A hummingbird shape in satellite data from NISAR is actually a mountaintop spotted in Antarctica. (Image credit: NASA/JPL-Caltech)
In satellite data captured over Antarctica, what appears to be a beautiful, colorful hummingbird emerges from the crest of a mountaintop.
What is it?
While there are no hummingbirds flying around Antarctica, we can see what looks like a small, purple bird in a new satellite image of an Antarctic mountain. The dark belly of this "bird" at the center of this image is actually the top of the mountain Nunatak Zaterjavshijsja in East Antarctica.
What looks like a bird's tail is a stream of ice flowing northeast all the way out to the ocean, and what appear to be feathers splaying outward from the mountaintop are actually crevasses down the mountain. These crevasses are formed by a glacier fracturing the mountain's surface as it flows in the icy current toward the ocean.
This view was captured by radar instruments onboard the satellite NISAR (NASA-ISRO Synthetic Aperture Radar) that launched as a collaboration between NASA and ISRO (Indian Space Research Organisation). The director of NASA's Earth Science Division called NISAR "the most sophisticated radar we've ever built" in a pre-launch briefing last year.
Why is it incredible?
At first glance, this image is puzzling. What could it possibly be? Its bold colors and sharp lines evoke almost alien qualities. But the strange beauty of the shapes and colors in this satellite image reveal important information about glacier movements on the mountain.
"First, it's a beautiful image, with rich details of features that provide insights to how the glacier is moving. Then, because radar can often see through snow and deep into the ice, NISAR can observe fundamentally different properties of Antarctic ice than can be seen in optical imagery," Seongsu Jeong, the signal analysis engineer who produced the image at NASA's Jet Propulsion Laboratory, said in a statement. "With NISAR we're seeing what's hidden beneath the surface."
And now anyone can explore NISAR's data. Earlier this week, on July 20, NISAR started making the data from its radar instruments public. Moving forward, mission teams will be rolling out this data so researchers everywhere can use it to study and protect our ever-changing planet.
Paleontologists now know that many of the dinosaurs didn't disappear but instead evolved into modern birds, and new research suggests that "cosmic dinosaurs" observed by the James Webb Space Telescope (JWST) didn't go extinct either. Rather, they may have evolved into familiar sights in the modern universe: vast conglomerations of densely packed stars called "globular clusters."
Little Red Dots became quite the puzzle for astronomers in 2022, when the JWST began to routinely spot them in abundance around 600 million years after the Big Bang. That is because these objects seemingly disappear before the cosmos gets to around 2 billion years old.
Astronomers have proposed many different explanations for Little Red Dots, including the suggestion that they could be "black hole stars," or black holes wrapped in vast shrouds of dense gas and dust. This team theorizes that a forming globular cluster with a supermassive star, a hypothetical short-lived stellar body with between 1,000 and 10,000 times the mass of the sun, would also look a lot like a Little Red Dot at its heart.
"These may not be just a strange new JWST population with no connection to the universe around us today," team leader John Chisholm of the University of Texas Austin said in a statement. "Instead, Little Red Dots may persist past the early universe, evolving into something relatively familiar.
"Little Red Dots could be galaxies, they could involve black holes, or they could be something even more unexpected. Our work shows that forming globular clusters with supermassive stars should be part of that conversation."
An unfamiliar side to a familar sight
Globular clusters are generally seen in large galaxies and are densely packed with up to many millions of ancient stars. Our galaxy, the Milky Way, is host to at least 150 globular clusters, and though familiar, astronomers still aren't quite sure how they form.
"We usually see them [globular clusters] after billions of years of evolution, at a time when their massive stars are gone, their gas has been cleared out, and dynamical processes have changed their masses and structures," team member Danielle Berg of UT Austin said in the statement. "That makes it very hard to reconstruct the original conditions they formed in."
