Webb Telescope sees galaxy in mysteriously clearing fog of early Universe
A key goal of the NASA/ESA/CSA James Webb Space Telescope has been to see further than ever before into the distant past of our Universe, when the first galaxies were forming after the Big Bang, a period know as cosmic dawn.
Researchers studying one of those very early galaxies have now made a discovery in the spectrum of its light, that challenges our established understanding of the Universe’s early history. Their results are reported in the journal Nature.
Webb discovered the incredibly distant galaxy JADES-GS-z13-1, observed at just 330 million years after the Big Bang. Researchers used the galaxy’s brightness in different infrared filters to estimate its redshift, which measures a galaxy’s distance from Earth based on how its light has been stretched out during its journey through expanding space.
The NIRCam imaging yielded an initial redshift estimate of 12.9. To confirm its extreme redshift, an international team led by Dr Joris Witstok, previously of the University of Cambridge’s Kavli Institute for Cosmology, observed the galaxy using Webb’s Near-Infrared Spectrograph (NIRSpec) instrument.
The resulting spectrum confirmed the redshift to be 13.0. This equates to a galaxy seen just 330 million years after the Big Bang, a small fraction of the Universe’s present age of 13.8 billion years.
But an unexpected feature also stood out: one specific, distinctly bright wavelength of light, identified as the Lyman-α emission radiated by hydrogen atoms. This emission was far stronger than astronomers thought possible at this early stage in the Universe’s development.
“The early Universe was bathed in a thick fog of neutral hydrogen,” said co-author Professor Roberto Maiolino from Cambridge’s Kavli Institute for Cosmology. “Most of this haze was lifted in a process called reionisation, 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-α 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.”
Before and during the epoch of reionisation, neutral hydrogen fog surrounding galaxies blocked any energetic ultraviolet light they emitted, much like the filtering effect of coloured glass. Until enough stars had formed and were able to ionise the hydrogen gas, no such light — including Lyman-α emission — could escape from these fledgling galaxies to reach Earth.
The confirmation of Lyman-α radiation from this galaxy has great implications for our understanding of the early Universe. “We really shouldn’t have found a galaxy like this, given our understanding of the way the Universe has evolved,” said co-author Kevin Hainline from the University of Arizona. “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.”
The source of the Lyman-α radiation from this galaxy is not yet known, but it may include the first light from the earliest generation of stars to form in the Universe. “The large bubble of ionised hydrogen surrounding this galaxy might have been created by a peculiar population of stars — much more massive, hotter and more luminous than stars formed at later epochs, and possibly representative of the first generation of stars,” said Witstok, who is now based at the Cosmic Dawn Center at the University of Copenhagen. A powerful active galactic nucleus, driven by one of the first supermassive black holes, is another possibility identified by the team.
The team plans further follow-up observations of GS-z13-1, aiming to obtain more information about the nature of this galaxy and origin of its strong Lyman-α radiation. Whatever the galaxy is concealing, it is certain to illuminate a new frontier in cosmology.
JWST is an international partnership between NASA, ESA and the Canadian Space Agency (CSA). The data for this result were captured as part of the JWST Advanced Deep Extragalactic Survey (JADES).
Reference:
Joris Witstok et al. ‘Witnessing the onset of reionization through Lyman-α emission at redshift 13.’ Nature (2025). DOI: 10.1038/s41586-025-08779-5
Adapted from an ESA media release.
Astronomers have identified a bright hydrogen emission from a galaxy in the very early Universe. The surprise finding is challenging researchers to explain how this light could have pierced the thick fog of neutral hydrogen that filled space at that time.
