gamma-ray bursts – Quanta Magazine

Extra-Long Blasts Challenge Our Theories of Cosmic Cataclysms

Charlie Wood — Mon, 11 Dec 2023 15:22:13 +0000

On December 11, 2021, a beam of gamma rays — the most energetic form of light — slammed into NASA’s Swift satellite. Within 120 seconds, the satellite had swiveled toward the blast and spotted the glowing embers of a cosmic catastrophe. Ten minutes later, alerts went out to astronomers around the world. Among them was Jillian Rastinejad, a graduate student at Northwestern University.

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Strange Solar Gamma Rays Discovered at Even Higher Energies

Katie McCormick — Mon, 27 Feb 2023 14:55:47 +0000

In 2019, researchers announced that something appeared to be off with the sun. After 10 years of observations, they had concluded that the sun’s high-energy radiation was seven times more abundant than expected. Now a new study based on even higher-energy data has sharpened the picture. Researchers found that the solar gamma-ray excess persists at higher energies. It then drops off at the topmost...

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Brightest-Ever Space Explosion Reveals Possible Hints of Dark Matter

Jonathan O'Callaghan — Wed, 26 Oct 2022 13:50:03 +0000

On Sunday, October 9, Judith Racusin was 35,000 feet in the air, en route to a high-energy astrophysics conference, when the biggest cosmic explosion in history took place. “I landed, looked at my phone, and had dozens of messages,” said Racusin, an astrophysicist at NASA’s Goddard Space Flight Center in Maryland. “It was really exceptional.” The explosion was a long gamma-ray burst...

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Brighter Than a Billion Billion Suns: Gamma-Ray Bursts Continue to Surprise

Jonathan O'Callaghan — Wed, 30 Jun 2021 13:28:27 +0000

In July 1967, at the height of the Cold War, American satellites that had been launched to look for Soviet nuclear weapons tests found something wholly unexpected. The Vela 3 and 4 satellites observed brief flashes of high-energy photons, or gamma rays, that appeared to be coming from space. Later, in a 1973 paper that compiled more than a dozen such mysterious events, astronomers would dub them...

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Long-Missing Midsize Black Hole Flashes Into View

Jonathan O'Callaghan — Mon, 29 Mar 2021 15:00:25 +0000

At the heart of almost every large galaxy lies an object of immense proportions — a supermassive black hole. Up to billions of times more massive than our sun, these titans drive the evolution of the galaxies they inhabit. Yet astronomers can’t figure out how they got so big. Some appear to have formed as early as 600 million years after the Big Bang, when the universe was just 4%

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