Latest news with #LPTs
Indian Express
3 days ago
- Science
- Indian Express
Scientists baffled by unknown space object that emits X-ray and radio waves every 44 minutes
Scientists have discovered a strange object in space, which they say behaves 'like no other seen before.' Located in the Milky Way, around 15,000 light years away from Earth, the mysterious object ASKAP J1832-0911 is sending pulses of radio waves and X-rays for two minutes straight every 44 minutes. First discovered by NASA's Chandra X-ray Observatory, ASKAP J1832-0911 belongs to a class of objects called 'long period radio transients' (also known as LPT), which emit intense radio waves over tens of minutes. NASA says that these waves are thousands of times longer than the length of repeated variations seen in pulsars, which are rapidly spinning neutron stars. According to team leader and Curtin University researcher Zieng (Andy) Wang, 'Discovering that ASKAP J1832-0911 was emitting X-rays felt like finding a needle in a haystack. The ASKAP radio telescope has a wide field view of the night sky, while Chandra observes only a fraction of it. So, it was fortunate that Chandra observed the same area of the night sky at the same time.' Discovered in 2022, LPTs are cosmic bodies that emit radio pulses every few minutes or hours. In the last few years, astronomers have come across 10 LPTs, but say that ASKAP J1832-0911 is unlike any other. Using Chandra, scientists have discovered that ASKAP J1832-0911 also emits 'regularly varying' X-rays every 44 minutes, making it the first long-period radio transient object to do so. As of now, there is no explanation as to how or why LPTs generate these signals and why they 'switch on' and 'switch off' at long, regular and irregular intervals. However, researchers believe that ASKAP J1832-0911 is a dead star, but don't know what type it is. Some say that it could be a magnetar, which is the core of a dead star, while others assume that it could be a pair of stars where one of the two is a highly magnetised dwarf.
Scientific American
5 days ago
- Science
- Scientific American
Astronomers Discover Mysterious Object Bursting with X-Rays
3 min read A celestial object some 15,000 light-years away is emitting bright flashes of radio and X-rays that scientists are struggling to explain By & One of the strangest cosmic objects ever seen just got even weirder — NASA's Chandra X-ray telescope caught it blasting out X-ray radiation and radio waves. The mystery object, known as ASKAP J1832- 0911, is located within the Milky Way about 15,000 light-years away from Earth. It's now known to flash in both radio waves and X-rays for a two-minute period every 44 minutes. This is the first time an object like this, a so-called "long-period transient" or "LPT," has been seen in high-energy X-ray light as well as low-energy radio wave light. The team behind this discovery hopes the finding could help reveal what these flashing objects actually are and how they launch their mystery signals. On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. However, not only is there no explanation for how the signals from LPTs are generated yet, but astronomers also don't know why these signals "switch on" and "switch off" at long, regular and unusual intervals. "This object is unlike anything we have seen before," team leader and Curtin University researcher Zieng (Andy) Wang said in a statement. Chandra gets lucky. Star doesn't. LPTs are flashing cosmic bodies that emit radio pulses separated by a few minutes or a few hours. They were first discovered in 2022, making them a very recent discovery. Since this initial detection, astronomers from around the globe have discovered a further 10 LPTs. None seem to be quite like this one, though — not yet anyway. ASKAP J1832- 0911 was first spotted by astronomers using the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope in Wajarri Country, Australia. The team then followed this initial LPT discovery in radio waves with further investigation using NASA's Chandra X-ray telescope, shockingly finding that its highly periodic and unusual radio emissions are mimicked in X-rays. In fact, catching ASKAP J1832- 0911 throwing its regular X-ray tantrum was a matter of good fortune. "Discovering that ASKAP J1832-0911 was emitting X-rays felt like finding a needle in a haystack," Wang said. "The ASKAP radio telescope has a wide field view of the night sky, while Chandra observes only a fraction of it. So, it was fortunate that Chandra observed the same area of the night sky at the same time." The team believes the true nature of ASKAP J1832-0911 is a dead star, they just don't quite know what form that star takes. A highly magnetic neutron star, or " magnetar," is one option, and a a white dwarf — the kind of stellar remnant the sun will leave behind when it dies in over 5 billion years — is another. 'ASKAP J1831- 0911 could be a magnetar, the core of a dead star with powerful magnetic fields, or it could be a pair of stars in a binary system where one of the two is a highly magnetized white dwarf, a low-mass star at the end of its evolution," Wang said. "However, even those theories do not fully explain what we are observing. "This discovery could indicate a new type of physics or new models of stellar evolution." The hope is the discovery that at least one LPT emits X-rays in the same way it does radio waves could help shed light on the mysterious origins of these objects. That's because the fact that X-rays are so much more energetic than radio waves are means whatever the object behind ASKAP J1832- 0911 is, it must be able to produce both types of radiation. That should narrow down the field of suspects — and, there should be more LPTs out there acting just like this one, the study team reasons. "Finding one such object hints at the existence of many more," Nanda Rea, study team member and a researcher at the Institute of Space Science (ICE-CSIC) and Catalan Institute for Space studies (IEEC), said in the statement. "The discovery of its transient X-ray emission opens fresh insights into their mysterious nature." The team's research was published on Wednesday (May 28) in the journal Nature.