This result was totally unexpected by theories of early galaxy formation and has caught astronomers by surpriseRoberto MaiolinoESA/Webb, NASA, STScI, CSA, JADES CollaborationJADES-GS-z13-1 in the GOODS-S field
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NASA’s Webb Captures Neptune’s Auroras For First Time
NASA, ESA, CSA, STScI, Heidi Hammel (AURA), Henrik Melin (Northumbria University), Leigh Fletcher (University of Leicester), Stefanie Milam (NASA-GSFC)
Long-sought auroral glow finally emerges under Webb’s powerful gaze
For the first time, NASA’s James Webb Space Telescope has captured bright auroral activity on Neptune. Auroras occur when energetic particles, often originating from the Sun, become trapped in a planet’s magnetic field and eventually strike the upper atmosphere. The energy released during these collisions creates the signature glow.
In the past, astronomers have seen tantalizing hints of auroral activity on Neptune, for example, in the flyby of NASA’s Voyager 2 in 1989. However, imaging and confirming the auroras on Neptune has long evaded astronomers despite successful detections on Jupiter, Saturn, and Uranus. Neptune was the missing piece of the puzzle when it came to detecting auroras on the giant planets of our solar system.
“Turns out, actually imaging the auroral activity on Neptune was only possible with Webb’s near-infrared sensitivity,” said lead author Henrik Melin of Northumbria University, who conducted the research while at the University of Leicester. “It was so stunning to not just see the auroras, but the detail and clarity of the signature really shocked me.”
The data was obtained in June 2023 using Webb’s Near-Infrared Spectrograph. In addition to the image of the planet, astronomers obtained a spectrum to characterize the composition and measure the temperature of the planet’s upper atmosphere (the ionosphere). For the first time, they found an extremely prominent emission line signifying the presence of the trihydrogen cation (H3+), which can be created in auroras. In the Webb images of Neptune, the glowing aurora appears as splotches represented in cyan.
Image A:Neptune’s Auroras – Hubble and Webb At the left, an enhanced-color image of Neptune from NASA’s Hubble Space Telescope. At the right, that image is combined with data from NASA’s James Webb Space Telescope. The cyan splotches, which represent auroral activity, and white clouds, are data from Webb’s Near-Infrared Spectrograph (NIRSpec), overlayed on top of the full image of the planet from Hubble’s Wide Field Camera 3. NASA, ESA, CSA, STScI, Heidi Hammel (AURA), Henrik Melin (Northumbria University), Leigh Fletcher (University of Leicester), Stefanie Milam (NASA-GSFC)
“H3+ has a been a clear signifier on all the gas giants — Jupiter, Saturn, and Uranus — of auroral activity, and we expected to see the same on Neptune as we investigated the planet over the years with the best ground-based facilities available,” explained Heidi Hammel of the Association of Universities for Research in Astronomy, Webb interdisciplinary scientist and leader of the Guaranteed Time Observation program for the Solar System in which the data were obtained. “Only with a machine like Webb have we finally gotten that confirmation.”
The auroral activity seen on Neptune is also noticeably different from what we are accustomed to seeing here on Earth, or even Jupiter or Saturn. Instead of being confined to the planet’s northern and southern poles, Neptune’s auroras are located at the planet’s geographic mid-latitudes — think where South America is located on Earth.
This is due to the strange nature of Neptune’s magnetic field, originally discovered by Voyager 2 in 1989 which is tilted by 47 degrees from the planet’s rotation axis. Since auroral activity is based where the magnetic fields converge into the planet’s atmosphere, Neptune’s auroras are far from its rotational poles.
The ground-breaking detection of Neptune’s auroras will help us understand how Neptune’s magnetic field interacts with particles that stream out from the Sun to the distant reaches of our solar system, a totally new window in ice giant atmospheric science.
From the Webb observations, the team also measured the temperature of the top of Neptune’s atmosphere for the first time since Voyager 2’s flyby. The results hint at why Neptune’s auroras remained hidden from astronomers for so long.
“I was astonished — Neptune’s upper atmosphere has cooled by several hundreds of degrees,” Melin said. “In fact, the temperature in 2023 was just over half of that in 1989.”