It is thought that the stars in globular clusters all formed at the same time in the early universe. However, at this time the cosmos should only have had hydrogen, helium and a smattering of heavier elements (which astronomers call "metals") available for star construction. Yet, many stars in globular clusters are strangely abundant in helium and metals like nitrogen, sodium and aluminum, while lacking the expected levels of carbon, oxygen and magnesium.
"This specific pattern indicates nuclear fusion at very high temperatures, much higher than in the cores of even massive normal stars," team member Mike Boylan-Kolchin of UT Austin said in the statement. "A supermassive star is precisely the kind of environment that could produce this combination."
Globular cluster NGC 6638, as seen by the Hubble Space Telescope. (Image credit: ESA/Hubble & NASA, R. Cohen)
Supermassive stars capable of generating this kind of heat would form in the dense environments of early globular clusters in which stellar collisions and mergers would be expected to occur over and over again. The resultant supermassive stars would be short-lived, lasting just around 1 million years (remember the sun is middle-aged at 4.6 billion years old) — but this would be sufficient time to forge the elements needed to explain the peculiar chemistry of globular clusters.
When these supermassive stars die in supernova explosions, the elements they forged would be blasted out to become the building blocks of the next generation of stars. This would provide the stars of modern globular clusters with their unusual chemical fingerprints.
"In our model, the supermassive star that helps make the object look like a Little Red Dot would live for only a short time," Chisholm continued. "Once that star dies, the object may no longer look like a Little Red Dot, even if the cluster itself survives billions of years."
Just some of the "little red dot" galaxies discovered by the JWST. (Image credit: NASA, ESA, CSA, STScI, Dale Kocevski (Colby College))
Strange chemistry isn't the only thing linking early globular clusters with Little Red Dots, however. Not only does the team propose that the distribution of Little Red Dots in the early universe matches the distribution of modern globular clusters, but they also say models of Little Red Dot evolution show that their estimated masses could easily lead to the masses of globular clusters seen in the recent universe.
There is also the issue of timing. Little Red Dots appear around 600 million years after the Big Bang, and that is also the time that scientists estimate that globular clusters would have begun to form.
"There's no single smoking gun at this point that says Little Red Dots are globular clusters, but it would explain a lot of diverse and surprising observations," said Boylan-Kolchin.
This study is currently available to view as a pre-print on the paper repository arXiv.
A near-Earth object that astronomers believed was an asteroid for nearly three decades has been unmasked as a faint, active comet, revealing a case of cosmic mistaken identity that could help improve planetary defense.
The object, known since its discovery in 1998 as 1998 SH2, appeared to be an ordinary asteroid. It follows a 4.5-year orbit around the sun and showed no obvious signs of cometary activity, such as the glowing coma or tail produced when sunlight vaporizes surface ice.
However, during a close pass about 2 million miles (3 million kilometers) from Earth in August 2025, researchers using NASA's Deep Space Network planetary radar system noticed something unexpected: The object wasn't where orbital predictions said it should be, according to a statement from the space agency. That discrepancy prompted scientists to take a closer look, and what they found surprised them.
Using decades of precision optical astrometry — measurements of the object's position against background stars — researchers found that gravity alone couldn't explain its irregular motion. Instead, they detected tiny nongravitational forces consistent with jets of gas escaping from the object's surface as hidden ice warmed in sunlight.
"After we measured the nongravitational perturbations affecting the motion of 1998 SH2 and recognized they weren't compatible with the object being an asteroid, we suspected the object could be an active comet," Davide Farnocchia, lead author of the study and navigation engineer with NASA's Center for Near-Earth Object Studies at the Jet Propulsion Laboratory, said in the statement.
To test the idea, the team observed the object with the European Southern Observatory's Very Large Telescope in Chile and the Canada-France-Hawaii Telescope atop Mauna Kea. The observations revealed a faint but unmistakable comet tail, confirming the object's true identity.
