Latest news with #Yusef-Zadeh
Yahoo
23-02-2025
- Science
- Yahoo
Scientists Turn James Webb to Examine Black Hole at Center of Our Galaxy and Saw Something Wild
The James Webb Space Telescope has peered 13 billion years in the past and tens of billions of light-years away from our planet. And in a recent experiment, scientists decided to look deep into a black hole that's way closer to home — where they were met with an explosive light show. As CNN reports, scientists at Northwestern University turned the groundbreaking space telescope onto Sagittarius A*, the central black hole at the heart of our Milky Way Galaxy that's about 26,000 light-years away from Earth, to see what its sensitive instruments would pick up. In the most detailed look at that black hole ever undertaken, the astrophysicists observed incredible flares of light spewing out of Sagittarius A* that CNN described as resembling pyrotechnics. As the researchers explained in a new paper published in The Astrophysical Journal Letters, these types of flares usually burst out of accretion disks, or swirling disks of hot gas and dust. Though they're not completely sure of its origin, the scientists behind this discovery say they think it came from an accretion disk located just beyond the black hole's event horizon — a region with gravity so dense that even light can't escape. "In our data, we saw constantly changing, bubbling brightness," Farhad Yusef-Zadeh, a physics and astronomy professor at Northwestern who was the study's lead author, told CNN. "And then boom! A big burst of brightness suddenly popped up. Then, it calmed down again." As Yusef-Zadeh acknowledges, these fantastic flares appear to be happening at random. "We couldn't find a pattern in this activity," he said. "The activity profile of this black hole was new and exciting every time that we looked at it." Though they're effectively invisible, astronomers are able to "see" black holes because of their effect on the things around them. Anything that wanders too close to one gets sucked into its gravitational pull. Any dust and gas that gets pulled in starts to swirl super-fast in that maelstrom, forming accretion disks that heat up as they "feed" the black hole. While the mechanism that fuels black holes is pretty well understood, astrophysicists don't know exactly why these galaxy-powering bodies emit these bright, energetic flares. According to Yusef-Zadeh, the flares witnessed in Sagittarius A* are singular even for such mysterious motions. "Flares are expected to happen in essentially all supermassive black holes, but our black hole is unique," he explained. "It is always bubbling with activity and never seems to reach a steady state." Over a period of a year, the researchers watched Saggitarius A* in eight-to-ten-hour increments. During that time, as Yusef-Zadeh explained, "we noticed changes in every observation." "We saw something different each time," the scientist told CNN, "which is really remarkable." More on James Webb discoveries: Scientists Surprised to Realize Red Dots in James Webb Images Are Black Holes
Yahoo
20-02-2025
- Science
- Yahoo
Webb Catches Mysterious Light Flares Around Milky Way's Supermassive Black Hole
Between spotting galaxies that shouldn't exist, capturing the interstellar medium with unprecedented clarity, and identifying new worlds, the James Webb Space Telescope is a busy observatory. But as it orbits the Sun, Webb has kept a close eye on one of the most obscure pieces of our galaxy: Sagittarius A*, the supermassive black hole at the center of the Milky Way. By capturing the longest and most detailed Sag A* observations yet, Webb has allowed astronomers to catch a constant light show around the black hole's accretion disk, which draws in Sag A*'s cosmic meals. In a study published Tuesday in The Astrophysical Journal Letters, an international team of researchers from several space science organizations shared that Webb's NIRCam (Near-InfraRed Camera) spotted many pops of light near Sag A* across 48 hours of observation. These flashes, which varied in strength, appeared to flare from the inner edge of the black hole's accretion disk. Flares aren't unusual near supermassive black holes, so on its own, the identification of light flares around Sag A* wouldn't have been particularly exciting. What was odd about the team's findings was that Sag A*'s light show never appeared to stop, even as the team studied the flashes over seven 8-to-10-hour observation periods between 2023 and 2024. The only variables they noticed were in wavelength and length of time—data that, thanks to NIRCam's dual modules, could be captured simultaneously during a single session. "Flares are expected to happen in essentially all supermassive black holes, but our black hole is unique," said astrophysicist and lead study author Farhad Yusef-Zadeh in a Northwestern University statement. "It is always bubbling with activity and never seems to