Through the years, astronomers have predicted the intensity of Neptune’s auroras based on the temperature recorded by Voyager 2. A substantially colder temperature would result in much fainter auroras. This cold temperature is likely the reason that Neptune’s auroras have remained undetected for so long. The dramatic cooling also suggests that this region of the atmosphere can change greatly even though the planet sits over 30 times farther from the Sun compared to Earth.
Equipped with these new findings, astronomers now hope to study Neptune with Webb over a full solar cycle, an 11-year period of activity driven by the Sun’s magnetic field. Results could provide insights into the origin of Neptune’s bizarre magnetic field, and even explain why it’s so tilted.
“As we look ahead and dream of future missions to Uranus and Neptune, we now know how important it will be to have instruments tuned to the wavelengths of infrared light to continue to study the auroras,” added Leigh Fletcher of Leicester University, co-author on the paper. “This observatory has finally opened the window onto this last, previously hidden ionosphere of the giant planets.”
These observations, led by Fletcher, were taken as part of Hammel’s Guaranteed Time Observation program 1249. The team’s results have been published in Nature Astronomy.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
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Media ContactsLaura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Hannah Braun- hbraun@stsci.edu
Space Telescope Science Institute, Baltimore, Maryland
Christine Pulliam – cpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Henrik Melin (Northumbria University)
Related InformationView more: Webb images of Neptune
Watch: Visualization of Neptune’s tilted magnetic axis
Learn more : about Neptune
Related For Kids En Español Keep Exploring Related Topics James Webb Space TelescopeShare Details Last Updated Mar 25, 2025 Editor Stephen Sabia Contact Laura Betz laura.e.betz@nasa.gov Related Terms
Spectacular Northern Lights shine across the UK
NASA’s Lunar Reconnaissance Orbiter Views IM-2 on Moon’s Surface
1 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)NASA’s LRO (Lunar Reconnaissance Orbiter) imaged Intuitive Machines’ IM-2 on the Moon’s surface on March 7, just under 24 hours after the spacecraft landed.
Later that day Intuitive Machines called an early end of mission for IM-2, which carried NASA technology demonstrations as part of the agency’s CLPS (Commercial Lunar Payload Services) initiative and Artemis campaign.
The Intuitive Machines IM-2 Athena lander, indicated here with a white arrow, reached the surface of the Moon on March 6, 2025, near the center of Mons Mouton. NASA’s Lunar Reconnaissance Orbiter (LRO) imaged the site at 12:54 p.m. EST on March 7.NASA/Goddard/Arizona State University
The IM-2 mission lander is located closer to the Moon’s South Pole than any previous lunar lander.
LRO is managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, for the Science Mission Directorate at NASA Headquarters in Washington. Launched on June 18, 2009, LRO has collected a treasure trove of data with its seven powerful instruments, making an invaluable contribution to our knowledge about the Moon. NASA is returning to the Moon with commercial and international partners to expand human presence in space and bring back new knowledge and opportunities.
More on this story from Arizona State University’s LRO Camera website
Media Contact:
Nancy N. Jones
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Glowing spiral in UK sky believed to be caused by SpaceX launch
The Falcon 9 is a reusable rocket. After launching into space, it releases what is called its payload - whatever it is carrying, such as a satellite, to complete its mission - which continues its journey into space.
The rocket then turns back around towards Earth. As it does, it ejects any leftover fuel, which freezes instantly due to the altitude in a spiral pattern caused by the rocket's movement.
Light is then reflected off the frozen fuel, making it visible on Earth.
The glowing swirl was photographed in England and Wales, and was also seen in parts of Europe.
Astronomer Allan Trow said it had appeared above Wales's Bannau Brycheiniog national park at around 20:00.
He said he had seen the phenomenon before around four years ago.
"But these are pretty rare," he told the BBC, and agreed the rocket was its likely source.
Stockport-based Sonia was already out with her telescope when she saw "a swirling galaxy that was moving across the sky".
