supernovas – Quanta Magazine

Clashing Cosmic Numbers Challenge Our Best Theory of the Universe

Liz Kruesi — Fri, 19 Jan 2024 15:44:49 +0000

In the early 2000s, it seemed that cosmologists had solved the largest and most complex puzzle of all: how the universe works. “There was this amazing moment when all of a sudden, all the pieces in cosmology snapped together,” said J. Colin Hill, a theoretical cosmologist at Columbia University. All the ways of studying the universe — mapping galaxies and their larger structures...

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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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Shadows in the Big Bang Afterglow Reveal Invisible Cosmic Structures

Zack Savitsky — Mon, 13 Mar 2023 13:51:05 +0000

Nearly 400,000 years after the Big Bang, the primordial plasma of the infant universe cooled enough for the first atoms to coalesce, making space for the embedded radiation to soar free. That light — the cosmic microwave background (CMB) — continues to stream through the sky in all directions, broadcasting a snapshot of the early universe that’s picked up by dedicated telescopes and even revealed...

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What Lights the Universe’s Standard Candles?

Lyndie Chiou — Wed, 08 Feb 2023 15:24:50 +0000

Every year, around 1,000 Type Ia supernovas erupt in the sky. These stellar explosions brighten and then fade away in a pattern so repeatable that they’re used as “standard candles” — objects so uniformly bright that astronomers can deduce the distance to one of them by its appearance. Our understanding of the cosmos is based on these standard candles. Consider two of the biggest mysteries in...

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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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