reach a steady state. We observed the black hole multiple times…and we noticed changes in every observation. We saw something different each time, which is really remarkable. Nothing ever stayed the same." Yusef-Zadeh and his colleagues believe the flares could be the product of the same phenomenon that produces sporadic flashes near other black holes: feisty accretion disks. These swirling disks of gas and dust gravitationally pull matter toward the black hole, eventually tipping that material past the point of no return (the black hole's event horizon). This steady stream of snacks allows the black hole to grow in mass. Every now and then, turbulence within the accretion disk squeezes the disk's plasma, triggering a quick burst of radiation. "It's similar to how the Sun's magnetic field gathers, compresses, and then erupts a solar flare," Yusef-Zadeh told NASA. "Of course, the processes are more dramatic because the environment around a black hole is much more energetic and much more extreme. But the Sun's surface also bubbles with activity." But an even more powerful force could be behind Sag A*'s larger flares. When two magnetic fields collide in space, they release energy in the form of accelerated particles. These particles travel so fast that they emit bright bursts of radiation, according to NASA. If "magnetic reconnection events" are happening in Sag A*'s accretion disk, that could explain the more aggressive pops of light. In the future, the researchers hope to use Webb's NIRCam to observe Sag A* for 24 hours straight. Only a long, uninterrupted period like this would allow the team to see whether the accretion disk's light show is based on any particular pattern or is truly random.
Yahoo
19-02-2025
- Science
- Yahoo
Astronomers spot flares of light near the black hole at the center of our galaxy
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Astronomers using the James Webb Space Telescope have spied dynamic flares of light near the supermassive black hole at the center of the Milky Way galaxy. The constant, rapid-fire display includes seconds-long short flashes and longer, blindingly bright flares of light on a daily basis. The Webb observations mark the longest, most detailed look researchers have been able to make around the Milky Way's central black hole, called Sagittarius A*, building on past evidence of its highly energetic activity. While black holes are invisible, the flares unleashed by the swirling disk of hot gas and dust, or accretion disk, that orbits Sagittarius A* resemble a pyrotechnic extravaganza. A study describing the findings was published Tuesday in The Astrophysical Journal Letters. Astronomers believe the flares are coming from the inner edge of the accretion disk just beyond the black hole's event horizon, or the area around a black hole where the pull of gravity is so strong that not even light can escape, according to NASA. 'In our data, we saw constantly changing, bubbling brightness,' said lead study author Farhad Yusef-Zadeh, a professor of physics and astronomy at Northwestern University's Weinberg College of Arts and Sciences, in a statement. 'And then boom! A big burst of brightness suddenly popped up. Then, it calmed down again. We couldn't find a pattern in this activity. It appears to be random. The activity profile of this black hole was new and exciting every time that we looked at it.' The observations could shed light on how black holes behave and the ways they feed on their surroundings. The strong, gravitational influence of black holes pulls in gas and dust from any celestial object that wanders too close. The gas and dust swirl together at high speeds, forming the accretion disk that feeds the black hole. The rapid movement of the material causes it to heat up, releasing energy in the form of radiation as well as jets of material that don't make it into the black hole. The radiation and jets can change the way gas is distributed throughout galaxies and feed the formation of stars, which is why supermassive black holes are regarded as giant engines at the centers of galaxies. Yusef-Zadeh and his colleagues observed Sagittarius A*, also called Sgr A*, for 48 hours over the course of one year in eight to 10-hour increments, using Webb's Near-Infrared Camera to track the black hole's activity. The team spied five to six big flares a day as well as smaller flashes of light in between. 'Flares are expected to happen in essentially all supermassive black holes, but our black hole is unique,' Yusef-Zadeh said. 'It is always bubbling with activity and never seems to reach a steady state. We observed the black hole multiple times throughout 2023 and 2024, and we noticed changes in every observation. We saw something different each time, which is really remarkable.' The variability of the black hole's activity is likely due to the random nature of the material flowing into the accretion disk, Yusef-Zadeh said. The team believes the short bursts of light are created by minor, turbulent fluctuations within the accretion disk that could squeeze hot, energetic gas called plasma and cause a flash of radiation. 