Latest news with #ZitengWang
Yahoo
05-06-2025
- Science
- Yahoo
Something Deep in Our Galaxy Is Pulsing Every 44 Minutes. No One Knows Why.
Here's what you'll learn when you read this story: ASKAP J1832-0911 is a long-period radio transient (LPT) object, which emits radio waves in periods of tens of minutes. But it is also the first LPT known to emit X-rays. This mysterious object could take many forms, including a pulsar, a white dwarf star in a binary with a low-mass star, or a magnetar. The object's properties don't exactly fit with any of those proposed options, however. Deep in the galactic plane of the Milky Way, within a region of stars shrouded in gas and dust, one star is behaving like no other that has ever been observed before. Stars can be as mysterious as they are mesmerizing. When scientists at NASA's Chandra X-Ray Observatory were making observations with the Advanced CCD Imaging Spectrometer (ACIS) X-ray imaging instrument, something bizarre appeared—a previously unidentified source of X-rays. Intense X-ray and radio pulses were coming from this source, which is known as ASKAP J1832-0911. This extreme object is a long-period radio transient, or LPT—an astrophysical object whose brightness keeps changing. Few long-period radio transients, whose radio wave emissions vary over tens of minutes, are known. In fact, the first one was only spotted in 2022. The radio wave intensity of ASKAP J1832-0911 cycled every 44 minutes, and was exceptionally bright in radio at the time of observation. Most excitingly for scientists, LPTs had never before been observed emitting both X-rays and radio waves. Astronomer Ziteng Wang from Curtin University in Australia—who led the team of researchers investigating ASKAP J1832-0911—wanted to find out more. The object was observed six months later with ACIS and the Follow-Up Telescope on board ESA's Einstein Probe. By then, its X-ray luminosity had decreased, and so had its radio emissions. But its existence alone is a breakthrough in itself. 'ASKAP J1832–0911 is currently the only LPT detected with (pulsed) X-ray emission — perhaps unsurprisingly, given its extreme radio brightness and the potential correlation between the radio and X-ray luminosities,' Wang and his team said in a study recently published in Nature. This object is thought to be some sort of star, but exactly what kind of star remains debatable. The researchers believe ASKAP J1832–0911 to be compact and to have strong magnetic fields, which would align with the properties of either a magnetic white dwarf (the corpse of a star that has lost its outer layers of gas) or a pulsar (a rotating neutron star that is highly magnetized). But then, there is the issue of its unprecedented pulses. Its X-ray pulses alone are too variable to line up with the steady flash of a pulsar, and X-ray emissions from white dwarves also tend to be fainter and more stable than those produced by ASKAP J1832–0911. So, if it isn't a pulsar or white dwarf, then what is it? Well, it might be a binary white dwarf system—fast-spinning white dwarfs are sometimes found locked in binary systems with other low-mass stars. The radio emissions from these binaries are usually significantly weaker than those from ASKAP J1832–0911, but Wang suggests that the situation remains possible. If not a binary white dwarf system, however, ASKAP J1832–0911 could be a magnetar. These isolated neutron stars have powerful magnetic fields, and the mystery object's properties (including varied pulses and a radio spectrum that is constantly changing)are in line with those of magnetars that emit strong radio waves. Magnetars also throw 'tantrums' with similar X-ray outbursts. But ASKAP J1832–0911 also differs from the typical presentation of magnetars—its quiescent X-ray luminosity (the opposite of its peak luminosity) doesn't line up with expected magnetar behavior, and its especially low luminosity when its rotation slows down doesn't match either. Older magentars are thought to act more like this, but cannot reach such bright radio extremes as ASKAP J1832–0911. 'It could host an unusual core-dominated magnetic field […] requiring a revision to models of magnetic field evolution in neutron stars,' Wang said. 'If ASKAP J1832–0911 is an old magnetar, explaining the radio emission challenges existent models.' Whatever ASKAP J1832–0911 actually is, classifying it will demand consideration of the strength and frequency of both X-ray and radio emissions. For now, it just winks at us. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Yahoo
30-05-2025
- General
- Yahoo
Scientists Are Stumped by Mysterious Pulsing 'Star'
ASKAP J1832 (in circle) captured by th Chandra X-Ray Observatory Credit - X-ray: NASA/CXC/ICRAR, Curtin Univ./Z. Wang et al.; Infrared: NASA/JPL/CalTech/IPAC; Radio: SARAO/MeerKAT; Image processing: NASA/CXC/SAO/N. Wolk Something strange is going on 15,000 light years from Earth. Out at that distant remove, somewhere in the constellation Scutum, an unexplained body is semaphoring into space, blinking in both X-ray and radio frequencies once every 44 minutes in a way never seen by astronomers before. The object could be a white dwarf—an Earth-sized husk that remains after a star has exhausted its nuclear fuel. Or not. It could also be a magnetar—a neutron star with an exceedingly powerful magnetic field. Unless it's not that either. 'Astronomers have looked at countless stars with all kinds of telescopes and we've never seen one that acts this way,' said astronomer Ziteng Wang of Curtin University in Australia, in a statement that accompanied the May 28 release of a paper in Nature describing the object, for which he was lead author. 