Latest news with #MonthlyNoticesof
Yahoo
08-07-2025
- Science
- Yahoo
Astronomers discover ‘fossil galaxy' 3 billion light-years away
A galaxy that has remained unchanged for 7 billion years — a rarity in the universe — has been observed by astronomers, offering a glimpse into cosmic history and adding to an enigmatic collection of objects called relics or 'fossil galaxies.' These space oddities are galaxies that, after an initial phase of intense star formation, escape their expected evolutionary path. While other galaxies expand and merge with one another, the fossil galaxies remain virtually inactive. Like celestial time capsules, they provide a snapshot into the ancient universe and allow astronomers to examine the mechanism of galaxy formation. The newly discovered fossil galaxy — named KiDS J0842+0059 — is about 3 billion light-years from Earth, making it both the most distant and the first of its kind observed outside the local universe, the region of space closest to Earth that is approximately 1 billion light-years in radius. It was found by a team of astronomers led by the Italian National Institute for Astrophysics (INAF), using high-resolution imaging from the Large Binocular Telescope in Arizona. 'Relic galaxies, just by chance, did not merge with any other galaxy, remaining more or less intact through time,' said Crescenzo Tortora, a researcher at INAF and first author of a study on the finding published May 31 in the journal Monthly Notices of the Royal Astronomical Society. 'These objects are very rare because, as time goes on, the probability to merge with another galaxy naturally increases.' Astronomers believe that the most massive galaxies form in two phases, according to study coauthor Chiara Spiniello, a researcher at the University of Oxford in the UK. 'First, there's an early burst of star formation, a very quick and violent activity,' she said. 'We end up having something very compact and small, the progenitor of this relic.' The second phase, she added, is a protracted process during which galaxies that are in close proximity start interacting, merging and eating each other, causing a very dramatic change in their shapes, sizes and star populations. 'We define a relic as an object that missed almost completely this second phase, having formed at least 75% of its mass in the first phase,' Spiniello explained. The telltale feature of fossil galaxies is that they are very old, compact and dense, much more so than our own galaxy. 'They contain (billions) of stars as massive as the sun and they are not forming any new stars — they're doing essentially nothing, and they are the fossil records of the very ancient universe,' she said. 'They formed when the universe was really, really young. And then, for some reasons that we honestly don't understand yet, they did not interact. They didn't merge with other systems. They evolved undisturbed, and they remained as they were.' Fossil galaxies are crucial because they are a direct link to the massive galaxy population that existed billions of years ago, said Michele Cappellari, a professor of astrophysics at the University of Oxford who was not involved with the study. 'As 'living fossils,' they have avoided the chaotic mergers and growth that most other massive galaxies have experienced. Studying them allows us to reconstruct the conditions of the universe in its infancy and understand the initial bursts of star formation,' he said. What caused these galaxies to stop forming stars so abruptly is a major question, he added. 'Evidence from both local and (distant) observations suggests that feedback from supermassive black holes may be responsible,' Cappellari said. 'These black holes can produce powerful winds that expel or heat the gas in a galaxy, preventing further star formation. However, this remains an active area of research.' Scientists initially identified KiDS J0842+0059 in 2018 using the VLT Survey Telescope (VST) at the Paranal Observatory in Chile. That observation revealed that the galaxy was populated by very old stars but only provided an estimate of its mass and size, so a more detailed observation was required to confirm it was a relic. The Large Binocular Telescope used for this confirmation can render very sharp images due to its ability to compensate for atmospheric turbulence, which otherwise can make it difficult for Earth-based telescopes to focus on distant objects. The newly found fossil galaxy joins a group of only a handful of others that have been observed at the same level of detail, the most pristine of which — called NGC 1277 — was confirmed by the Hubble Space Telescope in 2018. NGC 1277 and KiDS J0842+0059 are very similar, but the latter is much farther away from Earth. It fits the definition of fossil galaxy almost perfectly, according to Spiniello. 'This is what we call an extreme relic,' she said, 'because almost all, or 99.5% of its stars were formed incredibly early on in cosmic time, and the galaxy did absolutely nothing thereafter.' The fossil galaxy has stars and planets, just like our own galaxy, but it is much more dense, Spiniello added. 'There will be many more stars in a tiny, tiny volume, so it'll be super crowded,' she said. 