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Astronomers Find Rare Star System That Will Trigger a Kilonova

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An artist’s rendition of the binary stay system, called CPD-29 2176.
Illustration: Noir Lab

The universe has no shortage of oddities, and researchers at the National Science Foundation’s NOIRLab have observed another one in the form of a particular binary star system. The system, called CPD-29 2176, will eventually trigger a kilonova, a celestial event in which two neutron stars collide in a massive explosion that forms heavy elements, including gold and platinum.

CPD-29 2176 is located around 11,400 light-years from Earth and was found by researchers using NASA’s Neil Gehrels Swift Observatory. Astronomers then conducted more observations at NOIRLab’s Cerro Tololo Inter-American Observatory in Chile. CPD-29 2176 is home to one neutron star and one massive star that is in the process of going supernova, only to become a second neutron star in the future. Eventually, the two neutron stars will collide, producing a kilonova, an explosion that is thought to produce bursts of gamma rays and large amounts of gold and platinum. The paper documenting the research team’s find is published today in Nature.

“We know that the Milky Way contains at least 100 billion stars and likely hundreds of billions more. This remarkable binary system is essentially a one-in-ten-billion system,” said André-Nicolas Chené in a NOIRLab press release. Chené is a NOIRLab astronomer and an author on the study. “Prior to our study, the estimate was that only one or two such systems should exist in a spiral galaxy like the Milky Way.”

While many stars implode was a powerful supernova when they die, the dying star in CPD-29 2176 is becoming an ultra-stripped supernova. An ultra-stripped supernova lacks the vast amount of force that a typical supernova has, since the dying star has had much of its mass stripped by its companion. The researchers think that the neutron star in the system was also formed with an ultra-stripped supernova and argue that this is the reason that CPD-29 2176 is able to remain as a binary—a typical supernova would have enough power to kick a companion star out of its orbit.

“The current neutron star would have to form without ejecting its companion from the system. An ultra-stripped supernova is the best explanation for why these companion stars are in such a tight orbit,” said lead author Noel D. Richardson, a physics and astronomy professor at Embry-Riddle Aeronautical University, in the NOIRLab release. “To one day create a kilonova, the other star would also need to explode as an ultra-stripped supernova so the two neutron stars could eventually collide and merge.”

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It will take around one million years for the star undergoing ultra-stripped supernova to turn into a neutron star. It is then when the two stars will begin to spiral into each other, eventually resulting in the metal-producing kilonova, according to the research. In these dramatic cosmic endings, we can look forward to the creation of the same elements that make life possible.  

More: Watch Four Planets Spin Around a Star 130 Million Light-Years Away

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Neutron Stars Are Basically Giant Cosmic Pralines, Astrophysicists Say

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An illustration showing the internal workings of heavier (left) and lighter (right) neutron stars, imagined as pralines.
Illustration: Peter Kiefer & Luciano Rezzolla

Astrophysicists modeling the insides of neutron stars have found that the extremely compact objects have different internal structures, depending on their mass. They suggest thinking of the stars as different types of chocolate praline, a delicious treat—but that’s where the similarities end, at least as far as we know.

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Neutron stars are the extraordinarily dense corpses of massive stars that imploded; they’re second only to black holes in terms of their density. Neutron stars are so-named because their gravitational force causes their atoms’ electrons to collapse onto the protons, creating an object that is almost entirely composed of neutrons.

Neutron stars’ gravitational fields are super intense. If a human observer went near one, they’d be torn apart at an atomic level. Their gravitations fields are so strong that a “mountain” on a neutron star would stand less than a millimeter tall.

The recent research team constructed millions of models to try to discern the internal workings of these stars, which are remarkably difficult to study and, as a result, are more the domain of theory than observation.

The researchers found that lighter neutron stars—those with masses about 1.7 times that of our Sun and under—should have soft mantles and stiff cores. Heavier neutron stars have the opposite, according to the team’s findings, which were published today in The Astrophysical Journal Letters.

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Luciano Rezzolla, an astrophysicist at the Institute of Theoretical Physics and who led the research, likened the stars’ structure to chocolate pralines.

“Light stars resemble those chocolates that have a hazelnut in their centre surrounded by soft chocolate, whereas heavy stars can be considered more like those chocolates where a hard layer contains a soft filling,” Rezzolla said in a Goethe University Frankfurt release.

The researchers modeled over a million possible scenarios for neutron star makeup, based on expectations for the star’s mass, pressure, volume, and temperature, as well as astronomical observations of the objects.

Modeling is a crucial means of interrogating neutron stars, because only a few contraptions on Earth—CERN’s Large Hadron Collider and SLAC’s Matter in Extreme Conditions instrument, for two—are capable of mimicking such intense physics.

To determine the consistencies of the stars, the researchers modeled how the speed of sound would travel through the objects. Sound waves are also used to understand the internal structure of planets, as the InSight lander has intrepidly done on Mars.

“What we have shown, by constructing millions of equation of state models (from which the sound speed can be computed), is that maximally massive neutron stars have a lower sound speed in the core region than in their outer layers,” said Christian Ecker, an astrophysicist at Goethe University, in an email to Gizmodo.