The discovery earned 1998 SH2 a second designation: P/1998 SH2, officially recognizing it as a comet. Beyond solving the mystery, the finding has important implications for planetary defense.
Unlike rocky asteroids, comets can subtly change course as gas escaping from their surfaces acts like tiny thrusters. Identifying those nongravitational forces allows scientists to more accurately predict an object's future orbit and assess any potential impact risk.
"This work shows the importance of continuously tracking near-Earth objects," Farnocchia said in the statement. "Because of outgassing, the motion of comets is more significantly perturbed than that of asteroids.
"Detecting these perturbations can be an important diagnostic tool for planetary defense that will help understand which objects may be comets rather than asteroids, how their orbits evolve, and how that influences their Earth impact risks."
The study also suggests that 1998 SH2 may not be unique. The researchers noted that analyzing the motions of near-Earth objects with increasingly precise astrometry could reveal more hidden comets that have long been classified as asteroids because they lack obvious tails or glowing comas.
As astronomers continue to monitor the growing population of near-Earth objects, subtle orbital changes may prove just as revealing as spectacular comet tails, uncovering more examples of cosmic mistaken identity while helping scientists better understand which objects pose potential threats to Earth.
Their findings were published July 10 in the journal Nature Astronomy.
The launch of NASA's next super telescope, the Nancy Grace Roman Space Telescope (Roman), may mean there is nowhere left for violent black holes to hide.
In fact, these cosmic cannibals may not even be able to hide from Roman at "cosmic noon," a period of the universe's history that occurred around 11 billion to 12 billion years ago. The study of these gory stellar events so early in the history of the universe could help reveal how supermassive black holes grew so big, so rapidly.
Occurrences of black holesripping apart stars are called tidal disruption events (TDEs), and they happen when an unfortunate star's orbit brings it too close to the immense gravitational influence of a supermassive black hole. This simultaneously squashes and squeezes the star in a process called "spaghettification," with plasma pasta wrapping around the black hole and being fed gradually to it.
Because supermassive black holes are wrapped in a one-way, light-trapping boundary called an event horizon, the only way to study them is when they are actively consuming surrounding matter. Such matter swirls around them in what are known as accretion disks.
However, lighter supermassive black holes aren't ravenous feeders, making them harder to investigate. That is, until a star gets too close and is shredded in an incredibly bright TDE that can outshine the combined light of every star in the supermassive black hole's host galaxy. TDEs are more common to supermassive black holes with masses of about 100,000 to 100 million suns, because supermassive black holes with masses over 1 billion solar masses tend to immediately swallow their stellar snacks.
Previous research has suggested TDEs wouldn't be common in the early universe, because the first supermassive black holes wouldn't even have a mass of 100,000 times that of the sun and thus wouldn't shred stars. However, a new study has reassessed the frequency of TDEs around 1 billion to 2 billion years after the Big Bang, finding they could be more common than previously estimated. Especially during the crowded conditions found during cosmic noon.
Set to launch on Aug. 30, 2026, scientists are hoping Roman's High-Latitude Time-Domain Survey, which will repeatedly revisit a region of the sky equivalent to 90 full moons, will be a powerful tool in the hunt for TDEs in the early universe and their subsequent study. This team estimated that Rubin will detect thousands to tens of thousands of TDEs each year, with 100s dating back to cosmic noon.
"The Roman Space Telescope is going to be transformative for transient science [transients are astronomical events that light up the sky then fade away]," research team leader Mitchell Karmen of the Johns Hopkins University said in a statement. "Thanks to Roman's high sensitivity, we can find multiple tidal disruption events out to greater distances and earlier cosmic times than ever before."
This means Roman is ideally poised to solve a puzzle that has developed since its predecessor, theJames Webb Space Telescope (JWST), began beaming data back to Earth in July 2022.
How could early TDEs solve the puzzle of black hole growth
Supermassive black holes with masses equivalent to millions or even billions of suns are found at the hearts of all large galaxies. When they are seen in the relatively local universe, that isn't so problematic; they have had plenty of time to grow via mergers and feeding.