'And it will be much harder to find solar systems like ours, with many planets orbiting around it, just because of the chances of getting companion stars interfering nearby.' KiDS J0842+0059 looks to observers like it did 3 billion years ago, because that's how long it takes for the light coming from the galaxy to reach Earth. Spiniello hypothesized that the relic will likely remain as it is forever, but scientists can't be certain since they still don't know what keeps it from interacting with other galaxies. 'There must be something that prevents them from merging, but without knowing what, we cannot really predict what's going to happen in the future,' Spiniello said. It is very hard to identify fossil galaxies and confirm their nature, partly because they're relatively rare and small compared with regular galaxies such as the Milky Way, according to Sébastien Comerón, an extragalactic astronomer at the Universidad de La Laguna and the Instituto de Astrofísica de Canarias in Spain. The confirmation of a distant relic galaxy is a credit to the search strategies used to identify these objects and of modern instruments, he said. 'Relic galaxies are mysterious,' added Comerón, who was not involved with the study, in an email. 'The fact that a few galaxies are nowadays untouched relics of the first large galaxies needs an explanation.' Astronomers can't say for certain how rare relics are, but Spiniello estimates there might be 'one in millions' among all the galaxies in the universe. The INSPIRE project — which aims to find and catalogue fossil galaxies and spawned the discovery of KiDS J0842+0059 — has already identified several dozen other candidates that are in the pipeline for further scrutiny, Spiniello said. New instruments could make this search even more effective. Both Spiniello and Tortora are excited about Euclid, a European Space Agency telescope launched in 2023 with the goal of exploring dark matter and dark energy that will also be useful for observing fossil galaxies. 'Euclid will be transformational,' Spiniello said, 'because rather than observing one single object at a time, its wide sky survey configuration will cover a lot more. The idea is to find all the galaxies in a patch of sky, and then isolate all the ones that are ultra compact. And if you do that, then you can actually estimate how rare (fossil galaxies) are.' Confirming relic galaxy KiDS J0842+0059 at such a distance is a remarkable achievement, and the future of this field is very promising, Cappellari said in an email. 'With powerful new telescopes like James Webb and Euclid (which produced its first images just a few months ago), and on the ground with advanced adaptive optics, we can expect to find and study more of these relics at even greater distances.'
CNN
08-07-2025
- Science
- CNN
Astronomers discover ‘fossil galaxy' 3 billion light-years away
A galaxy that has remained unchanged for 7 billion years — a rarity in the universe — has been observed by astronomers, offering a glimpse into cosmic history and adding to an enigmatic collection of objects called relics or 'fossil galaxies.' These space oddities are galaxies that, after an initial phase of intense star formation, escape their expected evolutionary path. While other galaxies expand and merge with one another, the fossil galaxies remain virtually inactive. Like celestial time capsules, they provide a snapshot into the ancient universe and allow astronomers to examine the mechanism of galaxy formation. The newly discovered fossil galaxy — named KiDS J0842+0059 — is about 3 billion light-years from Earth, making it both the most distant and the first of its kind observed outside the local universe, the region of space closest to Earth that is approximately 1 billion light-years in radius. It was found by a team of astronomers led by the Italian National Institute for Astrophysics (INAF), using high-resolution imaging from the Large Binocular Telescope in Arizona. 'Relic galaxies, just by chance, did not merge with any other galaxy, remaining more or less intact through time,' said Crescenzo Tortora, a researcher at INAF and first author of a study on the finding published May 31 in the journal Monthly Notices of the Royal Astronomical Society. 'These objects are very rare because, as time goes on, the probability to merge with another galaxy naturally increases.' Astronomers believe that the most massive galaxies form in two phases, according to study coauthor Chiara Spiniello, a researcher at the University of Oxford in the UK. 'First, there's an early burst of star formation, a very quick and violent activity,' she said. 'We end up having something very compact and small, the progenitor of this relic.' The second phase, she added, is a protracted process during which galaxies that are in close proximity start interacting, merging and eating each other, causing a very dramatic change in their shapes, sizes and star populations. 'We define a relic as an object that missed almost completely this second phase, having formed at least 75% of its mass in the first phase,' Spiniello explained. The telltale feature of fossil galaxies is that they are very old, compact and dense, much more so than our own galaxy. 'They contain (billions) of stars as massive as the sun and they are not forming any new stars — they're doing essentially nothing, and they are the fossil records of the very ancient universe,' she said. 