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“These mysterious objects are candidate galaxies in the early universe, meaning they could be very early galaxies,” said Haojing Yan, an astronomy professor in Mizzou’s College of Arts and Science and co-author on the study. “If even a few of these objects turn out to be what we think they are, our discovery could challenge current ideas about how galaxies formed in the early universe — the period when the first stars and galaxies began to take shape.”

But identifying objects in space doesn’t happen in an instant. It takes a careful step-by-step process to confirm their nature, combining advanced technology, detailed analysis and a bit of cosmic detective work.

Step 1: Spotting the first clues

Mizzou’s researchers started by using two of JWST’s powerful infrared cameras: the Near-Infrared Camera and the Mid-Infrared Instrument. Both are specifically designed to detect light from the most distant places in space, which is key when studying the early universe.

Why infrared? Because the farther away an object is, the longer its light has been traveling to reach us.

“As the light from these early galaxies travels through space, it stretches into longer wavelengths — shifting from visible light into infrared,” Yan said. “This stretching is called redshift, and it helps us figure out how far away these galaxies are. The higher the redshift, the farther away the galaxy is from us on Earth, and the closer it is to the beginning of the universe.”

Step 2: The ‘dropout’

To identify each of the 300 early galaxy candidates, Mizzou’s researchers used an established method called the dropout technique.

“It detects high-redshift galaxies by looking for objects that appear in redder wavelengths but vanish in bluer ones — a sign that their light has traveled across vast distances and time,” said Bangzheng “Tom” Sun, a Ph.D. student working with Yan and the lead author of the study. “This phenomenon is indicative of the ‘Lyman Break,’ a spectral feature caused by the absorption of ultraviolet light by neutral hydrogen. As redshift increases, this signature shifts to redder wavelengths.”

Step 3: Estimating the details

While the dropout technique identifies each of the galaxy candidates, the next step is to check whether they could be at “very” high redshifts, Yan said.

“Ideally this would be done using spectroscopy, a technique that spreads light across different wavelengths to identify signatures that would allow an accurate redshift determination,” he said.

But when full spectroscopic data is unavailable, researchers can use a technique called spectral energy distribution fitting. This method gave Sun and Yan a baseline to estimate the redshifts of their galaxy candidates — along with other properties such as age and mass.

In the past, scientists often thought these extremely bright objects weren’t early galaxies, but something else that mimicked them. However, based on their findings, Sun and Yan believe these objects deserve a closer look — and shouldn’t be so quickly ruled out.

“Even if only a few of these objects are confirmed to be in the early universe, they will force us to modify the existing theories of galaxy formation,” Yan said.

Step 4: The final answer

The final test will use spectroscopy — the gold standard — to confirm the team’s findings.

Spectroscopy breaks light into different wavelengths, like how a prism splits light into a rainbow of colors. Scientists use this technique to reveal a galaxy’s unique fingerprint, which can tell them how old the galaxy is, how it formed and what it’s made of.

“One of our objects is already confirmed by spectroscopy to be an early galaxy,” Sun said. “But this object alone is not enough. We will need to make additional confirmations to say for certain whether current theories are being challenged.”

The study, “On the very bright dropouts selected using the James Webb Space Telescope NIRCam instrument,” was published in The Astrophysical Journal.

“Unlike most nearby planet-forming disks, where water vapor dominates the inner regions, this disk is surprisingly rich in carbon dioxide,” says Jenny Frediani, PhD student at the Department of Astronomy, Stockholm University.

“In fact, water is so scarce in this system that it’s barely detectable — a dramatic contrast to what we typically observe.”

A newly formed star is initially deeply embedded in the gas cloud from which it was formed and creates a disk around itself where planets in turn can be formed. In conventional models of planet formation, pebbles rich in water ice drift from the cold outer disk toward the warmer inner regions, where the rising temperatures cause the ices to sublimate. This process usually results in strong water vapor signatures in the disk’s inner zones. However, in this case, the JWST/MIRI spectrum shows a puzzlingly strong carbon dioxide signature instead.

“This challenges current models of disk chemistry and evolution since the high carbon dioxide levels relative to water cannot be easily explained by standard disk evolution processes,” Jenny Frediani explains.

Arjan Bik, researcher at the Department of Astronomy, Stockholm University, adds, “Such a high abundance of carbon dioxide in the planet-forming zone is unexpected. It points to the possibility that intense ultraviolet radiation — either from the host star or neighbouring massive stars — is reshaping the chemistry of the disk.”

The researchers also detected rare isotopic variants of carbon dioxide, enriched in either carbon-13 or the oxygen isotopes ¹⁷O and ¹⁸O, clearly visible in the JWST data. These isotopologues could offer vital clues to long-standing questions about the unusual isotopic fingerprints found in meteorites and comets — relics of our own Solar System’s formation.

This CO2-rich disk was found in the massive star-forming region NGC 6357, located approximately 1.7 kiloparsecs (about 53 quadrillion kilometers) away. The discovery was made by the eXtreme Ultraviolet Environments (XUE) collaboration, which focuses on how intense radiation fields impact disk chemistry.

