating a chain reaction that allows it to occur over and over and over again.

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That energy builds up.

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It gets as hot as 27 million degrees Fahrenheit in the sun's core.

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The energy travels outward through a large area called the convective zone.

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Then it travels onward to the photosphere,

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where it emits heat, charged particles, and light.

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That heat powers the chemical reactions that make life possible on Earth, allows gases

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and liquids to exist on many planets and moons, and causes icy comets to form fiery halos.

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Those particles create a solar wind that pushes against the fabric of interstellar space billions

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of miles away.

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And that light travels far out into the cosmos, just one star among billions and billions.

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Not too bad for a big ball of gas, no?

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Find out more about the Sun at NASA Space Place.