Astronomers spot two white dwarfs doomed to die in a quadruple detonation
By Will Dunham
WASHINGTON (Reuters) -Astronomers have spotted two hefty white dwarf stars - highly compact stellar embers - orbiting close together that appear destined to die in an extraordinarily violent quadruple detonation.
The two stars, gravitationally bound to each other in what is called a binary system, are located in our Milky Way galaxy about 160 light-years from Earth - relatively close in cosmic terms. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).
White dwarfs are among the most compact celestial objects. Stars with up to eight times the mass of our sun appear destined to end up this way. They eventually burn up all the hydrogen they use as fuel. Gravity then causes them to collapse and blow off their outer layers in a "red giant" stage, eventually leaving behind a compact core roughly the diameter of Earth - the white dwarf.
"White dwarfs are the stellar remnants of the vast majority of stars, and from time to time we find systems where two white dwarfs closely orbit each other," said James Munday, a PhD researcher at the University of Warwick in England and lead author of the study published in the journal Nature Astronomy.
The researchers used data from four ground-based telescopes to study this binary system. One of the white dwarfs has a mass about 83% that of our sun and the other about 72%. No other known white dwarf binary has a larger combined mass, Munday said.
"They are both about as big as the Earth. One has a diameter about 20% larger and the other about 50% larger. That gives you an idea of how dense they are. It's the sun compressed onto the size of Earth. Their masses when they were regular stars were probably around three to four times the mass of the sun," said University of Warwick astrophysicist and study co-author Ingrid Pelisoli.
A few hundred binary systems composed of two white dwarf stars are known. These two orbit closest to each other of any of them. They are about 25 times closer to each other than our solar system's innermost planet Mercury is to the sun, completing an orbit every roughly 14 hours.
With the gap between them very gradually narrowing as the binary system loses energy, the fact that they are so massive and so close ensures their demise over a large timescale.
When they get closer to each other, the heavier of the two white dwarfs, because of its greater gravitational strength, will begin to draw material from the lighter one's outer layer and increase in mass past the threshold beyond which a white dwarf experiences a thermonuclear explosion.
This will set the stage for a complex explosion called a type 1a supernova, in this instance involving a quadruple detonation.
"White dwarfs are made up of layers, much like an onion. Their inner layer is a core of carbon and oxygen, surrounded by a helium layer and finally by a hydrogen layer," Pelisoli said.
"The less-massive star will transfer mass to the massive one when they start interacting. This will lead the helium layer (of the heavier one) to become too massive, triggering an explosion. This then triggers a second explosion in the carbon-oxygen core. The shock wave from these explosions in turn triggers a third explosion in the remaining helium layer of the companion, which triggers a fourth explosion in its carbon-oxygen core," Pelisoli added.
This quadruple detonation is expected to take about four seconds, start to finish. But it will not come anytime soon.
The researchers calculate that it will occur approximately 22.6 billion years from now. The universe is about 13.8 billion years old. When the explosion occurs, it would appear from the perspective of Earth about 10 times brighter than the moon in the night sky - if Earth, now about 4.5 billion years old, still exists.
This is the first time a binary system apparently headed for such a fate has been identified. If the two white dwarfs were far enough apart that the heavier one would not siphon material from the lighter one, they could survive in perpetual peace.
"In a wider orbit, they could indeed live stably without any catastrophic future, but here we know that the explosion will light up our side of the galaxy," Munday said.
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
5 hours ago
- Yahoo
What are rare earth elements and why are they important?
