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How does a supernova happen?

A supernova is the explosive death of a star. When a massive star runs out of fuel, its core collapses and rebounds in a colossal explosion — briefly outshining a whole galaxy and scattering elements that form new stars, planets, and even us.

See it in motion.
Watch a 2-minute animated lesson that shows exactly how supernovae works.
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Step by step

  • 1It's the explosive death of a massive star.
  • 2The core collapses, then violently rebounds.
  • 3It can briefly outshine an entire galaxy.
  • 4It scatters elements that seed new stars and planets.

Frequently asked questions

How does a supernova happen?
A massive star exhausts its fuel, its core collapses, and it explodes in a brilliant burst of energy.
Why are supernovae important?
They forge and scatter heavy elements across space — the raw material for planets and life.
How bright is a supernova?
For a short time it can shine as brightly as billions of stars, outshining its host galaxy.

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