'It's similar to how the Sun's magnetic field gathers together, compresses, and then erupts a solar flare,' Yusef-Zadeh said in a statement. 'Of course, the processes are more dramatic because the environment around a black hole is much more energetic and much more extreme.' Meanwhile, the longer, bigger flares may occur due to magnetic reconnection events, or when two different magnetic fields collide near the black hole and release energetic particles moving near the speed of light. 'A magnetic reconnection event is like a spark of static electricity, which, in a sense, also is an 'electric reconnection,'' Yusef-Zadeh said. Webb's capabilities enabled the team to observe the black hole's flaring across two different wavelengths of light simultaneously. '(It was like) seeing the world in color versus in black and white, and (we) found rainbows,' Yusef-Zadeh said. 'This tells you about the nature of flaring activity and the physical characteristics of the radiation mechanism, the magnetic field and the density of flares more directly.' The observations provide a deeper look at how the black hole's activity varies in brightness over time, said Tuan Do, associate professor in the physics and astronomy department and deputy director of the Galactic Center Group at UCLA. Do was not involved in this study but has led research on Sagittarius A* in the past, including when the black hole showcased unusual activity in 2019. 'Sgr A* got about half as bright in the new data as was seen in 2019, so I think that 2019 is still unusually active for the black hole,' Do said. 'The black hole and its environment (are) always changing though so we are never sure what we'll find! This is what makes observations of the galactic center so exciting, even though we've stared at this spot in the sky for decades now.' When the authors of the latest study observed the two different wavelengths of light from the black hole simultaneously, they realized the shorter wavelength changed in brightness just before the longer wavelength. The observation suggested that as the particles spiral around magnetic field lines, they lose energy more quickly. The changes in brightness have been noted in previous research and recent complementary data from the Mid-Infrared Instrument on the Webb telescope and other observatories. 'I think the next big step would be to try to connect these different data sources together to form a fuller picture of the physics of the environment around the supermassive black hole,' Do said. The new study also confirms the black hole has 'non-stop variability,' as previously observed, said Mark Morris, distinguished research professor in the department of physics and astronomy at UCLA. Morris was not involved in the new study. 'X-ray astronomers see reasonably strong evidence that in the last few hundred years, there has been at least one, maybe two instances of enormous flares taking place,' Morris said via email, 'with intensities (10,000 to 100,000) times larger than anything we've seen in the last quarter century that we have been closely examining Sgr A*.' What might have caused these flares? Astronomers still don't know, but it's possible the black hole gobbled up a planet a few hundred years ago, Morris said. When the sun releases solar storms, scientists worry because such activity can potentially affect GPS, communications and the power grid on Earth. But at 25,000 light-years away, the highly energetic and variable activity of the Milky Way's central black hole isn't a concern, Morris said. However, the Webb telescope observations allow researchers to understand what kind of 'storms' are created when matter is compressed and heated as it is drawn toward the black hole. 'Beyond pure interest in the most dazzling fireworks that the universe can produce, those fireworks can have a profound effect on the evolution of the galaxies that they are in,' Morris said. 'They can provoke or impede star formation on large scales, they can remove gas and clear out galaxies, leaving them unable to form stars.' The study authors don't believe the black hole was experiencing an unusual spike in activity, but they want to observe Sagittarius A* for an uninterrupted 24 hours to be sure. 'We also can see if these flares show periodicity (or repeat themselves) or if they are truly random,' Yusef-Zadeh said. Astronomers still don't know how fast Sagittarius A* is spinning as it gobbles up matter, but longer observations could provide the data necessary to find the answer. Ultimately, more data from Webb observations of Sagittarius A* could help astronomers simulate how accretion disks behave around black holes, as well as comparing the behaviors of less energetically active, black holes with more active ones.