STORY: EDITORS NOTE: THIS SCRIPT AND VIDEO HAVE BEEN REFILED DUE TO A U.S.-CHINA TRADE DEAL BEING REACHED WITH A FRAMEWORK TO REMOVE CHINESE EXPORT RESTRICTIONS ON RARE EARTH MINERALS. THE STORY WAS FIRST PUBLISHED ON FEBRUARY 28, 2025. Rare earth minerals are used in almost every technology you can think of. They're present in cellphones, medical devices, wind turbines, weapons and much more. But what are they? And why are they important? And are they actually rare? :: What are rare earths and why are they important? :: Julie Michelle Klinger, Geographer 'So the term rare earth elements, it refers to 17 chemically similar elements within the Lanthanide series.' This is Professor Julie Michelle Klinger, a geographer and senior visiting fellow at the Institute for Human Sciences. 'So, if you can picture the periodic table, it's that bar at the bottom. Elements 57 to 71 plus scandium and yttrium.' Reuters' special correspondent on commodities, Eric Onstad, has a bit of the history. :: Eric Onstad, Specialist Correspondent, Commodities, Reuters 'The elements were first discovered by a Swedish miner in 1787 near a village called Ytterby and that's reflected in the name of two rare earths, yttrium and ytterbium. Another rare earth, promethium, was named by the wife of one of the discoverers after the Greek god who stole fire from the gods and gave it to humans. China is by far the dominant producer. They account for 60% of mine production and 90% of processed rare earths. But interestingly, this wasn't always the case. In the 1980s, for instance, the United States was the biggest producer and Europe had one of the biggest processing plants in the world.' :: What are they used for? KLINGER: 'They are often described as the vitamins or the spice of industry because they have enabled our technologies to get smaller and faster and stronger and more resilient.' Elements like lanthanum and cerium, some of the most common rare earths, are used in TVs and lighting... While the application of erbium and yttrium can range from nuclear power to lasers. ONSTAD: 'There are two broad categories that have really got the spotlight. The first one is military uses, and that can be from night goggles, to precision missiles, to radar. And of course, that is a very sensitive issue for nations wanting to guard their access to those kinds of minerals. The second area is regarding the energy transition. And there are four specific rare earths that are used to make super-strong permanent magnets that are used in motors for electric vehicle and for wind turbines. So that is key for most nations' zero-carbon targets and cutting greenhouse gases.' :: What is the environmental impact of extraction? KLINGER: 'It's really because of the challenges, the heavy energy and resource and pollution risks that are associated with refining rare earth elements, that production has concentrated historically in so few places.' Processing rare earths often involves the use of solvents, which can produce toxic waste. More environmentally friendly technologies are being developed, but they are not yet widely used. ONSTAD: 'The other issue is that some rare earth deposits are radioactive. They include uranium and thorium. And so, some countries are not interested in having that be mined in their country.' :: Are they actually rare? But are they actually rare? Not really... ONSTAD: 'They are found all over the world. And in terms of the deposits, no, they are not actually rare. What's rare about them is sometimes they are found in very small quantities. And in addition to that, they're mixed with all kinds of other minerals. So, the difficulty is sometimes extracting each single rare earth from all the other minerals that are involved in the deposit. "
New York Post
6 hours ago
- New York Post
Doctors warn against ‘dangerous' viral Chinese sleep hack: ‘A physics experiment on your spinal cord'
It's not that kind of swingers party. How far would you go to get a good night's rest? Would you take supplements, journal or do a fire-burning ritual? How about swinging from your neck in a public park? That's precisely what some senior citizens in the northern Chinese city of Shenyang are doing — and it's going viral. 6 People in China are swinging from their necks in public parks to get better sleep. Future Publishing via Getty Images Footage shared on social media shows older adults looping U‑shaped belts attached to playground bars or trees around their chins and gently swaying back and forth like lemurs, seemingly without a care in the world. While it's certainly not a sight you wanna stumble across in the middle of the night, locals swear by this bizarre practice as a cure for sleep-related issues and spinal discomfort. The brains behind this operation is Sun Rongchun, 57, who developed the device to treat his cervical spondylosis — a common, age-related condition that can cause headaches, dizziness and insomnia, the Economic Times reported. Rongchun has trademarked the device and applied to have it patented — until then, he comes to the park every day to educate the public. 6 Footage shared on social media shows older adults looping U‑shaped belts attached to playground bars or trees around their chins and gently swaying back and forth like lemurs. REUTERS It seems his spinal exercises are really taking off. 'In the past, my cervical spine was in bad shape, so I was uncomfortable lying down every night, but after a few days, it worked pretty well,' one fan told local media. 'Now, my throat condition is better and the uncomfortable symptoms are completely gone. I've been doing this exercise for two years already.' 6 Sun Rongchun, 57, developed the device to treat his cervical spondylosis. Future Publishing via Getty Images It's unclear exactly how this device works on the spine — and experts say this is one trick you definitely should not be trying at home. 'People are desperate for better sleep, but no trend is worth risking paralysis or stroke,' said certified sleep science coach Rosie Osmun of 'Hanging any part of your body, let alone your neck, is biomechanically dangerous. There are safe, research-backed alternatives that actually work.' 6 'In the past, my cervical spine was in bad shape, so I was uncomfortable lying down every night, but after a few days, it worked pretty well,' one participant said. Future Publishing via Getty Images Done wrong, this trend can result in nerve damage, spinal injury or even death from restricted blood flow to the brain. There's already been at least one reported incident in which a man died after mistakenly looping the belt around his neck instead of his chin. 6 'Hanging any part of your body, let alone your neck, is biomechanically dangerous,' one expert said. REUTERS Human error aside, in a public park, you've also got the elements to contend with. 'Medical traction uses precise grams of force; park-belt swinging is essentially an uncontrolled physics experiment on your spinal cord,' said physical therapist Dr. Jennifer Miller, who is affiliated with Amerisleep. According to Osmun, the only reason these sleeping hacks gain traction is because 'they're dramatic, visually striking and falsely promise quick fixes for chronic problems.' 6 There's already been at least one reported incident in which a man died after mistakenly looping the belt around his neck instead of his chin. REUTERS If you're looking for a soothing, rocking sensation to make you feel like a baby before bed — get a hammock. Otherwise, you might be in for the forever sleep. 'Sleep is essential for life, but so is safety,' Osmun said. 'The solution isn't in belts, but in balance: real strategies grounded in science, not spectacle.'