However, the JWST has been routinely spotting supermassive black holes prior to the universe being even 1 billion years old. That is troubling because these early black holes should have had to undergo at least 1 billion years of mergers and gluttonous feeding to reach supermassive status. Scientists have two prevailing theories as to how this growth may have happened.
The first suggests supermassive black holes grow from "light seeds," beginning with black holes with masses just a few hundred times that of the sun that are born from the death and collapse of massive stars.
Such black holes might weigh up to a few hundred times the mass of the sun. These black holes would then merge over time, as well as consume surrounding gas at an incredible rate that facilitates rapid growth. For this theory to be the right one, every young galaxy would have to harbor a massive black hole at its center.
An illustration shows a direct collapse black hole forming at the heart of an ancient galaxy. (Image credit: Robert Lea (created with Canva))
The second theory suggests early supermassive black holes grew from "heavy seeds" created directly from the collapse of vast clouds of primordial gas and dust. This would allow rapid growth because black holes could begin the whole merger and feeding process before the first stars lived and died.
Should this be the correct pathway, however, the fact that collapse events would be rare would make massive black holes at the heart of cosmic noon galaxies less common.
Because TDEs are common to less massive supermassive black holes, counting their occurrence at cosmic noon could give an indication of the masses of black holes during that epoch — the key to determining between heavy seeds and light seeds.
"Tidal disruption events help us probe the population of light supermassive black holes, which can help us discriminate between these models," Karmen said.
"Just by counting the number of TDEs as a function of redshift [a measure of cosmic distance], you can put meaningful constraints on the population of million-solar-mass black holes. Roman will be transformative in that it can probe tidal disruption events out to greater distances, so you can look at how the rate of TDEs evolves over time," team member Suvi Gezari, an associate professor of astronomy at the University of Maryland, said. “Just like the JWST has transformed our understanding of distant, high-redshift [very distant] galaxies, Roman is poised to transform our understanding of high-redshift transients."
Since the discovery of the first world beyond the solar system in the 1990s, astronomers have become adept at spotting extrasolar planets, or exoplanets. But while NASA's exoplanet catalog has burgeoned to over 6,000 confirmed entries, moons around these worlds, known as exomoons, have proved elusive.
In fact, we have failed to make a single confirmed discovery of an exomoon despite being certain that just as the planets of the solar system have their own natural satellites, worlds in other star systems must have them too.
Now, this controversial drought of exomoons may have become even more confusing and, frankly, weird. That is because while studying a strange star system called CD-35 2722 with the Very Large Telescope (VLT), astronomers have discovered an object that could be an exomoon, or it could be something that forces us to rethink our very definition of what a "moon" is and what a "planet" is.
The star CD-35 2722 is located around 73 light-years away and has around half the mass of the sun. It is orbited by a "failed star" or brown dwarf. These stellar bodies get their unfortunate nickname because they form like other stars but fail to gather enough mass to trigger the fusion of hydrogen to helium in their cores. In terms of mass, brown dwarfs are more massive than the largest gas giant planets, but smaller than the smallest stars, usually with around 13 to 80 times the mass of Jupiter, or around 0.013 to 0.08 times the mass of the sun.
The newly discovered object in CD-35 2722 is certainly moon-like, but rather than orbiting a planet as the moons in the solar system do, it orbits the system's brown dwarf.
"This system is somewhat hard to define using solar-system-based words like 'planet' and 'moon.' The exosatellite is clearly massive enough to be a planet, but it does not orbit a star, though it orbits an object that orbits a star," team leader Kevin Hoy of the Universidad Diego Portales and the Millennium Nucleus of Young Exoplanets and their Moons (YEMS) in Chile, said in a statement.
"Being the third wheel in this system makes us want to call it a moon, even if it is nothing like the small, rocky moons we have in our system."