'It's thrilling to see a new type of behavior for stars.' So what exactly is the mysterious body—which goes by the technical handle ASKAP J1832—and how common is this species of object? ASKAP J1832 is by no means unique in the universe in sending out energy in steady flashes. Pulsars—rapidly spinning neutron stars—do too. But pulsars flash much faster than ASKAP J1832 does, on the order of milliseconds to seconds. In 2022, astronomers discovered a type of object known as a long-period transient, which, like ASKAP J1832, sends out flashes of radio waves on the order of tens of minutes. So far 10 such bodies have been found, but none identical to ASKAP J1832, which is the first to emit X-rays too. What's more, ASKAP J1832's emissions have changed over time. During one observation with NASA's orbiting Chandra X-Ray Observatory in February 2024, the object was prodigiously producing both X-rays and radio waves. During a follow-up observation six months later, the radio waves were 1,000 times fainter and no X-rays were detected. That was a puzzle. 'We looked at several different possibilities involving neutron stars and white dwarfs, either in isolation or with companion stars,' said co-author Nanda Rea of the Institute of Space Sciences in Barcelona, Spain, in a statement. 'So far nothing exactly matches up, but some ideas work better than others.' One of those ideas is the magnetar, but that doesn't fit precisely, due to ASKAP J1832's bright and variable radio emissions. The white dwarf remains a possibility, however in order to produce the amount of energy it does, ASKAP J1832 would have to be orbiting another body in a formation known as a binary system, and so far that second body hasn't been detected. Viewed from Earth, ASKAP J1832 appears to be located in a supernova remnant, a cloud of hot gas and high energy particles that remains after an aging star meets its explosive end. But the authors of the paper concluded that the remnant merely lies in the foreground of the observational field with ASKAP J1832 in the background, the way an earthly cloud can drift in the path of the sun. So for now, the object remains a riddle—one that will be investigated further. 'Finding a mystery like this isn't frustrating,' said co-author Tong Bao of the Italian National Institute for Astrophysics, in a statement. 'It's what makes science exciting.' Write to Jeffrey Kluger at
Time Magazine
30-05-2025
- Science
- Time Magazine
Scientists Are Stumped by Mysterious Pulsing ‘Star'
Something strange is going on 15,000 light years from Earth. Out at that distant remove, somewhere in the constellation Scutum, an unexplained body is semaphoring into space, blinking in both X-ray and radio frequencies once every 44 minutes in a way never seen by astronomers before. The object could be a white dwarf —an Earth-sized husk that remains after a star has exhausted its nuclear fuel. Or not. It could also be a magnetar —a neutron star with an exceedingly powerful magnetic field. Unless it's not that either. 'Astronomers have looked at countless stars with all kinds of telescopes and we've never seen one that acts this way,' said astronomer Ziteng Wang of Curtin University in Australia, in a statement that accompanied the May 28 release of a paper in Nature describing the object, for which he was lead author. 'It's thrilling to see a new type of behavior for stars.' So what exactly is the mysterious body—which goes by the technical handle ASKAP J1832—and how common is this species of object? ASKAP J1832 is by no means unique in the universe in sending out energy in steady flashes. Pulsars —rapidly spinning neutron stars—do too. But pulsars flash much faster than ASKAP J1832 does, on the order of milliseconds to seconds. In 2022, astronomers discovered a type of object known as a long-period transient, which, like ASKAP J1832, sends out flashes of radio waves on the order of tens of minutes. So far 10 such bodies have been found, but none identical to ASKAP J1832, which is the first to emit X-rays too. What's more, ASKAP J1832's emissions have changed over time. During one observation with NASA's orbiting Chandra X-Ray Observatory in February 2024, the object was prodigiously producing both X-rays and radio waves. During a follow-up observation six months later, the radio waves were 1,000 times fainter and no X-rays were detected. That was a puzzle. 'We looked at several different possibilities involving neutron stars and white dwarfs, either in isolation or with companion stars,' said co-author Nanda Rea of the Institute of Space Sciences in Barcelona, Spain, in a statement. 'So far nothing exactly matches up, but some ideas work better than others.' One of those ideas is the magnetar, but that doesn't fit precisely, due to ASKAP J1832's bright and variable radio emissions. The white dwarf remains a possibility, however in order to produce the amount of energy it does, ASKAP J1832 would have to be orbiting another body in a formation known as a binary system, and so far that second body hasn't been detected. Viewed from Earth, ASKAP J1832 appears to be located in a supernova remnant, a cloud of hot gas and high energy particles that remains after an aging star meets its explosive end. But the authors of the paper concluded that the remnant merely lies in the foreground of the observational field with ASKAP J1832 in the background, the way an earthly cloud can drift in the path of the sun. So for now, the object remains a riddle—one that will be investigated further. 'Finding a mystery like this isn't frustrating,' said co-author Tong Bao of the Italian National Institute for Astrophysics, in a statement. 'It's what makes science exciting.'
