Latest news with #Lyman-alpha
Yahoo
01-05-2025
- Science
- Yahoo
Space photo of the day for April 30, 2025
When you buy through links on our articles, Future and its syndication partners may earn a commission. A new study from the NASA New Horizons mission team at the Southwest Research Institute have resulted in a first-of-its-type map from the Milky Way galaxy in an ultraviolet wavelength, revealing details in the region around our solar system. This spectrograph map, generated from data collected by NASA's New Horizons probe, depicts the relatively uniform brightness of the ultraviolet (UV) "Lyman-alpha" background surrounding the sun and its area of influence."Understanding the Lyman-alpha background helps shed light on nearby galactic structures and processes," said Dr. Randy Gladstone with the Southwest Research Institute (SwRI) in Colorado. "This research suggests that hot interstellar gas bubbles like the one our solar system is embedded within may actually be regions of enhanced hydrogen gas emissions at a wavelength called Lyman alpha." Lyman-alpha is a specific wavelength of UV light emitted and scattered by hydrogen atoms. It is useful when studying distant stars, galaxies and the interstellar medium, as it can help detect the composition, temperature and movement of these distant this spectrograph map, the black dots represent approximately 90,000 known UV-bright stars in our galaxy. New Horizons, which began as the first mission to flyby Pluto, collected baseline data about Lyman-alpha emissions during its initial journey to the small, icy world. After the spacecraft's primary objectives at Pluto were completed, New Horizons' ultraviolet spectrograph (named "Alice") was used to make more frequent surveys of Lyman-alpha emissions as New Horizons traveled farther from the sun. These observations included an extensive set of scans in 2023 that mapped roughly 83% of the sky. Before this map was released, scientists theorized that a wall of interstellar hydrogen atoms would accumulate as they reached the edge of our heliosphere — the region of our galaxy where the solar wind from our sun reaches and interacts with the interstellar medium. New Horizons data saw nothing to indicate that this "wall" was an important source of Lyman-alpha emissions."These are really landmark observations, in giving the first clear view of the sky surrounding the solar system at these wavelengths, both revealing new characteristics of that sky and refuting older ideas that the Alice New Horizons data just doesn't support," said Dr. Alan Stern. the mission's principal investigator at SwRI. "This Lyman-alpha map also provides a solid foundation for future investigations to learn even more." Read more about New Horizons' mission after leaving Pluto and other recent research based on Lyman-alpha emissions. You can also find the scientific paper describing the SwRI map and its findings in The Astronomical Journal.
Yahoo
02-04-2025
- Science
- Yahoo
Scientists Spotted Evidence of an Unseen Universe
The James Webb Space Telescope's JADES survey recently observed a galaxy that shouldn't be visible, because it existed only 300 million years after the Big Bang. At that point in cosmic history, the universe was shrouded by neutral hydrogen, and most objects and phenomena would not be visible until nearly a billion years later. For now, researchers think the light might be coming from the first stars to exist, or outflows from a supermassive black hole at the galactic core. But the source remains unknown. Deep in the universe are stars and galaxies and objects so distant that the light we're watching them produce is billions of years old. But there is one ancient light we can see that we shouldn't be seeing at all. As part of the James Webb Space Telescope Advanced Deep Extragalactic Survey (JADES), NASA's James Webb Space Telescope (JWST) spotted something that should not be visible to us—the galaxy JADES-GS-z13-1. This galaxy existed only 330 million years after the Big Bang, which was very much still the universe's baby phase. Webb was able to spot GS-z13-1 in the first place by picking up on clear Lyman-alpha emissions from the galaxy. These emissions are released when an electron in a neutral hydrogen atom is excited by a photon that is energetic enough, and are very commonly detected throughout the cosmos. But here's the thing—they're very commonly detected now. Technically speaking, we should not be able to detect Lyman-alpha emissions from just 330 million years after the Big Bang. Shrouded in neutral hydrogen, which absorbs light, the universe was mostly opaque during its earliest days, and remained so until about a billion years after its birth. It was only during the epoch of reionization that light from stars became powerful enough to tear apart these atoms, rip off their electrons, and escape through the cloud. With all that neutral hydrogen now ionized—meaning that it was positively charged, as a result of losing its negatively charged electrons—the universe became transparent. That's the first moment at which we should be able to detect Lyman-alpha emissions. But if this didn't happen until about a billion years after the Big Bang, how is it possible that scientists can see GS-z13-1, which existed when its light should have been obscured? 