Latest news with #JADES-GS-z13-1
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
Reuters
26-03-2025
- Science
- Reuters
Webb telescope spots galaxy at pivotal moment in the early universe
WASHINGTON, March 26 (Reuters) - Scientists using the James Webb Space Telescope have identified an ancient and faraway galaxy that provides evidence that an important transition period that brought the early universe out of its "dark ages" occurred sooner than previously thought. Webb, which by peering across vast cosmic distances is looking way back in time, observed the galaxy called JADES-GS-z13-1 as it existed about 330 million years after the Big Bang event that initiated the universe roughly 13.8 billion years ago, the researchers said. By way of comparison, Earth is about 4.5 billion years old. The universe is thought to have experienced a rapid and exponential expansion in a fraction of a second after the Big Bang. After having cooled down sufficiently, there was a period called the cosmic dark ages when the infant universe was enveloped in a dense fog of hydrogen gas in an electrically neutral state. What followed that was a time called the epoch of reionization when the universe first began to shine. Webb obtained evidence that JADES-GS-z13-1, one of the earliest-known galaxies, had made the transition into this epoch. "In JADES-GS-z13-1, Webb has confirmed one of the most distant galaxies known to date," said astrophysicist Joris Witstok of the University of Copenhagen's Cosmic Dawn Center and the Niels Bohr Institute, lead author of the study published in the journal Nature, opens new tab. "Unlike any other similarly distant galaxy, it shows a very clear, telltale signature that suggests the galaxy contains a remarkably powerful source of energetic ultraviolet radiation and has made an unexpectedly early start to reionization," Witstok said. The time when the universe's first stars, black holes and galaxies formed is called cosmic dawn. As these formed, the ultraviolet radiation they emitted chemically altered the neutral hydrogen gas in a process called reionization and allowed ultraviolet light to escape, effectively "turning on the lights" in the cosmos. "The universe, after the Big Bang, was a soup of hydrogen, helium and dark matter, slowly cooling off. Eventually, the universe was in a state where it was entirely opaque to energetic ultraviolet radiation. Hydrogen was floating around in a neutral state, meaning each little hydrogen atom had an electron bound to it," said astrophysicist and study co-author Kevin Hainline of the University of Arizona's Steward Observatory. "But as the first stars and galaxies started to form from this early universe gas, the ultraviolet radiation from young stars and from growing supermassive black holes began to knock electrons off of these neutral hydrogen atoms. And over hundreds of millions of years the universe transitioned from being opaque to ultraviolet light to transparent to ultraviolet light, which is where we are now," Hainline said. The researchers said the light that Webb detected in this galaxy may have come from vigorous star formation in the galaxy's nucleus, the presence of a growing supermassive black hole at the galactic core that is violently consuming surrounding material or some combination of those two factors. This galaxy measures about 230 light-years wide, several hundred times smaller than the Milky Way. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). Webb, which was launched by NASA in 2022 and became operational in 2023, has begun to provide a deeper understanding of the early universe. It has spotted only four galaxies dating to slightly earlier than this one, including the current record holder observed at 294 million years after the Big Bang. Those galaxies have not displayed evidence of reionization. The researchers were stunned to find that JADES-GS-z13-1 showed such evidence - in the form of a large bubble of ionized hydrogen surrounding it - because reionization was thought to have started many millions of years later. "Many independent measurements have firmly established that reionization was not fully completed until the universe was about one billion years old - 700 million years later than this galaxy - placing this galaxy at what is likely the start of the reionization era. When exactly it began is one of the big outstanding questions in cosmology," Witstok said.