'They formed when the universe was really, really young. And then, for some reasons that we honestly don't understand yet, they did not interact. They didn't merge with other systems. They evolved undisturbed, and they remained as they were.' Fossil galaxies are crucial because they are a direct link to the massive galaxy population that existed billions of years ago, said Michele Cappellari, a professor of astrophysics at the University of Oxford who was not involved with the study. 'As 'living fossils,' they have avoided the chaotic mergers and growth that most other massive galaxies have experienced. Studying them allows us to reconstruct the conditions of the universe in its infancy and understand the initial bursts of star formation,' he said. What caused these galaxies to stop forming stars so abruptly is a major question, he added. 'Evidence from both local and (distant) observations suggests that feedback from supermassive black holes may be responsible,' Cappellari said. 'These black holes can produce powerful winds that expel or heat the gas in a galaxy, preventing further star formation. However, this remains an active area of research.' Scientists initially identified KiDS J0842+0059 in 2018 using the VLT Survey Telescope (VST) at the Paranal Observatory in Chile. That observation revealed that the galaxy was populated by very old stars but only provided an estimate of its mass and size, so a more detailed observation was required to confirm it was a relic. The Large Binocular Telescope used for this confirmation can render very sharp images due to its ability to compensate for atmospheric turbulence, which otherwise can make it difficult for Earth-based telescopes to focus on distant objects. The newly found fossil galaxy joins a group of only a handful of others that have been observed at the same level of detail, the most pristine of which — called NGC 1277 — was confirmed by the Hubble Space Telescope in 2018. NGC 1277 and KiDS J0842+0059 are very similar, but the latter is much farther away from Earth. It fits the definition of fossil galaxy almost perfectly, according to Spiniello. 'This is what we call an extreme relic,' she said, 'because almost all, or 99.5% of its stars were formed incredibly early on in cosmic time, and the galaxy did absolutely nothing thereafter.' The fossil galaxy has stars and planets, just like our own galaxy, but it is much more dense, Spiniello added. 'There will be many more stars in a tiny, tiny volume, so it'll be super crowded,' she said. 'And it will be much harder to find solar systems like ours, with many planets orbiting around it, just because of the chances of getting companion stars interfering nearby.' KiDS J0842+0059 looks to observers like it did 3 billion years ago, because that's how long it takes for the light coming from the galaxy to reach Earth. Spiniello hypothesized that the relic will likely remain as it is forever, but scientists can't be certain since they still don't know what keeps it from interacting with other galaxies. 'There must be something that prevents them from merging, but without knowing what, we cannot really predict what's going to happen in the future,' Spiniello said. It is very hard to identify fossil galaxies and confirm their nature, partly because they're relatively rare and small compared with regular galaxies such as the Milky Way, according to Sébastien Comerón, an extragalactic astronomer at the Universidad de La Laguna and the Instituto de Astrofísica de Canarias in Spain. The confirmation of a distant relic galaxy is a credit to the search strategies used to identify these objects and of modern instruments, he said. 'Relic galaxies are mysterious,' added Comerón, who was not involved with the study, in an email. 'The fact that a few galaxies are nowadays untouched relics of the first large galaxies needs an explanation.' Astronomers can't say for certain how rare relics are, but Spiniello estimates there might be 'one in millions' among all the galaxies in the universe. The INSPIRE project — which aims to find and catalogue fossil galaxies and spawned the discovery of KiDS J0842+0059 — has already identified several dozen other candidates that are in the pipeline for further scrutiny, Spiniello said. Discover your world Go beyond the headlines and explore the latest scientific achievements and fascinating discoveries. Sign up for CNN's Wonder Theory science newsletter. New instruments could make this search even more effective. Both Spiniello and Tortora are excited about Euclid, a European Space Agency telescope launched in 2023 with the goal of exploring dark matter and dark energy that will also be useful for observing fossil galaxies. 'Euclid will be transformational,' Spiniello said, 'because rather than observing one single object at a time, its wide sky survey configuration will cover a lot more. The idea is to find all the galaxies in a patch of sky, and then isolate all the ones that are ultra compact. And if you do that, then you can actually estimate how rare (fossil galaxies) are.' Confirming relic galaxy KiDS J0842+0059 at such a distance is a remarkable achievement, and the future of this field is very promising, Cappellari said in an email. 'With powerful new telescopes like James Webb and Euclid (which produced its first images just a few months ago), and on the ground with advanced adaptive optics, we can expect to find and study more of these relics at even greater distances.'