'The unexpected Lyman-alpha emission indicates the galaxy is a prolific producer and leaker of ionizing photons,' NASA and ESA researchers said in a study recently published in the journal Nature. 'This suggests massive, hot stars or an active galactic nucleus (AGN) have created an early reionized region to prevent complete [suppression] of Lyman-alpha.' It is possible that the first stars to exist—known as Population III or Pop III stars—are the source of the light coming from GS-z13-1. These stars are thought to have been much more massive and luminous than stars that exist now, and it would be an incredible discovery if it was confirmed that the Lyman-alpha emissions are coming from Pop III stars. But there are some issues with this theory—the stellar mass predicted from the galaxy is not high enough to allow for these stars, for example. There are also some other emissions expected from Pop III stars that are missing from GS-z13-1. The researchers think another possibility is the supermassive black hole in the galaxy's active galactic nucleus, or AGN. Supermassive black holes accrete and devour so much matter that they belch out enormous and extremely bright outflows of gas, which scientists think could have been enough to reionize just one section of the universe a little bit early. For now, we're all still in the dark. But scientists are grateful for—if confused by the existence of—this ancient flashlight. You Might Also Like Can Apple Cider Vinegar Lead to Weight Loss? Bobbi Brown Shares Her Top Face-Transforming Makeup Tips for Women Over 50
Yahoo
01-04-2025
- Science
- Yahoo
Scientists Spotted Evidence of an Unseen Universe—Even Though That Should Be Impossible
The James Webb Space Telescope's JADES survey recently observed a galaxy that shouldn't be visible, because it existed only 300 million years after the Big Bang. At that point in cosmic history, the universe was shrouded by neutral hydrogen, and most objects and phenomena would not be visible until nearly a billion years later. For now, researchers think the light might be coming from the first stars to exist, or outflows from a supermassive black hole at the galactic core. But the source remains unknown. Deep in the universe are stars and galaxies and objects so distant that the light we're watching them produce is billions of years old. But there is one ancient light we can see that we shouldn't be seeing at all. As part of the James Webb Space Telescope Advanced Deep Extragalactic Survey (JADES), NASA's James Webb Space Telescope (JWST) spotted something that should not be visible to us—the galaxy JADES-GS-z13-1. This galaxy existed only 330 million years after the Big Bang, which was very much still the universe's baby phase. Webb was able to spot GS-z13-1 in the first place by picking up on clear Lyman-alpha emissions from the galaxy. These emissions are released when an electron in a neutral hydrogen atom is excited by a photon that is energetic enough, and are very commonly detected throughout the cosmos. But here's the thing—they're very commonly detected now. Technically speaking, we should not be able to detect Lyman-alpha emissions from just 330 million years after the Big Bang. Shrouded in neutral hydrogen, which absorbs light, the universe was mostly opaque during its earliest days, and remained so until about a billion years after its birth. It was only during the epoch of reionization that light from stars became powerful enough to tear apart these atoms, rip off their electrons, and escape through the cloud. With all that neutral hydrogen now ionized—meaning that it was positively charged, as a result of losing its negatively charged electrons—the universe became transparent. That's the first moment at which we should be able to detect Lyman-alpha emissions. But if this didn't happen until about a billion years after the Big Bang, how is it possible that scientists can see GS-z13-1, which existed when its light should have been obscured? 'The unexpected Lyman-alpha emission indicates the galaxy is a prolific producer and leaker of ionizing photons,' NASA and ESA researchers said in a study recently published in the journal Nature. 