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Scientists Discover Secrets of Swirling Plume-Like Structures Beneath Greenland Ice Sheet

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For years, glaciologists have been intrigued by the peculiar plume-like structures hidden beneath the Greenland Ice Sheet. Recent research conducted by scientists from the University of Bergen, NASA’s Goddard Space Flight Center, and the University of Oxford indicates that these enigmatic features are the result of thermal convection—an intriguing process typically associated with Earth’s mantle.

Location of a large plume-like structure (triangle) within the Greenland Ice Sheet. Credit: Leysinger Vieli et al., doi: 10.1038/s41467-018-07083-3 / Law et al., doi: 10.5194/tc-20-1071-2026.

“Typically, we perceive ice as a solid material, so the revelation that parts of the Greenland Ice Sheet experience heat convection—similar to cooking pasta— is both extraordinary and fascinating,” said study co-author Professor Andreas Born from the University of Bergen.

“The realization that thermal convection can occur within ice sheets defies our expectations,” remarked lead author Dr. Robert Loh, also from the University of Bergen.

“However, the ice is at least a million times softer than Earth’s mantle, making the physics align. It’s truly a remarkable phenomenon in nature.”

“These findings could play a crucial role in reducing uncertainties in models predicting ice sheet mass balance and sea level rise,” added Professor Born.

Deep ice is found to be approximately ten times softer than previously assumed, but this does not imply a faster melting rate.

“Enhancing our understanding of ice physics is vital for greater certainty regarding future conditions; nonetheless, softer ice alone does not guarantee accelerated melting or increased sea levels. Further studies are necessary to explore this,” Dr. Loh emphasized.

Although these findings do not predict imminent disasters in Greenland or elsewhere, they underscore the complex and dynamic nature of this region.

“Greenland and its ecosystem are indeed unique,” Dr. Loh commented.

“The ice sheet is over 1,000 years old and is the only one on Earth that coexists with a culture and established communities along its edges.”

“Understanding the processes beneath the ice will better equip us to handle the changes occurring along coastlines globally.”

Read more about the research in the upcoming publication in Cryosphere this month.

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R. Law et al. 2026. Investigating the conditions under which convection is likely to occur within the Greenland Ice Sheet. Cryosphere 20: 1071-1086; doi: 10.5194/tc-20-1071-2026

Source: www.sci.news

Revealing the Magnetic Field Swirling Around Our Galaxy’s Black Hole through a New Perspective

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Black hole Sagittarius A* seen in polarized light

European Southern Observatory (ESO)

This is a supermassive black hole at the center of a galaxy that we have never seen before. The image reveals a swirling magnetic field around Sagittarius A* (Sgr A*), suggesting it may be producing jets of high-energy material that astronomers have not yet seen.

This photo was taken by a network of observatories around the world operating as a single giant telescope called the Event Horizon Telescope (EHT). In 2022, the first images of Sgr A* were produced, revealing light emanating from swirling hot plasma set against the dark background of a black hole's event horizon. There, light cannot escape the extreme gravity.

Now, EHT researchers Jiri Yunshi The researchers from University College London measured how this light is polarized, or the direction of the electromagnetic field, and showed the direction and strength of the magnetic field around Sgr A*.

This image is very similar to the magnetic field of M87*, the first black hole studied by EHT. Given that M87* is about 1,500 times more massive than Sgr A*, this suggests that supermassive black holes may have similar structures regardless of their size, Yunshi says.

The two black holes photographed by the Event Horizon Telescope are strikingly similar.

European Southern Observatory (ESO)

One major difference between M87* and the black holes in our galaxy is the absence of visible high-energy jets visible from Sgr A*. This lack has long puzzled astronomers, but the fact that Sgr A* has a magnetic field like M87* suggests that our galaxy's black hole may also have jets. It suggests.

“There are very interesting hints that there may be additional structures,” Yunshi says. “I think something very exciting could be happening at the center of the galaxy, and we need to track these results.”

This makes sense given other evidence for jets that may have existed long before the galaxy's history, such as Fermi bubbles, large balls of X-ray-producing plasma above and below the Milky Way. Masu.

In addition to revealing potential hidden jets, the properties of magnetic fields also solve other astrophysical mysteries, such as how particles like cosmic rays and neutrinos are accelerated to ultrahigh energies. This could help solve the problem, Yunshi said. “Magnetic fields are the basis of all of this. Anything that yields further insight into how black holes and magnetic fields interact is of just fundamental importance to astrophysics.”

Yunshi and his colleagues hope to use a larger telescope network and more advanced equipment to take more images of Sgr A*, which will help them understand the nature of the magnetic field and how it directs the jet. This will deepen your understanding of what is being generated. EHT plans to begin these observations in April, but processing the data could take several years.

References: Astrophysics Journal LetterDoi: 10.3847/2041-8213/ad2df0 &DOI: 10.3847/2041-8213/ad2df1

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Source: www.newscientist.com