Latest news with #JWST
Hans India
a day ago
- Science
- Hans India
JWST uncovers new kind of black holes linking classical quasars and 'Little Red Dots'
Astronomers have identified a previously unseen class of supermassive black holes in the early universe by combining Subaru Telescope data with follow-up observations from the James Webb Space Telescope (JWST). These dust-enshrouded quasars, dating to within the first billion years after the Big Bang, bridge the gap between well-known, brightly shining quasars and the faint 'Little Red Dots' JWST first spotted in late 2022. For over a decade, ground-based surveys with Subaru flagged galaxies whose light signatures hinted at more than just star formation, but technical limits prevented a definitive identification. By re-examining 13 of these candidates using JWST's sensitive infrared spectrograph, an international team detected the telltale broad emission lines and high-velocity gas flows that confirm active galactic nuclei powered by supermassive black holes cloaked in heavy dust. Of those 13 galaxies, nine revealed these hidden quasars, whose intrinsic brightness rivals that of classical quasars but whose optical light is heavily reddened by surrounding dust—mirroring the characteristics of the 'Little Red Dots.' Lead author Yoshiki Matsuoka of Ehime University remarked, 'We were surprised to find that obscured quasars are so abundant in the early universe,' suggesting that many young black holes have eluded detection in previous surveys. Independent expert Jorryt Matthee of IST Austria, who was not involved in the study, praised the robustness of the spectral data and noted that this new population likely represents the 'missing link' between the rare, brilliant quasars and the smaller, dimmer red dots. As more of these objects are confirmed, astronomers will be able to estimate the masses of their black holes and host galaxies, offering fresh insights into how the earliest galactic giants grew. Building on these promising results, Matsuoka's team plans to use JWST to study roughly 30 more Subaru-selected targets. By mapping the environments and gas dynamics around these hidden quasars, researchers hope to unravel the origins of the Little Red Dots and refine our understanding of black-hole evolution at cosmic dawn.
Scientific American
a day ago
- Science
- Scientific American
Why Do We Launch Space Telescopes?
On April 24, 1990, NASA and the European Space Agency launched an astronomical revolution. When the Space Shuttle Discovery roared into the sky on that day, it carried the Hubble Space Telescope in its payload bay, and the astronauts aboard deployed it into low-Earth orbit soon thereafter. Hubble is not the largest telescope ever built—in fact, with a 2.4-meter mirror, it's actually considered by astronomers to be small—but it has a huge advantage over its earthbound siblings: it's above essentially all of our planet's atmosphere. That lofty perch makes Hubble's views sharper and deeper—and even broader, by allowing the telescope to gather types of light invisible to human eyes and otherwise blocked by Earth's air. And, after 35 years in orbit, Hubble is still delivering incredible science and cosmic vistas of breathtaking beauty. Launching telescopes into space takes much more effort and money than building them on the ground, though. Space telescopes also tend to be smaller than ground-based ones; they have to fit into the payload housing of a rocket, limiting their size. That restriction can be minimized by designing an observatory to launch in a folded-up form that then unfurls in space, as with the James Webb Space Telescope (JWST) —but this approach almost inevitably piles on more risk, complexity and cost. Given those considerable obstacles, one might ask whether space telescopes are ever really worth the hassle. 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. The short answer is: Yes, of course! For astronomical observations, getting above Earth's atmosphere brings three very basic but extremely powerful advantages. The first is that the sky is much darker in space. We tend to think of our atmosphere as being transparent, at least when it's cloudless. But unwanted light still suffuses Earth's air, even on the clearest night at the planet's darkest spot. Light pollution—unneeded illumination cast up into the sky instead of down to the ground—accounts for some of this, but the air also contains sunlight-energized molecules that slowly release this energy as a feeble trickle of visible light. This 'airglow' is dim but, even at night, outshines very faint celestial objects, limiting what ground-based telescopes can see. It's a problem of contrast, like trying to hear a whisper in a crowded restaurant. The quieter the background noise level, the better you can hear faint sounds. It's the same with the sky: a darker sky allows fainter objects to be seen. The second advantage to observing from space is that this escapes the inherent unsteadiness of our air. Turbulence in the atmosphere is the reason stars twinkle. That's anathema to astronomers; the twinkling of a star smears out its light during an observation, blurring small structures together and limiting a ground-based telescope's effective resolution (that is, how well it can distinguish between two closely spaced objects). This also makes faint objects even dimmer and harder to detect because their light isn't concentrated into a single spot and is instead diffused. Above the atmosphere, the stars and nebulas and galaxies appear crisp and unwavering, allowing us to capture far greater detail. The third reason to slip the surly bonds of Earth is that our air is extremely good at shielding us from many wavelengths of light our eyes cannot see. Ultraviolet light has wavelengths shorter than visible light (the kind our eyes detect), and while some of it reaches Earth's surface from space—enough from the sun, at least, to cause sunburns—a lot of it is instead absorbed by the air. In fact, light with a wavelength shorter than about 0.3 micron is absorbed completely. (That's a bit shorter than that of violet light, the shortest we can see, at about 0.38 micron.) So any sufficiently shortwave light—not just ultraviolet, but also even more cell-damaging x-rays and gamma rays—is sopped up by molecules in the air. That's