'This suggests massive, hot stars or an active galactic nucleus (AGN) have created an early reionized region to prevent complete [suppression] of Lyman-alpha.' It is possible that the first stars to exist—known as Population III or Pop III stars—are the source of the light coming from GS-z13-1. These stars are thought to have been much more massive and luminous than stars that exist now, and it would be an incredible discovery if it was confirmed that the Lyman-alpha emissions are coming from Pop III stars. But there are some issues with this theory—the stellar mass predicted from the galaxy is not high enough to allow for these stars, for example. There are also some other emissions expected from Pop III stars that are missing from GS-z13-1. The researchers think another possibility is the supermassive black hole in the galaxy's active galactic nucleus, or AGN. Supermassive black holes accrete and devour so much matter that they belch out enormous and extremely bright outflows of gas, which scientists think could have been enough to reionize just one section of the universe a little bit early. For now, we're all still in the dark. But scientists are grateful for—if confused by the existence of—this ancient flashlight. 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
29-03-2025
- Science
- Yahoo
James Webb telescope finds 'totally unexpected' ancient galaxy that defies theory
When you buy through links on our articles, Future and its syndication partners may earn a commission. An ancient galactic lighthouse is shining through the fog of the early universe, new James Webb Space Telescope (JWST) observations reveal. Researchers discovered bright ultraviolet (UV) light coming from an ancient, distant galaxy. The findings, published March 26 in the journal Nature, suggest that the universe's first stars modified their surroundings even earlier than expected. Shortly after the Big Bang, the universe was a soup of protons, neutrons and electrons. As the universe cooled, the protons and neutrons combined to form positively charged hydrogen ions, which then attracted negatively charged electrons to create a fog of neutral hydrogen atoms. This fog absorbed light with short wavelengths, such as UV light, blocking it from reaching farther into the universe. But as the first stars and galaxies formed, they emitted enough UV light to knock the electrons back off the hydrogen atoms, allowing UV light out once again. Though this "Era of Reionization" is thought to have ended about a billion years after the Big Bang, scientists still aren't sure exactly when the first stars formed — or when the Era of Reionization began. Related: James Webb telescope reveals 'cosmic tornado' in best detail ever — and finds part of it is not what it seems The new findings could help narrow down that starting point. Using JWST, researchers observed an ancient galaxy known as JADES-GS-z13-1. The galaxy is so far from Earth that we're observing it as it appeared just 330 million years after the Big Bang. In the JWST data, the scientists spotted bright light at a specific wavelength known as the Lyman-alpha emission, which is produced by hydrogen. Though the light started out as ultraviolet, the universe's expansion over more than 13 billion years has stretched it out into the infrared region, making it visible to JWST's sensors. For the Lyman-alpha emission to reach Earth today, JADES-GS-z13-1 must have ionized enough of the hydrogen gas around it to allow the UV light to escape — something scientists hadn't expected so early in the universe's development. "GS-z13-1 is seen when the universe was only 330 million years old, yet it shows a surprisingly clear, telltale signature of Lyman-alpha emission that can only be seen once the surrounding fog has fully lifted," study co-author Roberto Maiolino, an astrophysicist at the University of Cambridge, said in a statement. "This result was totally unexpected by theories of early galaxy formation and has caught astronomers by surprise." RELATED STORIES —James Webb telescope discovers 2 of the oldest galaxies in the universe —James Webb telescope reveals 3 possible 'dark stars' — galaxy-sized objects powered by invisible dark matter —'I was astonished': Ancient galaxy discovered by James Webb telescope contains the oldest oxygen scientists have ever seen Researchers still don't know what produced the Lyman-alpha radiation in JADES-GS-z13-1. The light might come from extremely hot and massive early stars, or it might be produced by an early supermassive black hole. "We really shouldn't have found a galaxy like this, given our understanding of the way the universe has evolved," study co-author Kevin Hainline, an astronomer at the University of Arizona, said in the statement. "We could think of the early universe as shrouded with a thick fog that would make it exceedingly difficult to find even powerful lighthouses peeking through, yet here we see the beam of light from this galaxy piercing the veil." "This fascinating emission line has huge ramifications for how and when the universe reionized," Hainline concluded.