CNN
19-02-2025
- Science
- CNN
Webb telescope spies the Milky Way's black hole constantly ‘bubbling' with light
Astronomers using the James Webb Space Telescope have spied dynamic flares of light near the supermassive black hole at the center of the Milky Way galaxy. The constant, rapid-fire display includes seconds-long short flashes and longer, blindingly bright flares of light on a daily basis. The Webb observations mark the longest, most detailed look researchers have been able to make around the Milky Way's central black hole, called Sagittarius A*, building on past evidence of its highly energetic activity. While black holes are invisible, the flares unleashed by the swirling disk of hot gas and dust, or accretion disk, that orbits Sagittarius A* resemble a pyrotechnic extravaganza. A study describing the findings was published Tuesday in The Astrophysical Journal Letters. Astronomers believe the flares are coming from the inner edge of the accretion disk just beyond the black hole's event horizon, or the area around a black hole where the pull of gravity is so strong that not even light can escape, according to NASA. 'In our data, we saw constantly changing, bubbling brightness,' said lead study author Farhad Yusef-Zadeh, a professor of physics and astronomy at Northwestern University's Weinberg College of Arts and Sciences, in a statement. 'And then boom! A big burst of brightness suddenly popped up. Then, it calmed down again. We couldn't find a pattern in this activity. It appears to be random. The activity profile of this black hole was new and exciting every time that we looked at it.' The observations could shed light on how black holes behave and the ways they feed on their surroundings. Watching celestial fireworks The strong, gravitational influence of black holes pulls in gas and dust from any celestial object that wanders too close. The gas and dust swirl together at high speeds, forming the accretion disk that feeds the black hole. The rapid movement of the material causes it to heat up, releasing energy in the form of radiation as well as jets of material that don't make it into the black hole. The radiation and jets can change the way gas is distributed throughout galaxies and feed the formation of stars, which is why supermassive black holes are regarded as giant engines at the centers of galaxies. Yusef-Zadeh and his colleagues observed Sagittarius A*, also called Sgr A*, for 48 hours over the course of one year in eight to 10-hour increments, using Webb's Near-Infrared Camera to track the black hole's activity. The team spied five to six big flares a day as well as smaller flashes of light in between. 'Flares are expected to happen in essentially all supermassive black holes, but our black hole is unique,' Yusef-Zadeh said. 'It is always bubbling with activity and never seems to reach a steady state. We observed the black hole multiple times throughout 2023 and 2024, and we noticed changes in every observation. We saw something different each time, which is really remarkable.' The variability of the black hole's activity is likely due to the random nature of the material flowing into the accretion disk, Yusef-Zadeh said. The team believes the short bursts of light are created by minor, turbulent fluctuations within the accretion disk that could squeeze hot, energetic gas called plasma and cause a flash of radiation. 'It's similar to how the Sun's magnetic field gathers together, compresses, and then erupts a solar flare,' Yusef-Zadeh said in a statement. 'Of course, the processes are more dramatic because the environment around a black hole is much more energetic and much more extreme.' Meanwhile, the longer, bigger flares may occur due to magnetic reconnection events, or when two different magnetic fields collide near the black hole and release energetic particles moving near the speed of light. 'A magnetic reconnection event is like a spark of static electricity, which, in a sense, also is an 'electric reconnection,'' Yusef-Zadeh said. A 'rainbow' of activity Webb's capabilities enabled the team to observe the black hole's flaring across two different wavelengths of light simultaneously. '(It was like) seeing the world in color versus in black and white, and (we) found rainbows,' Yusef-Zadeh said. 'This tells you about the nature of flaring activity and the physical characteristics of the radiation mechanism, the magnetic field and the density of flares more directly.' The observations provide a deeper look at how the black hole's activity varies in brightness over time, said Tuan Do, associate professor in the physics and astronomy department and deputy director of the Galactic Center Group at UCLA. Do was not involved in this study but has led research on Sagittarius A* in the past, including when the black hole showcased unusual activity in 2019. 'Sgr A* got about half as bright in the new data as was seen in 2019, so I think that 2019 is still unusually active for the black hole,' Do said. 'The black hole and its environment (are) always changing though so we are never sure what we'll find! This is what makes observations of the galactic center so exciting, even though we've stared at this spot in the sky for decades now.' When the authors of the latest study observed the two different wavelengths of light from the black hole simultaneously, they realized the shorter wavelength changed in brightness just before the longer wavelength. The observation suggested that as the particles spiral around magnetic field lines, they lose energy more quickly. The changes in brightness have been noted in previous research and recent complementary data from the Mid-Infrared Instrument on the Webb telescope and other observatories. 