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NASA's Fermi Gamma-ray Space Telescope

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has observed
something it's never seen before.

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A discovery
that helps explain an astronomical

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mystery.

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Supernovae are exploding stars.

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They most often occur
when the core of a massive star runs

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out of fuel and collapses.

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But in the past couple of decades,

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astronomers have found supernovae
up to 100 times brighter than usual.

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The mystery is how these superluminous supernovae

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were powering up.

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Astronomers looked at six
near superluminous

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supernovae to occur
during Fermi's mission.

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Only one, in 2017,

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shows evidence of gamma rays,
the highest-energy form of light.

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Analysis of these findings
clearly favors one explanation.

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The extra power comes from a spinning,
supermagnetized neutron star —

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called a magnetar — formed in the star's
collapse.

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The magnetar’s intense magnetic field

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accelerates particles
that ultimately produce gamma rays.

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At first, the debris absorbs this emission
and converts it

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to visible light,
boosting the brightness of the blast.

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After about three months,
the debris thins out enough

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that the gamma rays can leak out
and travel to us.

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With this observation,
Fermi has helped solve a cosmic mystery

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and has added another class of gamma
ray sources

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to its repertoire.