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  • 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.

Space Place in a Snap!

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B1 中級 美國腔

究竟太陽能是從哪來的呢?(Where Does the Sun's Energy Come From?)

  • 14 1
    Sandra 發佈於 2021 年 11 月 02 日
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