Category Astronomy/Space

Astrophysicists explore our galaxy’s magnetic turbulence in unprecedented detail using a new computer model

A close up of colourful swirls and lines, a composite image of the Phantom Galaxy.
A composite image of the Phantom Galaxy and (inset) a high-resolution simulation of galactic turbulence with magnetic field lines in white. Photo: ESA/Webb, NASA & CSA, J. Lee and the PHANGS-JWST Team; Acknowledgement: J. Schmidt; Simulation: J. Beattie.

“Turbulence remains one of the greatest unsolved problems in classical mechanics,” says James Beattie, a postdoctoral researcher at the Canadian Institute for Theoretical Astrophysics (CITA) in the Faculty of Arts & Science at the University of Toronto, who also holds a joint appointment at Princeton University.

“This despite the fact that turbulence is ubiquitous: from swirling milk in our coffee to chaotic flows in the oceans, solar wind, interstellar medium, even the plasma between galaxies.

“The key distinction in astro...

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Universe decays faster than thought, but still takes a long time

Uiteenvallende neutronenster

The universe is decaying much faster than thought. This is shown by calculations of three scientists at Radboud University on the so-called Hawking radiation. They calculate that the last stellar remnants take about 10^78 years (a 1 with 78 zeros) to perish. That is much shorter than the previously postulated 10^1100 years (a 1 with 1100 zeros). The researchers publish their findings, with a wink and dead-seriously, in the Journal of Cosmology and Astroparticle Physics.

The research by black hole expert Heino Falcke, quantum physicist Michael Wondrak, and mathematician Walter van Suijlekom (all from Radboud University, Nijmegen, the Netherlands) is a follow-up to a 2023 paper by the same trio...

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Quasars don’t last long—so how do they get so massive?

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Artist’s illustration of a quasar. (Credit : NASA)

Quasars represent some of the most luminous and energetic phenomena in the universe. These distant powerhouses are driven by supermassive black holes—colossal gravitational engines with masses millions to billions of times that of our sun—which actively devour surrounding matter at incredible rates.

As gas, dust, and stellar material spiral inward through an accretion disk superheated to millions of degrees, this matter releases tremendous energy across the electromagnetic spectrum before crossing the event horizon. The resulting emissions can outshine entire galaxies despite originating from a region no larger than our solar system.

The discovery of billion-solar-mass black holes in distant quasars challenges conventional gr...

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Hubble pinpoints roaming massive black hole

Six-panel illustration marked "Artist's Concept." The upper left panel shows the silhouette of supermassive black hole that is adrift inside a galaxy. The middle upper panel shows a yellow star drifting near the black hole. The three following panels show the star being shredded in bright white concentric streamers followed by a white explosion. the bottom right panel is an external view of the galaxy showing a bright white star-like object that is the site if the explosion as viewed in X-rays and visible light.
This six-panel illustration of a tidal disruption event around a supermassive black hole shows the following: 1) A supermassive black hole is adrift inside a galaxy, its presence only detectable by gravitational lensing; 2) A wayward star gets swept up in the black hole’s intense gravitational pull; 3) The star is stretched or “spaghettified” by gravitational tidal effects; 4) The star’s remnants form a disk around the black hole; 5) There is a period of black hole accretion, pouring out radiation across the electromagnetic spectrum, from X-rays to radio wavelengths; and 6) The host galaxy, seen from afar, contains a bright flash of energy that is offset from the galaxy’s nucleus, where an even more massive black hole dwells.
Artwork: NASA, ESA, STScI, Ralf Crawford (STScI)

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