Mysterious swirling light gives new insights into black holes

Experts discover crucial evidence that could reveal how magnetic fields behave around black holes

An image that captures streaks of polarised light swirling around a supermassive black hole is providing new insight into how galaxies can project streams of energy thousands of light-years outward from their core.

Black holes are places where the pull of gravity is so strong that even light cannot escape. Most surrounding matter gets sucked in, but some particles escape just moments before they are captured and are blown far out into space.

These bright jets of energy and matter are one of the galaxy’s most mysterious features. Researchers suspect the jets are launched and shaped by magnetic fields, but the evidence for this is limited.

The new observations, based on data collected by the Event Horizon Telescope (EHT) collaboration, which links data from eight radio telescopes in various continents to create an Earth-sized virtual telescope, could help to better understand this phenomenon.

“We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes,” said Monika Moscibrodzka, an assistant professor at Radboud University in the Netherlands and co-author of the research, which was published in the Astrophysical Journal Letters.

The EHT collaboration released the first image of a black hole in 2019, revealing a bright ring-like structure with a dark central region described as the black hole’s “shadow”. The black hole is located in a galaxy called Messier 87 (M87), 55m light-years away from Earth.

After capturing that image, the team discovered that a significant fraction of its surrounding light was polarised – meaning its waves are vibrating in one direction only. The light is thought to become polarised when it is emitted in hot regions of space that are magnetised.

Using the same data as for their first image, they have now analysed that polarised light and are using it to map the magnetic field lines at the black hole’s inner edge, and better understand how these fields act to keep hot gas out of the black hole.

Team member Dr Ziri Younsi at the University College London Mullard space science laboratory said: “These groundbreaking measurements of the polarisation of light produced at the edge of the black hole’s event horizon provide us with exciting new insights into the physical processes by which black holes feed on matter, and how they are able to power such prodigious relativistic outflows as astrophysical jets. In particular, they hint at the role played by magnetic fields in these processes.”

The team found that only theoretical models featuring strongly magnetised gas could explain what they were seeing at the event horizon – the boundary marking the limits of a black hole.

Co-author Dr Jason Dexter, at the University of Colorado in Boulder, US, said: “The observations suggest that the magnetic fields at the black hole’s edge are strong enough to push back on the hot gas and help it resist gravity’s pull. Only the gas that slips through the field can spiral inwards to the event horizon.”


Linda Geddes

The GuardianTramp

Related Content

Article image
Dark energy could be created inside black holes, scientists claim
Conclusion comes after comparison of growth rates of black holes in different galaxies

Ian Sample Science editor

15, Feb, 2023 @5:13 PM

Article image
Black hole found 1,000 light years from Earth
Object found in HR 6819 system is the closest to Earth yet known – and is unusually dark

Nicola Davis

06, May, 2020 @12:00 PM

Article image
From young Mozart to black holes, 350 years of the Royal Society go online

Britain's academy of the sciences marks anniversary with online archive including letters from Newton and Captain Cook

Ian Sample, science correspondent

30, Nov, 2009 @12:05 AM

Article image
Visible light from black holes detected for first time
Scientists observing V404 Cygni discovered that even amateur telescopes are capable of capturing violent outburst from black holes closest to Earth

Ian Sample Science editor

06, Jan, 2016 @6:41 PM

Leader: More black holes

Black holes, it turns out, may not be so dark after all.


19, Jul, 2004 @10:58 PM

American astronomers claim that black holes may not exist

They swallow everything that comes their way and exercise the world's finest minds, but the portrayal of black holes as awe-inspiring celestial menaces may be woefully inaccurate, a team of scientists claim. Indeed, they might not exist at all.

Ian Sample, science correspondent

28, Jul, 2006 @11:07 PM

Article image
Black holes: don't get sucked in

Following the discovery of two supermassive black holes, a quick reminder of the dangers of getting too close to a collapsing star

Alok Jha

11, Dec, 2011 @8:00 PM

Article image
First dormant black hole found outside the Milky Way
VFTS243 has a mass nine times that of the Sun’s and is in a binary system with a companion star

Cash Boyle

18, Jul, 2022 @5:42 PM

Article image
Black hole may have swallowed neutron star, say astronomers
Scientists analyse whether gravitational wave detectors picked up signs of collision

Hannah Devlin Science correspondent

03, May, 2019 @3:56 PM

Article image
Scientists capture image of black hole emitting high-energy jets
Detailed image taken by Event Horizon Telescope of black hole 5bn light years away

Nicola Davis

07, Apr, 2020 @1:00 PM