Malay Mail
30-05-2025
- General
- Malay Mail
Astronomers discover mysterious star emitting rare combination of X-rays and radio waves
WASHINGTON, May 31 — Astronomers have spotted a star acting unlike any other ever observed as it unleashes a curious combination of radio waves and X-rays, pegging it as an exotic member of a class of celestial objects first identified only three years ago. It is located in the Milky Way galaxy about 15,000 light-years from Earth in the direction of the constellation Scutum, flashing every 44 minutes in both radio waves and X-ray emissions. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). The researchers said it belongs to a class of objects called 'long-period radio transients,' known for bright bursts of radio waves that appear every few minutes to several hours. This is much longer than the rapid pulses in radio waves typically detected from pulsars - a type of speedily rotating neutron star, the dense collapsed core of a massive star after its death. Pulsars appear, as viewed from Earth, to be blinking on and off on timescales of milliseconds to seconds. 'What these objects are and how they generate their unusual signals remain a mystery,' said astronomer Ziteng Wang of Curtin University in Australia, lead author of the study published this week in the journal Nature. In the new study, the researchers used data from Nasa's orbiting Chandra X-ray Observatory, the ASKAP telescope in Australia and other telescopes. While the emission of radio waves from the newly identified object is similar to the approximately 10 other known examples of this class, it is the only one sending out X-rays, according to astrophysicist and study co-author Nanda Rea of the Institute of Space Sciences in Barcelona. The researchers have some hypotheses about the nature of this star. They said it may be a magnetar, a spinning neutron star with an extreme magnetic field, or perhaps a white dwarf, a highly compact stellar ember, with a close and quick orbit around a small companion star in what is called a binary system. 'However, neither of them could explain all observational features we saw,' Wang said. Stars with up to eight times the mass of our sun appear destined to end up as a white dwarf. 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. The observed radio waves potentially could have been generated by the interaction between the white dwarf and the hypothesized companion star, the researchers said. 'The radio brightness of the object varies a lot. We saw no radio emission from the object before November 2023. And in February 2024, we saw it became extremely bright. 'Fewer than 30 objects in the sky have ever reached such brightness in radio waves. Remarkably, at the same time, we also detected X-ray pulses from the object. We can still detect it in radio, but much fainter,' Wang said. Wang said it is thrilling to see a new type of behavior for stars. 'The X-ray detection came from NASA's Chandra space telescope. That part was a lucky break. The telescope was actually pointing at something else, but just happened to catch the source during its 'crazy' bright phase. A coincidence like that is really, really rare - like finding a needle in a haystack,' Wang said. — Reuters
The Advertiser
29-05-2025
- Science
- The Advertiser
Astronomers scrutinise a star behaving unlike any other
Astronomers have spotted a star acting unlike any other ever observed as it unleashes a curious combination of radio waves and X-rays. It is located in the Milky Way galaxy about 15,000 light-years from Earth in the direction of the constellation Scutum, flashing every 44 minutes in both radio waves and X-ray emissions. A light-year is the distance light travels in a year, 9.5 trillion kilometres. The researchers said it belongs to a class of objects called "long-period radio transients," known for bright bursts of radio waves that appear every few minutes to several hours. This is much longer than the rapid pulses in radio waves typically detected from pulsars - a type of speedily rotating neutron star, the dense collapsed core of a massive star after its death. Pulsars appear, as viewed from Earth, to be blinking on and off on timescales of milliseconds to seconds. "What these objects are and how they generate their unusual signals remain a mystery," said astronomer Ziteng Wang of Perth's Curtin University, lead author of the study published this week in the journal Nature. In the new study, the researchers used data from NASA's orbiting Chandra X-ray Observatory, the ASKAP telescope in Australia and other telescopes. While the emission of radio waves from the newly identified object is similar to the approximately 10 other known examples of this class, it is the only one sending out X-rays, according to astrophysicist and study co-author Nanda Rea of the Institute of Space Sciences in Barcelona. The researchers have some hypotheses about the nature of this star. They said it may be a magnetar, a spinning neutron star with an extreme magnetic field, or perhaps a white dwarf, a highly compact stellar ember, with a close and quick orbit around a small companion star in what is called a binary system. "However, neither of them could explain all observational features we saw," Wang said. Stars with up to eight times the mass of our sun appear destined to end up as a white dwarf. 