CNN
08-07-2025
- Science
- CNN
Astronomers discover ‘fossil galaxy' 3 billion light-years away
A galaxy that has remained unchanged for 7 billion years — a rarity in the universe — has been observed by astronomers, offering a glimpse into cosmic history and adding to an enigmatic collection of objects called relics or 'fossil galaxies.' These space oddities are galaxies that, after an initial phase of intense star formation, escape their expected evolutionary path. While other galaxies expand and merge with one another, the fossil galaxies remain virtually inactive. Like celestial time capsules, they provide a snapshot into the ancient universe and allow astronomers to examine the mechanism of galaxy formation. The newly discovered fossil galaxy — named KiDS J0842+0059 — is about 3 billion light-years from Earth, making it both the most distant and the first of its kind observed outside the local universe, the region of space closest to Earth that is approximately 1 billion light-years in radius. It was found by a team of astronomers led by the Italian National Institute for Astrophysics (INAF), using high-resolution imaging from the Large Binocular Telescope in Arizona. 'Relic galaxies, just by chance, did not merge with any other galaxy, remaining more or less intact through time,' said Crescenzo Tortora, a researcher at INAF and first author of a study on the finding published May 31 in the journal Monthly Notices of the Royal Astronomical Society. 'These objects are very rare because, as time goes on, the probability to merge with another galaxy naturally increases.' Astronomers believe that the most massive galaxies form in two phases, according to study coauthor Chiara Spiniello, a researcher at the University of Oxford in the UK. 'First, there's an early burst of star formation, a very quick and violent activity,' she said. 'We end up having something very compact and small, the progenitor of this relic.' The second phase, she added, is a protracted process during which galaxies that are in close proximity start interacting, merging and eating each other, causing a very dramatic change in their shapes, sizes and star populations. 'We define a relic as an object that missed almost completely this second phase, having formed at least 75% of its mass in the first phase,' Spiniello explained. The telltale feature of fossil galaxies is that they are very old, compact and dense, much more so than our own galaxy. 'They contain (billions) of stars as massive as the sun and they are not forming any new stars — they're doing essentially nothing, and they are the fossil records of the very ancient universe,' she said. 'They formed when the universe was really, really young. And then, for some reasons that we honestly don't understand yet, they did not interact. They didn't merge with other systems. They evolved undisturbed, and they remained as they were.' Fossil galaxies are crucial because they are a direct link to the massive galaxy population that existed billions of years ago, said Michele Cappellari, a professor of astrophysics at the University of Oxford who was not involved with the study. 'As 'living fossils,' they have avoided the chaotic mergers and growth that most other massive galaxies have experienced. Studying them allows us to reconstruct the conditions of the universe in its infancy and understand the initial bursts of star formation,' he said. What caused these galaxies to stop forming stars so abruptly is a major question, he added. 'Evidence from both local and (distant) observations suggests that feedback from supermassive black holes may be responsible,' Cappellari said. 'These black holes can produce powerful winds that expel or heat the gas in a galaxy, preventing further star formation. However, this remains an active area of research.' Scientists initially identified KiDS J0842+0059 in 2018 using the VLT Survey Telescope (VST) at the Paranal Observatory in Chile. That observation revealed that the galaxy was populated by very old stars but only provided an estimate of its mass and size, so a more detailed observation was required to confirm it was a relic. The Large Binocular Telescope used for this confirmation can render very sharp images due to its ability to compensate for atmospheric turbulence, which otherwise can make it difficult for Earth-based telescopes to focus on distant objects. The newly found fossil galaxy joins a group of only a handful of others that have been observed at the same level of detail, the most pristine of which — called NGC 1277 — was confirmed by the Hubble Space Telescope in 2018. NGC 1277 and KiDS J0842+0059 are very similar, but the latter is much farther away from Earth. It fits the definition of fossil galaxy almost perfectly, according to Spiniello. 'This is what we call an extreme relic,' she said, 'because almost all, or 99.5% of its stars were formed incredibly early on in cosmic time, and the galaxy did absolutely nothing thereafter.' The fossil galaxy has stars and planets, just like our own galaxy, but it is much more dense, Spiniello added. 'There will be many more stars in a tiny, tiny volume, so it'll be super crowded,' she said. 'And it will be much harder to find solar systems like ours, with many planets orbiting around it, just because of the chances of getting companion stars interfering nearby.' KiDS J0842+0059 looks to observers like it did 3 billion years ago, because that's how long it takes for the light coming from the galaxy to reach Earth. Spiniello hypothesized that the relic will likely remain as it is forever, but scientists can't be certain since they still don't know what keeps it from interacting with other galaxies. 