People living almost 200 miles (321km) away also spotted the unusual glow.
Steven Hall was taking his bins out from his home in rural Suffolk when he saw what looked like "a huge Catherine wheel which appeared to have its own atmosphere around it".
He added: "It did pass my mind, is this an unexplained, unidentified flying object?"
SpaceX said on X the launch was carried out on behalf of the US government National Reconnaissance Office mission. The Kennedy Space Center also said on X the launch was a classified mission for that office.
NASA’s Webb Telescope Unmasks True Nature of the Cosmic Tornado
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Craving an ice cream sundae with a cherry on top? This random alignment of Herbig-Haro 49/50 — a frothy-looking outflow from a nearby protostar — with a multi-hued spiral galaxy may do the trick. This new composite image combining observations from NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) provides a high-resolution view to explore the exquisite details of this bubbling activity.
Herbig-Haro objects are outflows produced by jets launched from a nearby, forming star. The outflows, which can extend for light-years, plow into a denser region of material. This creates shock waves, heating the material to higher temperatures. The material then cools by emitting light at visible and infrared wavelengths.
Image A:Herbig-Haro 49/50 (NIRCam and MIRI Image) NASA’s James Webb Space Telescope observed Herbig-Haro 49/50, an outflow from a nearby still-forming star, in high-resolution near- and mid-infrared light. The intricate features of the outflow, represented in reddish-orange color, provide detailed clues about how young stars form and how their jet activity affects the environment around them. Like the wake of a speeding boat, the bow shocks in this image have an arc-like appearance as the fast-moving jet from the young star slams into the surrounding dust and gas. A chance alignment in this direction of the sky provides a beautiful juxtaposition of this nearby Herbig-Haro object with a more distant spiral galaxy in the background. Herbig-Haro 49/50 gives researchers insights into the early phases of the formation of low-mass stars similar to our own Sun. In this Webb image, blue represents light at 2.0-microns (F200W), cyan represents light at 3.3-microns (F335M), green is 4.4-microns (F444W), orange is 4.7-microns (F470N), and red is 7.7-microns (F770W).NASA, ESA, CSA, STScI
When NASA’s retired Spitzer Space Telescope observed it in 2006, scientists nicknamed Herbig-Haro 49/50 (HH 49/50) the “Cosmic Tornado” for its helical appearance, but they were uncertain about the nature of the fuzzy object at the tip of the “tornado.” With its higher imaging resolution, Webb provides a different visual impression of HH 49/50 by revealing fine features of the shocked regions in the outflow, uncovering the fuzzy object to be a distant spiral galaxy, and displaying a sea of distant background galaxies.
Image B:Herbig-Haro 49/50 (Spitzer and Webb Images Side-by-Side) This side-by-side comparison shows a Spitzer Space Telescope Infrared Array Camera image of HH 49/50 (left) versus a Webb image of the same object (right) using the NIRCam (Near-infrared Camera) instrument and MIRI (Mid-infrared Instrument). The Webb image shows intricate details of the heated gas and dust as the protostellar jet slams into the material. Webb also resolves the “fuzzy” object located at the tip of the outflow into a distant spiral galaxy. The Spitzer image shows 3.6-micron light in blue, the 4.5-micron in green, and the 8.0-micron in red (IRAC1, IRAC2, IRAC4). In the Webb image, blue represents light at 2.0-microns (F200W), cyan represents light at 3.3-microns (F335M), green is 4.4-microns (F444W), orange is 4.7-microns (F470N), and red is 7.7-microns (F770W).NASA, ESA, CSA, STScI, NASA-JPL, SSC
HH 49/50 is located in the Chamaeleon I Cloud complex , one of the nearest active star formation regions in our Milky Way, which is creating numerous low-mass stars similar to our Sun. This cloud complex is likely similar to the environment that our Sun formed in. Past observations of this region show that the HH 49/50 outflow is moving away from us at speeds of 60-190 miles per second (100-300 kilometers per second) and is just one feature of a larger outflow.