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. The observed radio waves potentially could have been generated by the interaction between the white dwarf and the hypothesised companion star, the researchers said. "The radio brightness of the object varies a lot. We saw no radio emission from the object before November 2023. And in February 2024, we saw it became extremely bright. Fewer than 30 objects in the sky have ever reached such brightness in radio waves. Remarkably, at the same time, we also detected X-ray pulses from the object. We can still detect it in radio, but much fainter," Wang said. Wang said it is thrilling to see a new type of behaviour for stars. "The X-ray detection came from NASA's Chandra space telescope. That part was a lucky break. The telescope was actually pointing at something else, but just happened to catch the source during its crazy bright phase. A coincidence like that is really, really rare - like finding a needle in a haystack," Wang said. Astronomers have spotted a star acting unlike any other ever observed as it unleashes a curious combination of radio waves and X-rays. It is located in the Milky Way galaxy about 15,000 light-years from Earth in the direction of the constellation Scutum, flashing every 44 minutes in both radio waves and X-ray emissions. A light-year is the distance light travels in a year, 9.5 trillion kilometres. The researchers said it belongs to a class of objects called "long-period radio transients," known for bright bursts of radio waves that appear every few minutes to several hours. This is much longer than the rapid pulses in radio waves typically detected from pulsars - a type of speedily rotating neutron star, the dense collapsed core of a massive star after its death. Pulsars appear, as viewed from Earth, to be blinking on and off on timescales of milliseconds to seconds. "What these objects are and how they generate their unusual signals remain a mystery," said astronomer Ziteng Wang of Perth's Curtin University, lead author of the study published this week in the journal Nature. In the new study, the researchers used data from NASA's orbiting Chandra X-ray Observatory, the ASKAP telescope in Australia and other telescopes. While the emission of radio waves from the newly identified object is similar to the approximately 10 other known examples of this class, it is the only one sending out X-rays, according to astrophysicist and study co-author Nanda Rea of the Institute of Space Sciences in Barcelona. The researchers have some hypotheses about the nature of this star. They said it may be a magnetar, a spinning neutron star with an extreme magnetic field, or perhaps a white dwarf, a highly compact stellar ember, with a close and quick orbit around a small companion star in what is called a binary system. "However, neither of them could explain all observational features we saw," Wang said. Stars with up to eight times the mass of our sun appear destined to end up as a white dwarf. 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. The observed radio waves potentially could have been generated by the interaction between the white dwarf and the hypothesised companion star, the researchers said. "The radio brightness of the object varies a lot. We saw no radio emission from the object before November 2023. And in February 2024, we saw it became extremely bright. Fewer than 30 objects in the sky have ever reached such brightness in radio waves. Remarkably, at the same time, we also detected X-ray pulses from the object. We can still detect it in radio, but much fainter," Wang said. Wang said it is thrilling to see a new type of behaviour for stars. "The X-ray detection came from NASA's Chandra space telescope. That part was a lucky break. The telescope was actually pointing at something else, but just happened to catch the source during its crazy bright phase. A coincidence like that is really, really rare - like finding a needle in a haystack," Wang said. Astronomers have spotted a star acting unlike any other ever observed as it unleashes a curious combination of radio waves and X-rays. It is located in the Milky Way galaxy about 15,000 light-years from Earth in the direction of the constellation Scutum, flashing every 44 minutes in both radio waves and X-ray emissions. A light-year is the distance light travels in a year, 9.5 trillion kilometres. The researchers said it belongs to a class of objects called "long-period radio transients," known for bright bursts of radio waves that appear every few minutes to several hours. This is much longer than the rapid pulses in radio waves typically detected from pulsars - a type of speedily rotating neutron star, the dense collapsed core of a massive star after its death. Pulsars appear, as viewed from Earth, to be blinking on and off on timescales of milliseconds to seconds. "What