'There must be something that prevents them from merging, but without knowing what, we cannot really predict what's going to happen in the future,' Spiniello said. It is very hard to identify fossil galaxies and confirm their nature, partly because they're relatively rare and small compared with regular galaxies such as the Milky Way, according to Sébastien Comerón, an extragalactic astronomer at the Universidad de La Laguna and the Instituto de Astrofísica de Canarias in Spain. The confirmation of a distant relic galaxy is a credit to the search strategies used to identify these objects and of modern instruments, he said. 'Relic galaxies are mysterious,' added Comerón, who was not involved with the study, in an email. 'The fact that a few galaxies are nowadays untouched relics of the first large galaxies needs an explanation.' Astronomers can't say for certain how rare relics are, but Spiniello estimates there might be 'one in millions' among all the galaxies in the universe. The INSPIRE project — which aims to find and catalogue fossil galaxies and spawned the discovery of KiDS J0842+0059 — has already identified several dozen other candidates that are in the pipeline for further scrutiny, Spiniello said. Discover your world Go beyond the headlines and explore the latest scientific achievements and fascinating discoveries. Sign up for CNN's Wonder Theory science newsletter. New instruments could make this search even more effective. Both Spiniello and Tortora are excited about Euclid, a European Space Agency telescope launched in 2023 with the goal of exploring dark matter and dark energy that will also be useful for observing fossil galaxies. 'Euclid will be transformational,' Spiniello said, 'because rather than observing one single object at a time, its wide sky survey configuration will cover a lot more. The idea is to find all the galaxies in a patch of sky, and then isolate all the ones that are ultra compact. And if you do that, then you can actually estimate how rare (fossil galaxies) are.' Confirming relic galaxy KiDS J0842+0059 at such a distance is a remarkable achievement, and the future of this field is very promising, Cappellari said in an email. 'With powerful new telescopes like James Webb and Euclid (which produced its first images just a few months ago), and on the ground with advanced adaptive optics, we can expect to find and study more of these relics at even greater distances.'
Business Mayor
22-05-2025
- Science
- Business Mayor
A dozen black holes may be 'wandering' through our galaxy — and they're the rarest type in the universe
The Milky Way has millions of small black holes and one giant supermassive black hole at its center . But does the galaxy have any medium-sized black holes? New research suggests the answer is yes: Perhaps a dozen may inhabit the Milky Way, but they are wandering freely through space and are fiendishly difficult to detect. For decades, researchers have wondered about the prevalence of intermediate-mass black holes (IMBHs). Certainly, every galaxy is capable of producing an enormous number — roughly a handful every century — of small black holes with masses of up to 100 or so times that of the sun. And it appears that when galaxies like the Milky Way first arrived on the cosmic scene, they already had companion supermassive black holes in their hearts. Our own supermassive black hole, Sagittarius A*, has a mass of 4.5 million suns. But what about the IMBHs? Theoretically, they should have masses of 10,000 to 100,000 solar masses. Finding IMBHs — or disproving their existence — has enormous implications for our understanding of black hole growth and evolution. But so far, there have been only faint, sketchy hints of IMBHs residing in dwarf galaxies, and no direct evidence that they live in a galaxy like the Milky Way. In April, a team of researchers at the University of Zurich in Switzerland explored whether our current simulations of the universe could conclusively predict if the Milky Way hosts a population of IMBHs. Their paper has been accepted for publication in the journal Monthly Notices of the Royal Astronomical Society. Related: Is our universe trapped inside a black hole? This James Webb Space Telescope discovery might blow your mind Cannibal galaxies Galaxies do not grow up alone. Instead, they develop through the cannibalization of their neighbors, by incorporating their stars — and any black holes — within their volumes. The Milky Way has consumed over a dozen dwarf galaxies , and probably many more, in its long history. Presumably, some of those dwarf galaxies held IMBHs. But the common assumption was that large black holes tend to slink down the centers of their host galaxies, where they go on to merge with the central supermassive black hole. Through their models, the researchers saw a different story unfold. They used a simulation of the evolution of a Milky Way-like galaxy and found that it can contain somewhere between five and 18 'wandering' IMBHs, which are not located near the central core but are left to roam within the disk of the galaxy. The exact number of IMBHs depends on whether they are born near the core of a soon-to-be-consumed dwarf galaxy or in its outskirts. Get the world's most fascinating discoveries delivered straight to your inbox. Although the researchers were heartened to find that the Milky Way should host a population of IMBHs, they urged caution in interpreting their results. They could not conclusively state what masses these black holes should have or where they would ultimately reside. So, while the new research strongly hints that IMBHs are out there, we do not yet know where to look.