Yahoo
28-03-2025
- Science
- Yahoo
Galaxy Caught Turning on Lights at Cosmic Dawn, Stunning Astronomers
A galaxy spotted just 330 million years after the Big Bang has been implicated in bringing light to the choking dark of the early Universe. It's called JADES-GS-z13-1, and an analysis of the very faint light it has sent from more than 13.4 billion years ago reveals that it played a role in the Epoch of Reionization – the billion-year process that cleared the opaque fog that filled the early Universe, allowing light to stream freely. This epoch of the Universe's history is really hard to see, making the mechanisms behind it something of a mystery. JADES-GS-z13-1 literally sheds light into an age of cosmic darkness. The result is a signature emission called Lyman-alpha which is emitted by hydrogen as it changes energy states and can only be seen once reionization has taken place. "The early Universe was bathed in a thick fog of neutral hydrogen," says astrophysicist Roberto Maiolino of the University of Cambridge and University College London in the UK. "Most of this haze was lifted in a process called reionization, which was completed about one billion years after the Big Bang. GS-z13-1 is seen when the Universe was only 330 million years old, yet it shows a surprisingly clear, telltale signature of Lyman-alpha emission that can only be seen once the surrounding fog has fully lifted. This result was totally unexpected by theories of early galaxy formation and has caught astronomers by surprise." Here's how the story goes. At the beginning of the Universe as we know it, within minutes of the Big Bang, space was filled with a hot, dense fog of plasma consisting of small atomic nuclei and free electrons. What little light there was wouldn't have penetrated this fog; photons would simply have scattered off the electrons floating around, effectively making the Universe dark. After about 300,000 years, as the Universe cooled, protons and electrons began to come together to form neutral hydrogen (and a little bit of helium) gas. Most wavelengths of light could penetrate this neutral medium, but there was little in the way of light to produce it. But from this hydrogen and helium, the first stars and galaxies were born. Those first light sources delivered powerful radiation that knocked electrons off the neutral hydrogen, returning it to an ionized state once more. By this point, however, the Universe had expanded so much that the gas was exponentially more diffuse, allowing light to pass through more easily and begin its long journey across the stretches of time and space. By about 1 billion years after the Big Bang, following the period known as the Cosmic Dawn, the Universe was transparent, the way we see it today. Et voilà! The lights were on. The problem with JADES-GS-z13-1 is that, even if it's participating in reionization, we still shouldn't be able to see it. The space immediately around the galaxy would be ionized, creating a bubble of clarity about 650,000 light-years across at the time we see it; but fog should still be wrapped around this little cavity of brilliance the galaxy has carved in space-time. "We really shouldn't have found a galaxy like this, given our understanding of the way the Universe has evolved," says astronomer Kevin Hainline of the University of Arizona in the US. "We could think of the early Universe as shrouded with a thick fog that would make it exceedingly difficult to find even powerful lighthouses peeking through, yet here we see the beam of light from this galaxy piercing the veil. This fascinating emission line has huge ramifications for how and when the Universe reionized." We thought we had a pretty good handle on the timeline and process of reionization. JADES-GS-z13-1 throws that for a loop. One possible explanation is that a rapidly feeding black hole is responsible, causing material around it to heat up and blaze with light. Another explanation for the Lyman-alpha brightness could be a large number of really massive, hot stars, between 100 and 300 times the mass of the Sun. Both prospects are intriguing, since each offers a different window into the infancy of the Universe; but, at this point, neither can be confirmed. Future observations of the strange galaxy are planned to help astronomers learn more. One thing that is becoming clear, like the space around JADES-GS-z13-1: the more we learn about the early Universe, the more confusing it gets. "Following in the footsteps of the Hubble Space Telescope, it was clear Webb would be capable of finding ever more distant galaxies," explains astronomer Peter Jakobsen of the University of Copenhagen in Denmark. "As demonstrated by the case of GS-z13-1, however, it was always going to be a surprise what it might reveal about the nature of the nascent stars and black holes that are formed at the brink of cosmic time." The research has been published in Nature. Did Life Ever Exist on Venus? Scientists Develop New Equation to Find Out. Giant 'Space Tornadoes' Discovered Raging in Milky Way's Turbulent Heart First-Ever Images of Neptune's Eerie Glow Finally Reveal Missing Aurora