The team's research was published on Wednesday (July 22) in the journal Nature.
Erm... It's definitely an exosatellite
The team currently isn't able to definitively claim this object in CD-35 2722 is an exomoon, because that would require really nailing down a new definition of what a moon is.
"The satellite we report is a giant gaseous body orbiting a highly massive companion, itself several times the mass of Jupiter. We have a clear delineation between the planets and the sun in the solar system, so defining things like moons is simple," team member Alice Zurlo of the Universidad Diego Portales said. "In the CD-35 2722 system, where we are blurring the lines between stars, planets, and moons, the whole thing becomes more complicated to describe."
Zurlo and colleagues can, however, confidently claim this is an exosatellite, meaning it is a first-of-its-kind detection no matter what the future holds for its classification.
The Extremely Large Telescope (ELT), currently under construction in Chile, could be integral in the hunt for exomoons and exosatellites. (Image credit: ESO/G. Vecchia)
It is hoped that the Extremely Large Telescope (ELT) currently under construction in Chile, will make a massive impact in the hunt for exomoons, and now, other exosatellites.
Until these objects begin to be uncovered, one thing this discovery re-emphasizes is something that astronomers have been gleefully discovering ever since the first exoplanet was spotted: planetary systems come in a variety of diverse, weird and wonderful forms.
The first-ever photo captured on the surface of Mars, snapped on July 20, 1976 by NASA's Viking 1 lander. (Image credit: NASA/JPL)
You're looking at history. What might seem like a simple black-and-white picture of some rocks is actually the first photograph ever taken on the surface of Mars.
What is it?
Bright and early on the morning of July 20, 1976, NASA's Viking 1 lander touched down on the surface of Mars. This moment 50 years ago marked the first fully successful touchdown on the Red Planet, and, pretty much as soon as it landed, Viking 1 captured the first image of the Martian surface.
The Soviet Union had already made multiple Mars landing attempts, all of them failures to some degree. The nation's Mars 3 lander did manage to survive its landing initially in December 1971, but it lost contact less than two minutes later.
Viking 1 did more than just survive. While its mission tasked the lander with studying the planet for 90 days after landing, it lasted over six years on the planet and made some incredible observations. The Viking 1 lander worked in tandem with an orbiter by the same name, and was soon joined at Mars by Viking 2, another lander/orbiter pair.
Why is it incredible?
It has now been 50 years since Viking 1's historic first, which opened our eyes to the Martian surface. And NASA has kept improving technologies and exploring further on Mars ever since. Agency rovers began scouring the planet's surface in the 1990s, so we have gathered data on the planet's surface for decades upon decades at this point.
But in 1976, no one had ever seen the surface of Mars close up. This view was preceded by science fiction like Ray Bradbury's "The Martian Chronicles," which painted fantastical possibilities about what it might really be like on Mars. With Viking 1's view, we finally got some concrete evidence of the reality on the planet.
In 50 years, our understanding of Mars, our solar system and beyond has grown tremendously. But with each major accomplishment, we can look back at previous milestones such as this to see the stepping stones that paved the way to get us there.
Swelling from a razor-thin crescent into a cratered world before fading back into the darkness, Mars gave NASA's Psyche spacecraft both a spectacular view — and a 1,000-mph boost toward its namesake asteroid.
A new time-lapse video released by NASA, stitched from images taken throughout May, captures the probe's month-long encounter with Mars. On May 15, Psyche swooped within 2,864 miles (4,609 kilometers) of the surface, using the planet's gravity to boost its speed and adjust its trajectory toward asteroid Psyche, a metal-rich world in the main asteroid belt between Mars and Jupiter that the spacecraft is scheduled to reach in 2029.
"This gravity assist was years in the making, and the navigation team nailed it — Psyche flew by Mars on exactly the trajectory we needed to set us on a path to rendezvous with the asteroid in the summer of 2029," Bob Mase, Psyche's project manager at NASA's Jet Propulsion Laboratory in California, said in a statement.