ABC News
6 days ago
- General
- ABC News
Strange flashing object discovered in deep space puzzles astronomers
In the past few years, astronomers have recorded a handful of very strange radio signals, mostly coming from towards the centre of the Milky Way. Armed with increasingly powerful telescopes, they've detected objects that emit powerful bursts of energy a few times an hour, like a chiming clock — and then fall silent. The source of these "long-period radio transients", or LPTs, hasn't been nailed down, but it was thought they were caused by dead stars. But a newly discovered LPT, reported in the journal Nature, could shift our view about the origin of these mysterious objects. Unlike previous discoveries, this LPT also sends out X-ray pulses, making it the strangest one yet. An international team, led by Curtin University astronomer Ziteng Andy Wang, first detected a radio signal in data captured by the Australian Square Kilometre Array Pathfinder telescope (ASKAP) in Western Australia. Dubbed ASKAP J1832-0911, the object sent out radio waves for two minutes every 44 minutes. By chance the signal was also spotted by NASA's Chandra X-ray Observatory on Valentine's Day last year. Dr Wang said he was "pretty surprised" when he saw pulses of X-rays happening at the same time as the radio waves. "That is a huge discovery," Dr Wang said. The X-ray and radio pulses were emitted for a few weeks, and then fell silent. Had Chandra not been observing that patch of sky, the X-ray bursts would never have been detected. Astronomers have known about flashing objects since the 1960s, but until a few years ago, each one that had been recorded flickered very quickly, switching on and off every few seconds or minutes. Then, in 2022, an Australian-led team discovered an LPT which emitted super-bright radio waves regularly over hours. A handful of other LPTs have been discovered since. Researchers have proposed different theories for the source of these LPTs. One is a super-dense star called a neutron star that spins, regularly hitting Earth with a beam of energy from its poles. But these stars were thought to only be detectable when they were spinning very quickly, becoming too faint to see as they slowed down to LPT-level speeds. Or they could be weaker dead stars — white dwarfs — in binary systems, interacting with other stars. Michael Cowley, an astronomer at Queensland University of Technology who wasn't involved with the new research, pointed out a pre-print study from last year which supported this second theory. "This seemed like a reasonable answer and a promising step toward solving the puzzle," Dr Cowley said. But he said the detection of X-rays coming from ASKAP J1832-0911 "throws a spanner in the works". "Pulsed X-rays are usually associated with rotating neutron stars," Dr Cowley said. He believed this meant that LPTs could be coming from several different sources. "My takeaway is that LPTs don't appear to be a single phenomenon. Instead, they may represent a new category of objects, defined not by a shared origin but by how they behave." Dr Wang said it wasn't clear whether the new observation could be a white dwarf or a neutron star. "Both are possible, but personally I would prefer an isolated neutron star," he said. Whichever it is, the object has an extremely strong magnetic field, several billion times that of the Earth. This makes them very difficult to learn more about, according Stuart Ryder, an astronomer at Macquarie University who also wasn't involved with the research. "They're such extreme states of matter, we don't really have a good understanding of them because we can't replicate that here on Earth," Dr Ryder said. But the sheer weirdness of the object presents other opportunities. As radio telescopes improve, and more LPTs are discovered, they may help physicists understand how matter works in strange environments. "If we can study extra-strong magnetic fields in objects and elsewhere in the Universe, then we can learn a lot about the physics of matter," Dr Ryder said. He believes that understanding this extreme magnetism could help nudge science closer to clean nuclear fusion energy on Earth. "At the end of the day, a star is basically just a natural form of a fusion reactor, and we're trying to replicate those conditions in a very controlled manner here on Earth."
