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Time of India
4 days ago
- Science
- Time of India
NASA's James Webb Space Telescope discovers earliest galaxy ever seen in the universe
Source: YouTube The James Webb Space Telescope (JWST) has once again made history by discovering the most distant and ancient galaxy ever observed, named MoM z14. Located just 280 million years after the Big Bang, this galaxy pushes the boundaries of cosmic observation. The finding highlights JWST's exceptional ability to peer into the early universe, offering unprecedented insights into the formation of the first galaxies. With its record-breaking redshift of z = 14.44, MoM z14 not only redefines our understanding of galaxy evolution but also suggests that even earlier galaxies may soon be within reach, marking a new era in astronomy. JWST discovers one of the earliest galaxies formed after the Big Bang NASA's $10 billion space telescope has spotted a galaxy that was present only 280 million years after the Big Bang, a time that astronomers refer to as "cosmic dawn." The discovery team dubbed this galaxy MoM z14—"Mother of all early galaxies" for short. "First and foremost, at the moment, this is the most distant object known to humanity," said Pieter van Dokkum, Yale University professor of Astronomy and Physics, in an interview. 'MoM z14 existed when the universe was about 280 million years old—we're getting quite close to the Big Bang. Just to put that in context, sharks have been around on Earth for a longer timespan!' Since entering service in mid-2022, the JWST has been outstanding at detecting very distant galaxies by means of an effect known as redshift. When the universe gets bigger, light from old galaxies gets stretched, moving toward the red end of the spectrum. The more distant and thus older the galaxy is, the higher the redshift. Prior to MoM z14, the then-record holder was a galaxy named JADES-GS-z14-0, seen at a redshift of z = 14.32, some 300 million years following the Big Bang. MoM z14 is all the more impressive with a redshift of z = 14.44, extending modern astronomy's observational limits. Discovery of MoM z14 reshapes the view of galaxy formation In van Dokkum's view, the discovery of MoM z14 is not merely a new record—it provokes earlier hypotheses on the early formation of galaxies. "The bigger picture here is that JWST wasn't supposed to discover any galaxies this early in the universe's history at least, or at least at this point in the mission," he states. Previous JWST models predicted significantly fewer bright galaxies in the universe's early days. Current observations indicate more than 100 such galaxies exist in the early universe—significantly more than before. What sets MoM z14 apart Aside from its record-setting age, scientists were able to glean useful insight into MoM z14's composition and structure: Size: Roughly 50 times smaller than the Milky Way. Star formation: The galaxy possesses unexplained emission lines showing that it is extremely young and quickly producing new stars. Chemical composition: Existence of carbon and nitrogen, which implies that it's not one of the absolute first generation galaxies. "These things suggest that there had to be previous galaxies made only of hydrogen and helium that existed prior to MoM z14," said van Dokkum. "MoM z14 might be the first generation of 'normal' galaxies that started making heavier elements using processes in stars." Also Read | Meteorite that hit Earth 3.26 billion years ago may have sparked good news for life, study reveals
Yahoo
06-02-2025
- Science
- Yahoo
Hubble Reveals Cosmic Bullet That Gave The Bullseye Galaxy Its Record-Breaking Rings
Just like fingerprints and snowflakes, no two galaxies in the entire Universe are exactly alike. But a new discovery 567 million light-years away really is jaw-droppingly unique. There, astronomers have found a galaxy girdled by, not one, but nine concentric rings – the aftermath of a violent encounter with a blue dwarf galaxy that shot right through its heart, sending shockwaves rippling out into space. Officially named LEDA 1313424, this galaxy has been given the appropriate title of the Bullseye Galaxy, and its serendipitous discovery is a new window into galaxy-on-galaxy crime. "We're catching the Bullseye at a very special moment in time," says astronomer Pieter van Dokkum of Yale University. "There's a very narrow window after the impact when a galaxy like this would have so many rings." So-called ring galaxies are extremely rare in the Universe, and they are thought to be the result of a very specific set of circumstances. Although space is mostly empty, galaxies are drawn together along filaments of the cosmic web, resulting in more collisions between them than you might expect. Interactions between galaxies can take many forms, and produce varied results. Ring galaxies – such as the mysterious and famous Hoag's Object – are thought to be the result of a collision in which one galaxy blasts straight through the center of another. The Bullseye Galaxy has confirmed that this process does indeed take place. Not far from the larger galaxy is a smaller one, seen in visible light images using the Hubble Space Telescope. Observations taken using the Keck Cosmic Web Imager (KCWI), which is optimized for visible blue wavelengths, revealed that this smaller galaxy is not only close to Bullseye, at a distance of just 130,000 kilometers (about 80,000 miles), but linked. "KCWI provided the critical view of this companion galaxy that we see in projection near the bullseye," says astronomer Imad Pasha of Yale University. "We found a clear signature of gas extending between the two systems, which allowed us to confirm that this galaxy is in fact the one that flew through the center and produced these rings." "The data from KCWI that identified the 'dart' or impactor is unique. There hasn't been any other case where you can so clearly see the gas streaming from one galaxy to the other, " van Dokkum adds. "That there is all this gas right between the velocity of one galaxy and the other is the key insight, showing that material is being pulled out of one galaxy, left behind by the other, or both. It physically fills up the entire space. The KCWI data enables us to see the tendril of gas that is still connecting these two galaxies." The rings are regions of higher density, where the galactic material has been pushed together by the rippling shocks. The clumping of the dust and gas triggers star formation, resulting in higher star density, which is why the rings glitter so brightly. The most distant ring is relatively faint and tenuous, and was only spotted in the KCWI images, at quite a distance from the main body of the galaxy. The entire galaxy is 250,000 light-years across. That gap between the rings is a marvel, showing that the rings propagate outwards in almost exactly the same way as predicted by theory, with the first two rings spreading quickly, with the subsequent rings forming later. It's like dropping a pebble in a pond. "If we were to look down at the galaxy directly, the rings would look circular, with rings bunched up at the center and gradually becoming more spaced out the farther out they are," Pasha says. The data provided by this marvelous galaxy will help astronomers adjust their models and theories, to better understand how such collisions play out. The researchers also hope future observations with upcoming telescopes will ferret out even more ring galaxies, lurking out there in the wide expanses of the cosmos. The research has been published in The Astrophysical Journal Letters. 10 Minutes of Violence Gave The Moon Its Very Own 'Grand Canyons' Astrophysicist Reveals The Key Facts About The Asteroid That May Hit Earth AI Can Predict Incredible Solar Storms Before They Strike