'I think the next big step would be to try to connect these different data sources together to form a fuller picture of the physics of the environment around the supermassive black hole,' Do said. The new study also confirms the black hole has 'non-stop variability,' as previously observed, said Mark Morris, distinguished research professor in the department of physics and astronomy at UCLA. Morris was not involved in the new study. 'X-ray astronomers see reasonably strong evidence that in the last few hundred years, there has been at least one, maybe two instances of enormous flares taking place,' Morris said via email, 'with intensities (10,000 to 100,000) times larger than anything we've seen in the last quarter century that we have been closely examining Sgr A*.' What might have caused these flares? Astronomers still don't know, but it's possible the black hole gobbled up a planet a few hundred years ago, Morris said. When the sun releases solar storms, scientists worry because such activity can potentially affect GPS, communications and the power grid on Earth. But at 25,000 light-years away, the highly energetic and variable activity of the Milky Way's central black hole isn't a concern, Morris said. However, the Webb telescope observations allow researchers to understand what kind of 'storms' are created when matter is compressed and heated as it is drawn toward the black hole. 'Beyond pure interest in the most dazzling fireworks that the universe can produce, those fireworks can have a profound effect on the evolution of the galaxies that they are in,' Morris said. 'They can provoke or impede star formation on large scales, they can remove gas and clear out galaxies, leaving them unable to form stars.' A longer look The study authors don't believe the black hole was experiencing an unusual spike in activity, but they want to observe Sagittarius A* for an uninterrupted 24 hours to be sure. 'We also can see if these flares show periodicity (or repeat themselves) or if they are truly random,' Yusef-Zadeh said. Astronomers still don't know how fast Sagittarius A* is spinning as it gobbles up matter, but longer observations could provide the data necessary to find the answer. Ultimately, more data from Webb observations of Sagittarius A* could help astronomers simulate how accretion disks behave around black holes, as well as comparing the behaviors of less energetically active, black holes with more active ones.
CNN
19-02-2025
- Science
- CNN
Webb telescope spies the Milky Way's black hole constantly ‘bubbling' with light
Astronomers using the James Webb Space Telescope have spied dynamic flares of light near the supermassive black hole at the center of the Milky Way galaxy. The constant, rapid-fire display includes seconds-long short flashes and longer, blindingly bright flares of light on a daily basis. The Webb observations mark the longest, most detailed look researchers have been able to make around the Milky Way's central black hole, called Sagittarius A*, building on past evidence of its highly energetic activity. While black holes are invisible, the flares unleashed by the swirling disk of hot gas and dust, or accretion disk, that orbits Sagittarius A* resemble a pyrotechnic extravaganza. A study describing the findings was published Tuesday in The Astrophysical Journal Letters. Astronomers believe the flares are coming from the inner edge of the accretion disk just beyond the black hole's event horizon, or the area around a black hole where the pull of gravity is so strong that not even light can escape, according to NASA. 'In our data, we saw constantly changing, bubbling brightness,' said lead study author Farhad Yusef-Zadeh, a professor of physics and astronomy at Northwestern University's Weinberg College of Arts and Sciences, in a statement. 'And then boom! A big burst of brightness suddenly popped up. Then, it calmed down again. We couldn't find a pattern in this activity. It appears to be random. The activity profile of this black hole was new and exciting every time that we looked at it.' The observations could shed light on how black holes behave and the ways they feed on their surroundings. Watching celestial fireworks The strong, gravitational influence of black holes pulls in gas and dust from any celestial object that wanders too close. The gas and dust swirl together at high speeds, forming the accretion disk that feeds the black hole. The rapid movement of the material causes it to heat up, releasing energy in the form of radiation as well as jets of material that don't make it into the black hole. The radiation and jets can change the way gas is distributed throughout galaxies and feed the formation of stars, which is why supermassive black holes are regarded as giant engines at the centers of galaxies. Yusef-Zadeh and his colleagues observed Sagittarius A*, also called Sgr A*, for 48 hours over the course of one year in eight to 10-hour increments, using Webb's Near-Infrared Camera to track the black hole's activity. The team spied five to six big flares a day as well as smaller flashes of light in between. 'Flares are expected to happen in essentially all supermassive black holes, but our black hole is unique,' Yusef-Zadeh said. 