A screenshot from the timelapse, showing Psyche approaching a crescent Mars. (Image credit: NASA/JPL-Caltech/ASU/True Story Films)
Approaching from a steep or what scientists call a "high phase" angle relative to the sun, Psyche initially caught Mars as a slender crescent with just 4 percent of its disk illuminated and its thin atmosphere glowing in scattered sunlight, Hannah Zigo, a Psyche team member at the Arizona State University, said in a NASA video accompanying the statement.
As the spacecraft closed in, the video follows Mars steadily expanding to reveal numerous craters puncturing its surface, the ancient double-ringed Huygens crater and the south polar ice cap before receding in the spacecraft's rearview.
The flyby served a dual purpose. By aiming Psyche's suite of instruments at a well-studied world, engineers say they calibrated and validated the spacecraft's scientific payload ahead of its 2029 destination.
"We didn't anticipate big discoveries, given how extensively the planet has been studied," Lindy Elkins-Tanton, principal investigator for the Psyche mission at the University of California, Berkeley, said in the statement, "but we did complement Mars science with the data we collected through Psyche's unique perspective."
All three of the spacecraft's science instruments performed as expected, according to NASA. Its gamma-ray and neutron spectrometer, designed to determine the asteroid's elemental makeup, detected the predicted surge of escaping neutrons during closest approach, confirming its operational readiness.
The mission's magnetometer, which will search for evidence that asteroid Psyche is the metallic core of an early planetesimal, recorded its first magnetic signature from a planetary body since its launch in 2023, detecting the bow shock where the solar wind meets Mars' magnetic environment.
Psyche's twin multispectral cameras also passed their calibration tests, capturing the frames for the time-lapse while spotting Mars' tiny moons, Phobos and Deimos, from a distance, the NASA statement read.
Spotting the moons served as "a practice for the satellite search that we'll use at the asteroid Psyche to look for any moonlets there," Jim Bell, a planetary scientist at Arizona State University who leads the multispectral imager instrument team, said in the statement.
With Mars in its rearview and its instruments fully vetted, Psyche remains locked on course for its summer 2029 rendezvous with the metal asteroid.
"The spacecraft is in great shape, and we're on schedule to resume sustained thrusting with the solar-electric propulsion system later this fall," Mase said.
Using the James Webb Space Telescope (JWST), astronomers have discovered the secrets of early galaxies that pumped the infant cosmos full of dust, which would become vital for the birth of new stars and the growth of galaxies.
However, while the JWST is powerful enough to see many of these early galaxies, it is still limited when it comes to delving into them in great detail. So, the team at the heart of this research worked around this by studying a much closer and more modern galaxy with many characteristics that resemble the universe's first galaxies.
In lieu of being able to study the processes that occurred in the early universe that allowed galaxies to be seeded with "metals, (the term astronomers use to describe elements heavier than hydrogen and helium), the researchers turned their attention to a dwarf galaxy just 4.6 million light-years away.
"Directly studying the galaxies that populated the early universe is still very difficult, which is why observing a nearby galaxy like Sextans A, which presents similar chemical conditions, offers us a precious opportunity to understand how the first generations of stars evolved and what role they played in transforming the interstellar medium," team leader Claudio Gavetti of the National Institute for Astrophysics (INAF) said in a statement.
How does Sextans A impersonate ancient galaxies?
The early universe was a pretty dull place in terms of chemistry. That is because it was dominated by the lightest element, hydrogen, with some helium and a tiny smattering of heavy elements, or metals. That means that the first generation of stars, so-called POP III stars, were correspondingly metal-poor.
During their lives, however, POP III stars fused hydrogen and helium in their cores to forge heavier elements. When these original stars reached the ends of their lives, they exploded in supernova explosions that dispersed these metals into the interstellar medium, the vast clouds of dust and gas between stars.