Maria-Claudia Ramirez-Tannus from the Max Planck Institute for Astronomy in Heidelberg and lead of the XUE collaboration says that it is an exciting discovery: “It reveals how extreme radiation environments — common in massive star-forming regions — can alter the building blocks of planets. Since most stars and likely most planets form in such regions, understanding these effects is essential for grasping the diversity of planetary atmospheres and their habitability potential.”

Thanks to JWST’s MIRI instrument, astronomers can now observe distant, dust-enshrouded disks with unprecedented detail at infrared wavelengths — providing critical insights into the physical and chemical conditions that govern planet formation. By comparing these intense environments with quieter, more isolated regions, researchers are uncovering the environmental diversity that shapes emerging planetary systems. Astronomers at Stockholm University and Chalmers have helped develop the MIRI instrument which is a camera and a spectrograph that observes mid- to long-wavelength infrared radiation from 5 microns to 28 microns. It also has coronagraphs, specifically designed to observe exoplanets.

The study “XUE: The CO2-rich terrestrial planet-forming region of an externally irradiated Herbig disk” is published in Astronomy & Astrophysics.

Rogue waves are not anomalies but the result of normal ocean dynamics. New data reveals they can be predicted.

On January 1, 1995, an enormous 80-foot wave struck the Draupner oil platform in the North Sea. The force of the wave bent steel railings and hurled heavy equipment across the deck, but its most significant effect was the evidence it provided. For the first time, scientists were able to record a rogue wave in the open ocean with precise measurements.

“It confirmed what seafarers had described for centuries,” said Francesco Fedele, associate professor Georgia Tech’s School of Civil and Environmental Engineering. “They always talked about these waves that appear suddenly and are very large — but for a long time, we thought this was just a myth.”

Rethinking Rogues

That single measured wave moved rogue waves out of the realm of myth and into science, sparking decades of debate about their origins.

Francesco Fedele, who had long questioned standard theories, led an international research team to explore how these massive waves truly form. Their study, published in Nature’s Scientific Reports, highlighted the importance of their conclusions. The group examined 27,500 wave records spanning 18 years in the North Sea, creating the most extensive dataset ever assembled on the subject.

Each record documented 30 minutes of detailed information, including wave height, frequency, and direction. The results overturned long-standing ideas, showing that rogue waves do not require unusual or “exotic” mechanisms to emerge—only the precise alignment of well-known ocean processes.

Fedele explained, “Rogue waves follow the natural orders of the ocean — not exceptions to them. This is the most definitive, real-world evidence to date.”

Extraordinary Waves, Ordinary Physics

The dominant theory about rogue wave formation has been a phenomenon called modulational instability, a process where small changes in timing and spacing between waves cause energy to concentrate into a single wave. Instead of staying evenly distributed, the wave pattern shifts, causing one wave to suddenly grow much larger than the rest.

Fedele pointed out that modulational instability “is mainly accurate when the waves are confined within channels, like in lab experiments, where energy can only flow in one direction. In the open ocean, though, energy can spread in multiple directions.”

A Deep Dive Into the Data

When Fedele and his colleagues examined the North Sea records, they found no indication that modulational instability played a role in rogue waves. Instead, they concluded that the largest waves arise from the interaction of two well-understood processes:

1. Linear focusing — this occurs when waves moving at different speeds and directions meet at the same point in time and space, combining to create a crest much higher than normal.
2. Second-order bound nonlinearities — natural effects that alter the shape of a wave, sharpening and raising the crest while flattening the trough. This distortion can amplify the height of large waves by 15–20%.

Fedele noted that when these two mechanisms coincide, they generate especially powerful waves. The inherently nonlinear character of ocean motion adds another layer of amplification, driving the waves to grow even larger.

From Failure to Forecast

Fedele stressed that this research has real-world urgency. Rogue waves aren’t just theoretical, they are real, powerful, and a danger to ships and offshore structures. Fedele said many forecasting models still treat rogue waves as unpredictable flukes. “They’re extreme, but they’re explainable,” he said.

Updating those models, he added, is critical. “It’s fundamental for the safety of ship navigation, coastal structures, and oil platforms,” Fedele explained. “They have to be designed to endure these extreme events.”

Fedele’s research is already informing how others think about ocean risk. The National Oceanic and Atmospheric Administration and energy company Chevron use his models to forecast when and where rogue waves are most likely to strike.

Fedele is now using machine learning to comb through decades of wave data, training algorithms to detect the subtle combinations — height, direction, timing — that precede extreme waves. The goal is to give forecasters more accurate tools that predict when a rogue wave could strike.

The lesson from this study is simple: Rogue waves aren’t exceptions to the rules — they’re the result of them. Nature doesn’t need to break its own laws to surprise us. It just needs time, and a rare moment where everything lines up just wrong.

Although ocean waves may seem random, extreme waves like rogues follow a natural recognizable pattern. Each rogue wave carries a kind of “fingerprint” — a structured wave group before and after the peak that reveals how it formed.

“Rogue waves are, simply, a bad day at sea,” Fedele said. “They are extreme events, but they’re part of the ocean’s language. We’re just finally learning how to listen.”

Reference: “Effects of bound-wave asymmetry on North Sea rogue waves” by Sagi Knobler, Mika P. Malila, M. Aziz Tayfun, Dan Liberzon and Francesco Fedele, 1 July 2025, Scientific Reports.
DOI: 10.1038/s41598-025-07156-6

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