“This hints to some material change in their cores, like for example a transition from baryonic to quark matter,” Ecker added.

The researchers also found that all neutron stars are probably about 7.46 miles (12 km) across, regardless of their mass. That measurement is less than half that of a 2020 finding that the typical neutron star was about 13.6 miles (22 km) across. Despite that size, the average neutron star mass is around half a million Earths. There’s dense, and then there’s dense.

While the findings offer some insight about the diversity of neutron stars in terms of their consistency, the researchers did not investigate the stars’ ingredients or how they fit together. (If you’ve gotten this far, neutron stars are not actually made of chocolate.) Some suspect that neutron stars are neutrons all the way down; others believe that the centers of the stars are factories for exotic, hitherto unidentified particles.

But for the most part, these superdense enigmas remain just that. Thankfully, there are observatories set up to collect more direct data. Mergers (i.e. violent collisions) between neutron stars and with black holes can reveal the mass of the involved objects, as well as the nature of neutron star material.

Projects like NICER, NANOGrav, the CHIME radio telescope, and the LIGO and Virgo scientific collaborations are all teaching physicists about neutron star size and structure.

More observational data can be fed into models for better estimates of the stars’ aspects. Ecker added that very massive neutron stars (in the ballpark of two solar masses) would be particularly helpful in better constraining expectations of the physical characteristics of these extreme objects.

With any luck, we may soon get more details of the exact ingredients of these giant cosmic pralines—and how their recipes may differ depending on their size.

More: Extremely Massive Neutron Star May Be the Largest Ever Spotted

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Astrophysicists Discover Closest Black Hole to Earth

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Scientists have discovered a relatively small black hole lurking next to a star in the constellation Ophiuchus, about 1,600 light-years away. It’s now the closest-known back hole to Earth.

Black holes are the densest objects in our universe (sorry, neutron stars). Whether they’re small, stellar-mass black holes or the supermassive ones at the centers of galaxies, the objects have gravitational fields so intense that not even photons of light can escape their event horizons.

The recently discovered black hole—named Gaia BH1—is three times closer to Earth than the previous record holder. Details about its discovery, as well as about the Sun-like star orbiting it, were published this week in the Monthly Notices of the Royal Astronomical Society.

The object was discovered using the Gemini North telescope in Hawaii, part of the International Gemini Observatory, in conjunction with data from the ESA’s Gaia spacecraft. The Gaia data suggested the star’s motion was slightly strange for a single object; it appeared as if the gravity of a massive object were affecting its motion.

Follow-up observations by Gemini North were done to determine the precise orbital period of the companion star, helping the team better estimate the mass of the unseen object.

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“While there have been many claimed detections of systems like this, almost all these discoveries have subsequently been refuted,” said Kareem El-Badry, an astrophysicist at the Center for Astrophysics | Harvard and Smithsonian and the paper’s lead author, in a NOIRLab release. “This is the first unambiguous detection of a Sun-like star in a wide orbit around a stellar-mass black hole in our Galaxy.”

Keep in mind, a single light-year is about 6 trillion miles, so at 1,600 light-years distant the nearby black hole is only relatively nearby. Voyager—humanity’s farthest-traveled space mission—has been zooming away from Earth for nearly 50 years and is just under 15 billion miles away. Alpha Centauri, the closest star system to Earth, is about 4.24 light-years away.

Because light cannot escape black holes, they are most easily seen when they’re surrounded by superheated material they’ve accreted; such is the case for the black hole at the center of Messier 87 and Sagittarius A*, the black hole at the center of the Milky Way. Both of these black holes were imaged by the Event Horizon Telescope Collaboration, thanks to the warm glow of matter that allows you to see where the black hole lurks.

Black holes are much harder to spot when they’re not actively feeding; that is, when they aren’t accreting matter, superheating it, and releasing X-rays in the process. Such is the case with Gaia BH1, which is invisible except for its gravitational effects on the star.

“Our Gemini follow-up observations confirmed beyond reasonable doubt that the binary contains a normal star and at least one dormant black hole,” El-Badry said. “We could find no plausible astrophysical scenario that can explain the observed orbit of the system that doesn’t involve at least one black hole.”

But current models of binary systems involving a black hole and a star don’t explain Gaia BH1’s system. According to NOIRLab, the star that gave way to the black hole in the system would be massive, and it should have engulfed the other (i.e. still-existing) star in the system before the black hole formed.

Observing more black hole binary systems will in time help astrophysicists refine their models of how these systems take shape and evolve. Space observatories like IXPE and NASA’s NICER and NuSTAR will help in these efforts, by scrutinizing the high-energy X-rays emitted by feeding black holes.

More: Black Hole Pukes Up Star Years After Eating It

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Your Ancestors Might Have Seen Red Star Betelgeuse as Yellow

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New research into the star Betelgeuse indicates that the red giant, easily seen in the constellation Orion, may have appeared more orange-yellow in the not-so-distant past.

The research is based on historical sources that described the color of stars in the sky. A recent team looked at 236 stars bright enough that their colors can be seen with the naked eye and sifted through historical records describing the stars, written by the likes of Ptolemy and Tycho Brahe.

