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(Music throughout)

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This pulsar’s vast gamma-ray halo may explain a key observation about antimatter near Earth.

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[Big Dipper to scale]

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Pulsars are rapidly spinning neutron stars, the superdense remnants of supernovae explosions.

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NASA’s Fermi mission has observed one nearby pulsar, Geminga, for more than 10 years.

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The data are now so detailed that when scientists remove background sources…

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…Geminga’s faint but huge gamma-ray halo emerges.

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This halo precisely matches computer models that account for positron production.

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Positrons are antimatter versions of electrons. They’re found near Earth but have no clear origin.

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Scientists suspected pulsars to be positron sources. This study confirms it.

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As it turns out, Geminga is likely the greatest positron source for Earth.

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It alone could produce 20% of the positrons at an energy of 1 TeV seen in orbit.

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So pulsars not only shine in the highest-energy light, they also glow in antimatter.