'It is always bubbling with activity and never seems to reach a steady state. We observed the black hole multiple times throughout 2023 and 2024, and we noticed changes in every observation. We saw something different each time, which is really remarkable.' The variability of the black hole's activity is likely due to the random nature of the material flowing into the accretion disk, Yusef-Zadeh said. The team believes the short bursts of light are created by minor, turbulent fluctuations within the accretion disk that could squeeze hot, energetic gas called plasma and cause a flash of radiation. 'It's similar to how the Sun's magnetic field gathers together, compresses, and then erupts a solar flare,' Yusef-Zadeh said in a statement. 'Of course, the processes are more dramatic because the environment around a black hole is much more energetic and much more extreme.' Meanwhile, the longer, bigger flares may occur due to magnetic reconnection events, or when two different magnetic fields collide near the black hole and release energetic particles moving near the speed of light. 'A magnetic reconnection event is like a spark of static electricity, which, in a sense, also is an 'electric reconnection,'' Yusef-Zadeh said. A 'rainbow' of activity Webb's capabilities enabled the team to observe the black hole's flaring across two different wavelengths of light simultaneously. '(It was like) seeing the world in color versus in black and white, and (we) found rainbows,' Yusef-Zadeh said. 'This tells you about the nature of flaring activity and the physical characteristics of the radiation mechanism, the magnetic field and the density of flares more directly.' The observations provide a deeper look at how the black hole's activity varies in brightness over time, said Tuan Do, associate professor in the physics and astronomy department and deputy director of the Galactic Center Group at UCLA. Do was not involved in this study but has led research on Sagittarius A* in the past, including when the black hole showcased unusual activity in 2019. 'Sgr A* got about half as bright in the new data as was seen in 2019, so I think that 2019 is still unusually active for the black hole,' Do said. 'The black hole and its environment (are) always changing though so we are never sure what we'll find! This is what makes observations of the galactic center so exciting, even though we've stared at this spot in the sky for decades now.' When the authors of the latest study observed the two different wavelengths of light from the black hole simultaneously, they realized the shorter wavelength changed in brightness just before the longer wavelength. The observation suggested that as the particles spiral around magnetic field lines, they lose energy more quickly. The changes in brightness have been noted in previous research and recent complementary data from the Mid-Infrared Instrument on the Webb telescope and other observatories. 'I think the next big step would be to try to connect these different data sources together to form a fuller picture of the physics of the environment around the supermassive black hole,' Do said. The new study also confirms the black hole has 'non-stop variability,' as previously observed, said Mark Morris, distinguished research professor in the department of physics and astronomy at UCLA. Morris was not involved in the new study. 'X-ray astronomers see reasonably strong evidence that in the last few hundred years, there has been at least one, maybe two instances of enormous flares taking place,' Morris said via email, 'with intensities (10,000 to 100,000) times larger than anything we've seen in the last quarter century that we have been closely examining Sgr A*.' What might have caused these flares? Astronomers still don't know, but it's possible the black hole gobbled up a planet a few hundred years ago, Morris said. When the sun releases solar storms, scientists worry because such activity can potentially affect GPS, communications and the power grid on Earth. But at 25,000 light-years away, the highly energetic and variable activity of the Milky Way's central black hole isn't a concern, Morris said. However, the Webb telescope observations allow researchers to understand what kind of 'storms' are created when matter is compressed and heated as it is drawn toward the black hole. 'Beyond pure interest in the most dazzling fireworks that the universe can produce, those fireworks can have a profound effect on the evolution of the galaxies that they are in,' Morris said. 'They can provoke or impede star formation on large scales, they can remove gas and clear out galaxies, leaving them unable to form stars.' A longer look The study authors don't believe the black hole was experiencing an unusual spike in activity, but they want to observe Sagittarius A* for an uninterrupted 24 hours to be sure. 'We also can see if these flares show periodicity (or repeat themselves) or if they are truly random,' Yusef-Zadeh said. Astronomers still don't know how fast Sagittarius A* is spinning as it gobbles up matter, but longer observations could provide the data necessary to find the answer. Ultimately, more data from Webb observations of Sagittarius A* could help astronomers simulate how accretion disks behave around black holes, as well as comparing the behaviors of less energetically active, black holes with more active ones.
