Nature can get brutal. On a cosmic scale, things get even more destructive—leaving behind carnage made of stellar dust the size of an entire planet.
Astronomers using the Hubble Space Telescope spotted a white dwarf—the remnant of a dying star’s core—enjoying a meal of some fragment researchers later identified as coming from a Pluto-like object. According to a paper on the finding published September 18 in Monthly Notices of the Royal Astronomical Society, astronomers seemingly caught the dwarf near the tail end of its meal; some time ago, the dwarf’s intense gravitational pull likely snatched an icy planet from its regular orbit.
What’s more, further analysis of the doomed object revealed that its chemical composition included key elements such as carbon, sulfur, nitrogen, and oxygen—suggesting that, before its demise, the tiny planet may have held some water on its surface.
A ‘cosmic crime scene’
The atmosphere of a white dwarf typically consists of hydrogen and helium. But this particular dwarf, WD 1647+375, carried an unusual supply of volatiles, or chemical substances with low melting points. That told the researchers that something was off.
“White dwarfs act like cosmic crime scenes,” study lead author Snehalata Sahu said in a release. “When a planetesimal [small solid objects thought to form planets] falls in, its elements leave chemical fingerprints in the star’s atmosphere, letting us reconstruct the identity of the ‘victim.’”
So the team embarked on some detective work. One thing that stood out to them was the abundance of nitrogen in WD 1647+375, which the researchers explained was a “particularly important chemical fingerprint of icy worlds.” The dwarf’s oxygen gain was also much higher than it would have been had the victim been a rocky object.
“We know that Pluto’s surface is covered with nitrogen ices,” Sahu added in a Hubble statement. “We think that the white dwarf accreted fragments of the crust and mantle of a dwarf planet.”
From Hubble’s ultraviolet signals, the team was able to deduce that the star’s meal had been ongoing for at least the last 13 years, consuming the object at a rate of around 440,925 pounds (200,000 kilograms) per second. If so, the victim at its prime would have had a minimum diameter of about 3 miles (5 kilometers).
All the evidence suggested that WD 1647+375 was snacking at an object that was once an icy planetesimal floating around the local version of the Kuiper Belt, an icy ring of debris around our solar system.
A peek into the past and future
This discovery offers a surprising window into both the past and future of cosmic systems, the researchers explained.
For instance, comets and icy planetesimals like WD 1647+375’s giant snack “deliver water and other volatiles to terrestrial planets in extrasolar systems—a prerequisite for the development of life in other worlds,” according to the paper. Now that we know such icy planetesimals do exist, this theory could be tested further with other objects, namely the recent interstellar comet visitor, 3I/ATLAS.
But WD 1647+375 itself offers a sneak peek of what’s to come for our own solar system, Sahu added. Our Sun will eventually burn out and collapse into a white dwarf like WD 1647+375. When that happens, the planets in our solar system may encounter a similar fate as this icy planetesimal.
“If an alien observer looks into our solar system in the far future,” Sahu said, “they might see the same kind of remains we see today around this white dwarf.”
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![Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics](https://gizmodo.com/app/uploads/2026/06/East-Antarctic-Fan-shaped-Basin-Province.jpeg)
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