these objects are and how they generate their unusual signals remain a mystery," said astronomer Ziteng Wang of Perth's Curtin University, lead author of the study published this week in the journal Nature. In the new study, the researchers used data from NASA's orbiting Chandra X-ray Observatory, the ASKAP telescope in Australia and other telescopes. While the emission of radio waves from the newly identified object is similar to the approximately 10 other known examples of this class, it is the only one sending out X-rays, according to astrophysicist and study co-author Nanda Rea of the Institute of Space Sciences in Barcelona. The researchers have some hypotheses about the nature of this star. They said it may be a magnetar, a spinning neutron star with an extreme magnetic field, or perhaps a white dwarf, a highly compact stellar ember, with a close and quick orbit around a small companion star in what is called a binary system. "However, neither of them could explain all observational features we saw," Wang said. Stars with up to eight times the mass of our sun appear destined to end up as a white dwarf. 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. The observed radio waves potentially could have been generated by the interaction between the white dwarf and the hypothesised companion star, the researchers said. "The radio brightness of the object varies a lot. We saw no radio emission from the object before November 2023. And in February 2024, we saw it became extremely bright. Fewer than 30 objects in the sky have ever reached such brightness in radio waves. Remarkably, at the same time, we also detected X-ray pulses from the object. We can still detect it in radio, but much fainter," Wang said. Wang said it is thrilling to see a new type of behaviour for stars. "The X-ray detection came from NASA's Chandra space telescope. That part was a lucky break. The telescope was actually pointing at something else, but just happened to catch the source during its crazy bright phase. A coincidence like that is really, really rare - like finding a needle in a haystack," Wang said. Astronomers have spotted a star acting unlike any other ever observed as it unleashes a curious combination of radio waves and X-rays. It is located in the Milky Way galaxy about 15,000 light-years from Earth in the direction of the constellation Scutum, flashing every 44 minutes in both radio waves and X-ray emissions. A light-year is the distance light travels in a year, 9.5 trillion kilometres. The researchers said it belongs to a class of objects called "long-period radio transients," known for bright bursts of radio waves that appear every few minutes to several hours. This is much longer than the rapid pulses in radio waves typically detected from pulsars - a type of speedily rotating neutron star, the dense collapsed core of a massive star after its death. Pulsars appear, as viewed from Earth, to be blinking on and off on timescales of milliseconds to seconds. "What these objects are and how they generate their unusual signals remain a mystery," said astronomer Ziteng Wang of Perth's Curtin University, lead author of the study published this week in the journal Nature. In the new study, the researchers used data from NASA's orbiting Chandra X-ray Observatory, the ASKAP telescope in Australia and other telescopes. While the emission of radio waves from the newly identified object is similar to the approximately 10 other known examples of this class, it is the only one sending out X-rays, according to astrophysicist and study co-author Nanda Rea of the Institute of Space Sciences in Barcelona. The researchers have some hypotheses about the nature of this star. They said it may be a magnetar, a spinning neutron star with an extreme magnetic field, or perhaps a white dwarf, a highly compact stellar ember, with a close and quick orbit around a small companion star in what is called a binary system. "However, neither of them could explain all observational features we saw," Wang said. Stars with up to eight times the mass of our sun appear destined to end up as a white dwarf. 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. The observed radio waves potentially could have been generated by the interaction between the white dwarf and the hypothesised companion star, the researchers said. "The radio brightness of the object varies a lot. We saw no radio emission from the object before November 2023. And in February 2024, we saw it became extremely bright. Fewer than 30 objects in the sky have ever reached such brightness in radio waves. Remarkably, at the same time, we also detected X-ray pulses from the object. We can still detect it in radio, but much fainter," Wang said. Wang said it is thrilling to see a new type of behaviour for stars. "The X-ray detection came from NASA's Chandra space telescope. That part was a lucky break. The telescope was actually pointing at something else, but just happened to catch the source during its crazy bright phase. A coincidence like that is really, really rare - like finding a needle in a haystack," Wang said.