Yahoo
10 hours ago
- Yahoo
Solar Orbiter spacecraft obtains first images of the sun's poles
By Will Dunham (Reuters) -The robotic Solar Orbiter spacecraft has obtained the first images ever taken of our sun's two poles as scientists seek a deeper understanding of Earth's host star, including its magnetic field, its 11-year cycle of activity and the solar wind. The European Space Agency on Wednesday released images taken in March using three of Solar Orbiter's onboard instruments. They show the sun's south pole from a distance of roughly 40 million miles (65 million km), obtained at a period of maximum solar activity. Images of the north pole are still being transmitted by the spacecraft back to Earth. Solar Orbiter, developed by ESA in collaboration with the U.S. space agency NASA, was launched in 2020 from Florida. Until now, all the views of the sun have come from the same vantage point - looking face-on toward its equator from the plane on which Earth and most of the solar system's other planets orbit, called the ecliptic plane. Solar Orbiter used a slingshot flyby around Venus in February to get out of this plane to view the sun from up to 17 degrees below the solar equator. Future slingshot flybys will provide an even better view, at beyond 30 degrees. "The best is still to come. What we have seen is just a first quick peek," said solar physicist Sami Solanki of the Max Planck Institute for Solar System Research in Germany, who heads the scientific team for the spacecraft's Polarimetric and Helioseismic Imager instrument. "The spacecraft observed both poles, first the south pole, then the north pole," Solanki said. "The north pole's data will arrive in the coming weeks or months." Solar Orbiter is gathering data on phenomena including the sun's magnetic field, its activity cycle, and the solar wind, a relentless high-speed flow of charged particles emanating from the sun's outermost atmospheric layer that fills interplanetary space. "We are not sure what we will find, and it is likely we will see things that we didn't know about before," said solar physicist Hamish Reid of University College London's Mullard Space Science Laboratory, UK co-principal investigator of Solar Orbiter's Extreme Ultraviolet Imager instrument. The sun is a ball of hot electrically charged gas that, as it moves, generates a powerful magnetic field, which flips from south to north and back again every 11 years in what is called the solar cycle. The magnetic field drives the formation of sunspots, cooler regions on the solar surface that appear as dark blotches. At the cycle's beginning, the sun has fewer sunspots. Their number increases as the cycle progresses, before starting all over again. "What we have been missing to really understand this (solar cycle) is what is actually happening at the top and bottom of the sun," Reid said. The sun's diameter is about 865,000 miles (1.4 million km), more than 100 times wider than Earth. "Whilst the Earth has a clear north and south pole, the Solar Orbiter measurements show both north and south polarity magnetic fields are currently present at the south pole of the sun. This happens during the maximum in activity of the solar cycle, when the sun's magnetic field is about to flip. In the coming years, the sun will reach solar minimum, and we expect to see a more orderly magnetic field around the poles of the sun," Reid said. "We see in the images and movies of the polar regions that the sun's magnetic field is chaotic at the poles at the (current) phase of the solar cycle - high solar activity, cycle maximum," Solanki said. The sun is located about 93 million miles (149 million km) from our planet. "The data that Solar Orbiter obtains during the coming years will help modelers in predicting the solar cycle. This is important for us on Earth because the sun's activity causes solar flares and coronal mass ejections which can result in radio communication blackouts, destabilize our power grids, but also drive the sensational auroras," Reid said. "Solar Orbiter's new vantage point out of the ecliptic will also allow us to get a better picture of how the solar wind expands to form the heliosphere, a vast bubble around the sun and its planets," Reid added. A previous spacecraft, Ulysses, flew over the solar poles in the 1990s. "Ulysses, however, was blind in the sense that it did not carry any optical instruments - telescopes or cameras - and hence could only sense the solar wind passing the spacecraft directly, but could not image the sun," Solanki said.