Yahoo
26-03-2025
- Science
- Yahoo
'Very rare' black hole energy jet discovered tearing through a spiral galaxy shaped like our own
When you buy through links on our articles, Future and its syndication partners may earn a commission. Nearly a billion light-years away, a massive spiral galaxy is screaming into the void. The behemoth, nicknamed J2345-0449, is a giant radio galaxy, or "super spiral" galaxy roughly three times the size of the Milky Way. Like our own spiral galaxy, it harbors a supermassive black hole at its center. But unlike the Milky Way's center, J2345-0449's supermassive black hole emits powerful radio jets — streams of fast-moving charged particles that emit radio waves — stretching more than 5 million light-years long. Though scientists don't yet know what fuels the radio jets, a new study, published March 20 in the Monthly Notices of the Royal Astronomical Society, hints at how giant spiral galaxies could form. Such strong radio jets are "very rare for spiral galaxies," Patrick Ogle, an astronomer at the Space Telescope Science Institute in Baltimore, who was not involved in the study, told Live Science. "In general, they can have weak radio jets, but these powerful radio jets typically come from massive elliptical galaxies. The thought behind that is that to power these really big jets requires a very massive black hole, and one that's probably also spinning. So most spiral galaxies don't have massive enough black holes in the centers to create big jets like this." Related: Supermassive black hole at the heart of the Milky Way is approaching the cosmic speed limit, dragging space-time along with it Data from the Hubble Space Telescope, the Giant Metrewave Radio Telescope, and the Atacama Large Millimeter Array suggest that the radio jets currently prevent stars from forming near the galaxy's center. That's likely because the jets heat up nearby gases so much that they can't collapse into new stars — or push them out of the galaxy entirely. Though both J2345-0449 and the Milky Way are spiral galaxies, it's unlikely that we'll observe these powerful jets in our galactic hometown. "This galaxy is so different from the Milky Way," Ogle said. "It's a lot bigger, and the black hole is a lot more massive." Sagittarius A*, the supermassive black hole at the center of the Milky Way, is likely too small to produce radio jets as powerful as the ones observed in J2345-0449, Ogle told Live Science. Still, studying these rare galaxies could help scientists understand how the growth of supermassive black holes and of their host galaxies are related. Based on the shape of the group of stars at the center of the galaxy, it's possible that this black hole and its massive host galaxy have grown together in relative isolation, rather than gaining their mass from galaxy mergers. RELATED STORIES —Could the secret of supermassive black holes lie in ultralight dark matter? —Supermassive black holes in 'little red dot' galaxies are 1,000 times larger than they should be, and astronomers don't know why —Supermassive black hole spotted 12.9 billion light-years from Earth — and it's shooting a beam of energy right at us In the future, detailed studies of the galaxy's supermassive black hole could also explain what powers its massive radio jets. "The extreme rarity of such galaxies implies that whatever physical process had created such huge radio jets in J2345-0449 must be very difficult to realize and maintain for long periods of time in most other spiral/disc galaxies," the researchers wrote in the study. "Understanding these rare galaxies could provide vital clues about the unseen forces governing the universe," study co-author Shankar Ray, an astrophysicist at Christ University, Bangalore, said in a statement. "Ultimately, this study brings us one step closer to unravelling the mysteries of the cosmos, reminding us that the universe still holds surprises beyond our imagination."