Eventually, dense and cool patches in these vast clouds collapsed under their own gravity, birthing the next generation of stars, POP II stars, which, thanks to the supernova deaths of their predecessors, were richer in metals.
The dwarf galaxy Sextans A observed by the James Webb Space Telescope. (Image credit: NASA, ESA, CSA, STScI, Janice Lee (NOIRLab). Image processing: Alyssa Pagan (STScI).)
Our own star, the sun, is classed as a POP I star, meaning it is even richer in metals than these second-generation stars. However, not all modern galaxies are so metal-rich; this is especially true for dwarf galaxies like Sextans A, even though it lies at the outer edge of our cosmic backyard, known as the "local group."
Sextans A is so metal-poor that it is estimated to contain only between 1% and 7% of the heavy elements found in the sun. That makes it a great proxy for the study of metal-poor early galaxies.
Using the JWST's NIRCam (Near-InfraRed Camera) and MIRI (Mid-Infrared Instrument) instruments, Gavetti and colleagues obtained high-resolution observations of Sextans A that allowed them to map the dwarf galaxy's entire population of stars during an evolutionary phase known as the "asymptotic red giant branch."
This phase occurs when stars larger than the sun exhaust helium in their cores, creating an inert carbon heart, but nuclear fusion continues in outer alternating helium- and hydrogen-burning layers. These stars "puff out" as a result of this and can undergo thousandfold increases in brightness.
An image of the galaxy Sextans A where Red indicates the infrared emission of dust, blue the emission of atomic hydrogen gas, and green the far-ultraviolet emission created by newly formed stars. (Image credit: Yong Shi)
The team's findings revealed that around 90% of the asymptotic red giant branch stars they studied were not surrounded by envelopes of dust. However, around 20 or so of these stars were embedded in thick dust shells. They also found that these "dust factories" formed between 2 billion and 3 billion years ago from stars with an initial mass about 1.5 times the mass of the sun.
This research is a leap forward in understanding which stars in the early universe were most likely to create the metal dust that would have enriched the next generations of stars. That means it helps paint a complete picture of how the universe as we see it today took shape.
The scientists behind this study say that this type of research would have been impossible before the launch of Webb.
"The JWST allows us to observe in unprecedented detail environments that until a few years ago were beyond our reach," team member Flavia Dell'Agli of the INAF. "The value of these data lies not only in the images, but in the ability to compare them with theoretical models and verify how correctly they describe the evolution of stars."
For the first time, scientists may have discovered a binary system—like the twin suns of the fictional planet Tatooine in "Star Wars"—where both stars exploded as supernovas, a new study finds.
Although Earth may orbit around a single star, more than half of all stars are in systems where two or more suns orbit each other. "When it comes to massive stars, the percentage in multiple systems are even higher," study lead author Miltiadis Michailidis, a postdoctoral fellow at Stanford University in California, told Space.com.
When massive stars burn all their fuel, they can die in giant explosions known as supernovas. These outbursts can briefly outshine all of the other suns in these stars' galaxies. They often leave behind expanding super-hot clouds of debris known as supernova remnants. Astronomers have detected about 300 such remnants in our galaxy to date.
Given how often massive stars are found in binary systems, "one can expect many pairs of massive stars where both will explode as supernovas," Michailidis noted. "However, this has never been observed, until now."
One reason supernova pairs may have escaped attention is that "if the stars are too close together when they exploded, the resulting supernova remnants may look like that from a single explosion," Michailidis explained. Another is that one star going supernova may propel its partner far enough away to hide the fact they were ever a duo, he added.
In the new study, Michailidis and his colleagues investigated a supernova remnant known as IC 443, located about 6,000 light-years from Earth in the constellation Gemini. IC 443 is also known as the Jellyfish Nebula for how it resembles a jellyfish.
