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An unusual outburst about 1 billion light-years away

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right here, has rocked scientists’ understanding

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of the universe’s most powerful events.

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Some of these are the source of the heavy elements in the cosmos,

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like gold. For decades,

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scientists have divided these explosions, called gamma-ray bursts,

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into two groups – long and short GRBs.

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Long bursts produce a flare of gamma-rays

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the highest-energy form of light, that last

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two or more seconds. They’re thought to be caused

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by black holes forming at the center of massive collapsing

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stars and are followed by supernova explosions.

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Short bursts, on the other hand, last less than two seconds,

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are likely caused by neutron star mergers, and are followed by

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flares of visible and infrared light called kilonovae.

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music

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But a recent event has scientists rethinking these categories.

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On Dec 11, 2021, NASA’s

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Swift and Fermi telescopes observed a 50-second-long

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gamma-ray burst followed by the clear signs

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of a kilonova. It’s called GRB 211211A.

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It was later studied by the Hubble Space Telescope

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along with a number of other observatories.

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Scientists don’t yet know how a burst caused by a neutron star

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merger could produce gamma rays for so long.

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Maybe instead of two neutron stars,

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one of the objects was a black hole.

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Kilonovae are a known source of heavy elements like iodine,

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which was essential for the development of life on Earth.

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But scientists thought they were only associated with short bursts.

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GRB 211211A shows,

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for the first time, that kilonovae can accompany both

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short and long bursts.

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After 50 years of studying these events, scientists are still learning

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new things about their effects on the cosmos.