Webb’s NIRCam and MIRI observations of HH 49/50 trace the location of glowing hydrogen molecules, carbon monoxide molecules, and energized grains of dust, represented in orange and red, as the protostellar jet slams into the region. Webb’s observations probe details on small spatial scales that will help astronomers to model the properties of the jet and understand how it is affecting the surrounding material.
The arc-shaped features in HH 49/50, similar to a water wake created by a speeding boat, point back to the source of this outflow. Based on past observations, scientists suspect that a protostar known as Cederblad 110 IRS4 is a plausible driver of the jet activity. Located roughly 1.5 light-years away from HH 49/50 (off the lower right corner of the Webb image), CED 110 IRS4 is a Class I protostar. Class I protostars are young objects (tens of thousands to a million years old) in the prime time of gaining mass. They usually have a discernable disk of material surrounding them that is still falling onto the protostar. Scientists recently used Webb’s NIRCam and MIRI observations to study this protostar and obtain an inventory of the icy composition of its environment.
These detailed Webb images of the arcs in HH 49/50 can more precisely pinpoint the direction to the jet source, but not every arc points back in the same direction. For example, there is an unusual outcrop feature (at the top right of the main outflow) which could be another chance superposition of a different outflow, related to the slow precession of the intermittent jet source. Alternatively, this feature could be a result of the main outflow breaking apart.
Video Caption:This visualization examines the three-dimensional structure of Herbig-Haro 49/50 (HH 49/50) as seen in near- and mid-infrared light by the James Webb Space Telescope. HH 49/50 is an outflow produced by the jet of a nearby still-forming star in the Chamaeleon I Cloud complex, one of the nearest active star formation regions in our Milky Way. At a distance of 625 light-years from Earth, this new composite infrared image (using data from program 6558, PI: M. Garcia Marin) allows researchers to examine its details on small spatial scales like never before.
Visualization Credit: NASA, ESA, CSA, J. DePasquale (STScI), L. Hustak (STScI), G. Bacon (STScI), R. Crawford (STScI), D. Kirshenblat (STScI), C. Nieves (STScI), A. Pagan (STScI), F. Summers (STScI).
The galaxy that appears by happenstance at the tip of HH 49/50 is a much more distant, face-on spiral galaxy. It has a prominent central bulge represented in blue that shows the location of older stars. The bulge also shows hints of “side lobes” suggesting that this could be a barred-spiral galaxy. Reddish clumps within the spiral arms show the locations of warm dust and groups of forming stars. The galaxy even displays evacuated bubbles in these dusty regions, similar to nearby galaxies observed by Webb as part of the PHANGS program.
Webb has captured these two unassociated objects in a lucky alignment. Over thousands of years, the edge of HH 49/50 will move outwards and eventually appear to cover up the distant galaxy.
Want more? Take a closer look at the image, “fly through” it in a visualization, and compare Webb’s image to the Spitzer Space Telescope’s.
Herbig-Haro 49/50 is located about 625 light-years from Earth in the constellation Chamaeleon.
The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.
DownloadsClick any image to open a larger version.
View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
Media ContactsLaura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Quyen Hart – qhart@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Christine Pulliam – cpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Images – Webb images of other protostar outflows – L483, HH 46/47, and HH 211
Animation Video – “Exploring Star and Planet Formation”
Interactive – Explore the jets emitted by young stars in multiple wavelengths: ViewSpace Interactive
Article – Read more about Herbig-Haro objects
Related For Kids En Español Keep Exploring Related Topics James Webb Space Telescope Share Details Last Updated Mar 24, 2025 EditorStephen SabiaContactLaura Betzlaura.e.betz@nasa.gov Related TermsWinds on an ultrahot planet challenge climate models
Nature, Published online: 24 March 2025; doi:10.1038/d41586-025-00809-6
The ultrahot exoplanet WASP‑121 b has strong winds that transport material in different directions depending on the altitude in the planet’s atmosphere. High-resolution observations have mapped these winds for the first time, challenging the current understanding of atmospheric dynamics.The expanding Universe — do ongoing tensions leave room for new physics?