IC 443 is one of the most extensively studied supernova remnants in the galaxy because of how shock waves from the supernova have collided with surrounding clouds of gas and dust to create a set of concentric bubble shells, "much like how a drop of water falling on a lake creates circular waves," Michailidis said. "It is very isolated from its surroundings, without many other objects nearby to complicate its very bright emissions."
The scientists analyzed one of IC 443's much dimmer, long-hidden neighbors, dubbed G189.6+3.3. The German-led ROSAT (Roentgen Satellite) mission first discovered G189.6+3.3 in 1994 via its faint X-ray emissions, and the Russian-German Spektrum Roentgen Gamma (SRG) space observatory later clearly detected shell-like structures within G189.6+3.3, suggesting that it was a supernova remnant.
A composite multiwavelength view of the IC 443 region (with the X-ray emission from IC 443 removed) overlaid with gamma-ray emission above 1 GeV detected by the Fermi Large Area Telescope. (Image credit: NASA Goddard Space Flight Center and M. Michailidis et al. 2026; orange, brown: radio, ESA/Planck and MWISP; yellow: optical, DSS; red: infrared, NASA/WISE; violet: ultraviolet, NASA/Swift; teal: X-rays, SRG/eROSITA; magenta: gamma rays, NASA/DOE/Fermi LAT Collaboration)
In the new study, the researchers analyzed more than 16 years of data from NASA's Fermi Gamma-ray Space Telescope along with earlier X-ray, optical and radio measurements. They discovered signs that both IC 443 and G189.6+3.3 were both smashing into the same interstellar cloud of hydrogen, revealing they were close together in space, with the centers of their explosions about 30 to 50 light-years apart.
The researchers calculated that the chances of randomly encountering two unrelated supernova remnants at this distance from one another "was about one in 1,000," Michailidis said. "This suggests that our discovery is in fact the first known binary-system supernova pair."
The scientists estimated that G189.6+3.3 was older than IC 443, with the parent star of G189.6+3.3 exploding between 20,000 to 110,000 years ago, while IC 443 was created about 8,000 to 9,000 years ago. The original stars may have been 20 or more times the sun's mass.
These new findings can help shed light on how massive binary stars evolve, interact and die. For instance, further analysis of G189.6+3.3 and IC 443 can reveal how much of a kick the former gave the latter when it died, Michailidis said.
The scientists detailed their findings July 21 in the journal Nature Communications.
The James Webb Space Telescope captured this image of a young galaxy cluster, MACS J0553.4-3342. (Image credit: ESA/Webb, NASA & CSA, S. Fujimoto)
A young cluster of galaxies sparkles under a cosmic glow that's 4.4 billion years old. This peek into the past shows the stellar spectacle of a galaxy cluster still forming.
What is it?
The James Webb Space Telescopesnapped this image of the galaxy cluster MACS J0553.4-3342 on July 3 using its near-infrared camera (NIRCam). The glorious, glimmering sight is actually a massive young galaxy cluster forming 4.4 billion years ago. A galaxy cluster is a grouping of galaxies held together by gravity. Galaxy clusters can contain hundreds or even thousands of galaxies and are the largest known structures in the entire universe that are held together in this way.
Why is it incredible?
Because light takes time to travel through space, and because the JWST can look incredibly far out into space, this telescope acts as a sort time machine.
This power isn't unique to the JWST, however. Other telescopes like the Hubble Space Telescope, for instance, have similarly peered back in time through the cosmos and revealed some incredible, ancient sights. However, the JWST's specialized instruments like NIRCam allow the telescope to pick up incredibly faint light from galaxies remarkably far away. This greatly stretches how far back in time we can see.
But the really incredible thing is, you can look back in time yourself — with only your eyes. While JWST can look exceptionally far out into space and can capture the very faint light of ancient galaxies, the light coming from the stars you can see with your bare eyes also had to travel over incredible stretches of time to reach you. Think about this: the light coming from a constellation you love may have traveled across millions of light-years to get to your eyes.
