neutron stars – 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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A Hint of Dark Matter Sends Physicists Looking to the Skies

Jonathan O'Callaghan — Tue, 19 Oct 2021 14:44:10 +0000

Approximately 85% of the mass in the universe is missing — we can infer its existence, we just can’t see it. Over the years, a number of different explanations for this “dark matter” have been proposed, from undiscovered particles to black holes. One idea in particular, however, is drawing renewed attention: the axion. And researchers are turning to the skies to track it down.

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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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Squishy Neutron Star Setback Dampens Hopes of Exotic Matter

Jonathan O'Callaghan — Wed, 26 May 2021 14:46:35 +0000

In the known universe, there is nothing quite like a neutron star. Born from supernovas, these objects contain a star-size mass in a city-size space. This unique trait has led scientists to believe that some extreme physics might take place in their innards — perhaps even the dissolution of neutrons themselves into a softer goo known as quark matter. Yet we cannot peer inside neutron stars...

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‘Unicorn’ Discovery Points to a New Population of Black Holes

Jonathan O'Callaghan — Wed, 27 Jan 2021 15:08:46 +0000

Almost a decade ago, Feryal Özel and her colleagues noticed something odd. While a variety of possible black holes had been found in our galaxy, none appeared to fall below a certain size. “There seemed to be a dearth of black holes below 5 solar masses,” she said. “Statistically, this was very significant.” Since Özel, an astrophysicist at the University of Arizona, published a paper on the...

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