Nature, Published online: 24 March 2025; doi:10.1038/d41586-025-00896-5
One century after Edwin Hubble revealed his astonishing discovery of a cosmos beyond the Milky Way, the most precise measurements still can’t agree on how fast galaxies are moving.NASA has made the first radio telescope observations on the moon
The Moon is nearly as old as Earth
Hubble Sees a Spiral and a Star
This NASA/ESA Hubble Space Telescope image features a sparkling spiral galaxy paired with a prominent star, both in the constellation Virgo. While the galaxy and the star appear to be close to one another, even overlapping, they’re actually a great distance apart. The star, marked with four long diffraction spikes, is in our own galaxy. It’s just 7,109 light-years away from Earth. The galaxy, named NGC 4900, lies about 45 million light-years from Earth.
This image combines data from two of Hubble’s instruments: the Advanced Camera for Surveys, installed in 2002 and still in operation today, and the older Wide Field and Planetary Camera 2, which was in use from 1993 to 2009. The data used here were taken more than 20 years apart for two different observing programs — a real testament to Hubble’s long scientific lifetime!
Both programs aimed to understand the demise of massive stars. In one, researchers studied the sites of past supernovae, aiming to estimate the masses of the stars that exploded and investigate how supernovae interact with their surroundings. They selected NGC 4900 for the study because it hosted a supernova named SN 1999br.
In the other program, researchers laid the groundwork for studying future supernovae by collecting images of more than 150 nearby galaxies. When researchers detect a supernova in one of these galaxies, they can refer to these images, examining the star at the location of the supernova. Identifying a supernova progenitor star in pre-explosion images gives valuable information about how, when, and why supernovae occur.
Image credit: ESA/Hubble & NASA, S. J. Smartt, C. Kilpatrick
Author Correction: Observation of an ultra-high-energy cosmic neutrino with KM3NeT
Nature, Published online: 20 March 2025; doi:10.1038/s41586-025-08836-z
Author Correction: Observation of an ultra-high-energy cosmic neutrino with KM3NeTDark Energy experiment challenges Einstein's theory of Universe
Can Earth’s rotation generate power? Physicists divided over controversial claim
Nature, Published online: 19 March 2025; doi:10.1038/d41586-025-00847-0
Experiments suggest that an unusual magnetic material can help harness energy from the planet’s rotation. But not everyone is convinced.Is dark energy getting weaker? Fresh data bolster shock finding
Nature, Published online: 19 March 2025; doi:10.1038/d41586-025-00837-2
Physicists had long assumed that the elusive force has constant strength. But the latest results from a project to map the Universe’s expansion challenge this idea.Dark energy isn't what we thought – and that may transform the cosmos
Is our cosmos just a membrane on the edge of a far stranger reality?
Cleaning up space: how satellites and telescopes can live together
Nature, Published online: 18 March 2025; doi:10.1038/d41586-025-00788-8
Satellites connect people around the world but they also interfere with astronomers’ views of the cosmos. There are ways to reduce these tensions.Swarms of satellites are harming astronomy. Here’s how researchers are fighting back
Nature, Published online: 18 March 2025; doi:10.1038/d41586-025-00792-y
SpaceX and other companies plan to launch tens of thousands of satellites, which could mar astronomical observations and pollute the atmosphere.Light pollution threatens fleet of world-class telescopes in Atacama Desert
Nature, Published online: 19 March 2025; doi:10.1038/d41586-025-00397-5
The effects of a proposed green-energy facility in Chile could be devastating for some of the most powerful instruments available to astronomers.