good for human health but not great for observations of astronomical phenomena that emit light in these regimes. This happens with longer wavelengths, too. Carbon dioxide and water are excellent absorbers of infrared light, preventing astronomers on the ground from seeing most of those emissions from cosmic objects, too. As we've learned with JWST, observations in infrared can show us much about the universe that would otherwise lie beyond our own limited visual range. As just one example, the light from extremely distant galaxies is redshifted by the cosmic expansion into infrared wavelengths, where JWST excels. In fact, space telescopes that can see in different wavelengths have been crucial for discovering all sorts of surprising celestial objects and events. X-rays were critical in finding the first black holes, whose accretion disks generate high-energy light as the matter within them falls inward. Gamma-ray bursts, immensely powerful explosions, were initially detected via space-based observations. Brown dwarfs (which are essentially failed stars) emit very little visible light but are bright enough in the infrared that we now count them by the thousands in our catalogs. Observing in these other kinds of light is critical for unveiling important details about the underlying astrophysics of these and other phenomena. It's only by combining observations across the electromagnetic spectrum that we can truly understand how the universe works. Still, launching telescopes into space is a lot of trouble and expense. Official work on Hubble started in the 1970s, but delays kept it on the ground for decades. It also cost a lot of money: roughly $19.5 billion total between 1977 and 2021, in today's dollars. (Operational costs have been about $100 million per year in recent years, but Hubble is facing budget cuts.) JWST was $10 billion before it even launched, and running it adds about $170 million annually to the project's total price tag. Compare that with the European Southern Observatory's Extremely Large Telescope, or ELT, a 39-meter behemoth currently under construction that has an estimated budget of under $2 billion. Building on the ground is simpler, requires less testing and is more fault-tolerant, allowing much more bang for the buck. The capabilities of ground-based versus space-based telescopes are different, however. In general, big earthbound telescopes can collect a lot of light and see faint structures, but except for the ELT, they don't have the resolution of their space-based counterparts and can't see light outside the transparency window of our planet's air. Also, not every observation needs to be done from space; many can be done just fine from the ground, freeing up time on the more expensive and tightly scheduled space telescopes. Pitting these two kinds of facilities against each other—why have one when we can have the other?—is the wrong way to think about this. They don't compete; they complement. Together they provide a much clearer view of the cosmos than either can give by itself. Astronomy needs both.
Yahoo
2 days ago
- General
- Yahoo
James Webb telescope uncovers new, 'hidden' type of black hole never seen before
When you buy through links on our articles, Future and its syndication partners may earn a commission. Astronomers using the James Webb Space Telescope (JWST) have unveiled a hidden population of supermassive black holes in the early universe that have never been seen before. This fascinating discovery could bridge the gap between classical quasars and the lesser-known "Little Red Dots" recently detected near the dawn of time, which may represent baby quasars. Classical quasars are active galactic nuclei (AGNs), galaxies dominated by actively-feeding black holes that are surrounded by complex dust environments. These AGNs are powered by large supermassive black holes and are extremely bright, which makes them easily detectable despite the surrounding dust. But in December 2022, scientists using JWST discovered a strange new type of AGN that they dubbed Little Red Dots — so named because they look like tiny, faint red spots in images. In contrast to classical quasars, these dots are smaller and dimmer, and they tend to be hidden by a lot of dust. The connection between the two AGN types remains a mystery, prompting astronomers to search for objects with intermediate properties. For more than a decade, astronomers have been looking out for distant quasars with the Subaru Telescope in Hawaii, and have identified several galaxies within the first billion years after the Big Bang. While the light from these galaxies was not typical of a classical quasar, the intensity of light was too high to be due to star formation alone. They suspected that these galaxies harbored AGNs, which were somehow hidden in dust. But astronomers could not prove that they were indeed a different type of AGN due to technical limitations in telescopes at the time. Related: James Webb telescope discovers frozen water around a distant, sunlike star Now, using the more sensitive JWST to reanalyze those puzzling objects spotted by Subaru, an international team of astronomers has confirmed the presence of fast-moving gas under the influence of the strong gravity of supermassive black holes. This proved that the objects were AGNs after all — but a type never seen before. The findings were reported on May 7 in a study uploaded to the preprint database arXiv. Out of 13 distant galaxies examined in the new study, astronomers found that 9 displayed clear signs of a new population of active, supermassive black holes — and their patterns of light carry the unmistakable fingerprint of quasars hidden behind heavy dust. "We were surprised to find that obscured quasars are so abundant in the early universe," Yoshiki Matsuoka, associate professor at the Research Center for Space and Cosmic Evolution at Ehime University, and lead author of the study, told Live Science in an email. "This means that a significant fraction of active [supermassive black holes] have been overlooked in the past ground-based surveys." These newly discovered "hidden" quasars are as bright as classical quasars, but the level of dust obscuring their light resembles what astronomers have found in the case of Little Red Dots. Combining the ground-based data with JWST's detailed follow-up observations, researchers may have found the missing link between rare, bright quasars and the more common Little Red Dots seen by JWST. "These results are robust due to the high-quality of the light spectra of these objects, with clear signatures of gas powered by supermassive black holes," Jorryt Matthee, assistant professor and head of the research group Astrophysics of Galaxies at the Institute of Science and Technology Austria, who was not involved in the new study, told Live Science. "While the number of new objects is high, it is not so unexpected," Matthee said. "The gap between the two known populations is very vast, and indeed, these new objects may belong to that missing population, but there's probably more." He adds that as astronomers find more of these hidden quasars and gather additional observations, the light they emit can be used to estimate the masses of stars and supermassive black holes in their host galaxies. This information will offer fresh insights into how these giants evolved in the early universe. Additionally, by comparing the number of hidden quasars discovered with what theoretical models predict, scientists can test whether these findings challenge the standard model of the universe. RELATED STORIES —'Baby quasars' spotted by James Webb telescope could transform our understanding of monster black holes —Astronomers find hundreds of 'hidden' black holes — and there may be billions or even trillions more —James Webb telescope spots rare 'missing link' galaxy at the dawn of time Meanwhile, the team led by Matsuoka plans to use JWST to observe 30 more objects from the same Subaru Telescope sample. They are hoping to uncover more hidden quasars, including Little Red Dots. First reported just a few years ago, Little Red Dots are still shrouded in mystery. They're poorly understood because they appear so faint and tiny in the sky. Matsuoka explained that by combining their results with other follow-up observations to study the surrounding gas and environments, the hidden quasars will provide a vital clue to unveiling the mysterious nature of Little Red Dots.
News18
2 days ago
- Science
- News18
Universe's Earliest Light Revealed: James Webb Telescope Captures Stunning Image Of Cosmic Dawn
Last Updated: James Webb Space Telescope has captured the deepest and clearest image to date, offering us a glimpse of the universe's beginning, known as the 'Cosmic Dawn' The James Webb Space Telescope (JWST), the most powerful space observatory ever built, has achieved a remarkable feat that will excite everyone interested in space science. This telescope has captured the deepest and clearest image to date, offering us a glimpse of the universe's beginning, known as the 'Cosmic Dawn.' 'Cosmic Dawn' refers to the period when the universe was very young, just a few hundred million years old. Scientists believe that during this time, stars and galaxies began forming for the first time, roughly 13 billion years ago. Until now, it has been very difficult to observe such ancient objects directly. advetisement How Was This Picture Taken? In this historic image, the James Webb Telescope focused on a massive galaxy cluster called 'Abell S1063,' located about 4.5 billion light years away from Earth. This cluster was previously observed by the Hubble Telescope, but James Webb's more powerful infrared camera, NIRCam, allowed it to see deeper into space. The telescope observed this region continuously for 120 hours, capturing nine different images that were combined into a single, stunning picture. This is being called James Webb's deepest view yet. What Was Seen In The Picture? Behind the large galaxies in the image, faint, curved lines of light are visible. These lines are actually light from extremely distant galaxies that cannot be seen directly. The gravitational lensing effect caused by the massive galaxy cluster bends their light towards us, making them visible. Why Is This Discovery Special? Scientists say this image provides evidence that some galaxies formed just 200 million years after the universe came into existence. In other words, we can now witness the moments when the universe first began to 'shine.' The data also hints at glimpses of the very first stars, which is a major breakthrough. How close are we to understanding the universe's mysteries? This image is not just a scientific achievement; it is like a window into time. It proves that we have taken the first step towards uncovering the true story of the universe's birth. The success of the James Webb Telescope shows that humanity is now closer than ever to solving some of the oldest mysteries of time and space. Watch India Pakistan Breaking News on CNN-News18. Get breaking news, in-depth analysis, and expert perspectives on everything from geopolitics to diplomacy and global trends. Stay informed with the latest world news only on News18. Download the News18 App to stay updated! tags : galaxies James Webb Space Telescope space telescope First Published:
Ammon
3 days ago
- Science
- Ammon
James Webb telescope discovers farthest known galaxy in the universe
Ammon News - The James Webb Space Telescope (JWST) has spotted the most distant galaxy observed to date — breaking its own record yet again. The galaxy, dubbed MoM-z14, is "the most distant spectroscopically confirmed source to date, extending the observational frontier to a mere 280 million years after the Big Bang," researchers wrote in a new study that appeared May 23 on the preprint server arXiv. In other words, the galaxy emitted light just 280 million years after the birth of the universe; after its long journey across the cosmos, that light is only now reaching Earth and JWST's infrared sensors. "It's pretty exciting," Charlotte Mason, an astrophysicist at the University of Copenhagen who wasn't involved in the study, told New Scientist. "It confirms that there really are these very bright galaxies in the universe." Since beginning operation in 2022, JWST has spotted more bright, ancient galaxies than scientists expected, challenging previous theories about the universe's infancy. "This unexpected population has electrified the community and raised fundamental questions about galaxy formation in the first 500 [million years after the Big Bang]," the authors wrote. Live Science