Betelgeuse is one of the brightest stars in the sky, located around 600 light-years from Earth in the constellation Orion. Betelgeuse is a red supergiant, with a relatively cool surface temperature and clocking in at about 764 times as large as the Sun. If Betelgeuse were located at the center of our solar system, the four terrestrial planets and Jupiter would be beneath its surface.

The team found that the recorded color of Betelgeuse (we’re allowed to write that more than three times) has changed over the last couple of millennia. Their research is published in the Monthly Notices of the Royal Astronomical Society.

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“There are quite a number of astrophysical problems which can hardly be solved without historical observations,” said Ralph Neuhäuser, an astrophysicist at the University of Jena and lead author of the recent paper, in a university release.

In the work, the team cataloged the descriptions of Betelgeuse by notable astronomers over the last 2,000 years, including Sima Qian in the 2nd century BCE in China, Hyginus and Germanicus in the first century CE in Europe, and Al-Ṣūfī in the 10th century CE in Persia.

The more qualitative reports—for example, Sima Qian stated that Betelgeuse’s color was between the redness of Antares and the blueness of Bellatrix, another star in Orion—allowed the team to approximate Betelgeuse’s color at specific points in time.

“The very fact that it changed in color within two millennia from yellow-orange to red tells us, together with theoretical calculations, that it has 14 times the mass of our Sun – and the mass is the main parameter defining the evolution of stars,” Neuhäuser said.

Betelgeuse is going through some remarkable changes at present. A few years ago, the giant, brilliant star began dimming. At its peak, the star was 40% fainter than normal. Now, astrophysicists believe Betelgeuse had the star’s equivalent of an odious burp, one that created a cloud that partially obscured the star from our view.

Betelgeuse is near the end of its life, and no one knows exactly when it will explode in a dazzling supernova. We’re surely in for more technicolor surprises from this familiar giant star.

More: The Mystery of Betelgeuse’s Weird Dimming Is Likely Solved

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Strange Radio Signal From Galactic Center Has Astronomers Flummoxed

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Over the course of 2020, astronomers in Australia detected a mysterious batch of radio waves coming from somewhere near the center of the galaxy. But when the team trained a more sensitive instrument toward the source, they saw it only once more before it disappeared, behaving differently than it had before. The signal is described in a paper published today in the Astrophysical Journal.

“The strangest property of this new signal is that it has a very high polarisation. This means its light oscillates in only one direction, but that direction rotates with time,” said Ziteng Wang, an astrophysicist at the University of Sydney and the lead author of the new study, in a university press release. In other words, the radio waves were intermittently corkscrewing to Earth, without any rhyme or reason. And since they were detected, the trail’s gone cold.

The signal was discovered using the Australian Square Kilometre Array Pathfinder Variables and Slow Transients (ASKAP VAST) Survey, a radio telescope based in extremely remote Western Australia. The mystery object that produced the signal was named ​​ASKAP J173608.2-321635, for the telescope that found it and its coordinates in the sky.

“This object was unique in that it started out invisible, became bright, faded away and then reappeared. This behaviour was extraordinary,” said Tara Murphy, also an astrophysicist at the University of Sydney and a co-author of the paper, in the same release.

When the radio source went dark, the team checked the visible light spectrum, finding nothing. They also turned to a different radio telescope, which yielded a similar amount of nothing. But then, using the MeerKAT radio telescope in South Africa, the team at last spotted the object again, but it disappeared within a day. The researchers haven’t seen it since.

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The Milky Way as seen from Uruguay. The radio source came from near the galactic center.
Photo: MARIANA SUAREZ/AFP (Getty Images)

“As for why a source would stop emitting, it could be something related to instabilities in the magnetic field. Magnetic fields can get tangled up and then release energy in bursts,” said David Kaplan, a co-author of the paper and an astrophysicist at the University of Wisconsin-Milwaukee, in an email to Gizmodo. “This happens with our Sun, with magnetars, and with other sorts of objects. So it’s not so much that it stopped emitting, as it only emits sporadically (most of the time it’s off).”

The researchers have a few ideas for what the radio source could’ve been, but they aren’t sure about any of them. The radio wave pattern bears similarities to a class of objects called Galactic Centre Radio Transients, though it also has some differences. Galactic Centre Radio Transients are not one specific object but rather a group of radio-emitting objects around the Milky Way’s center that don’t have a certain identity.

Because of the characteristics of its burst, the team thought at first that ASKAP J173608.2-321635 might be a pulsar—a spinning dead star whose brightness regularly varies to observers on Earth. But this object’s brightness fluctuations weren’t regular, and its lack of other electromagnetic waves meant it didn’t resemble a small brown dwarf star or a highly magnetic magnetar. It may have been an “oddball” pulsar, Kaplan said, but the team won’t know for sure with their current data.

Even if ASKAP J173608.2-321635 isn’t seen again, they hope that future observations will determine if the object was the rule or the exception—that is, whether the source is the first of a hitherto-unobserved class of objects or something else.

Instead of leapfrogging from radio telescope to radio telescope in the future, the team hopes to use the Square Kilometre Array, the world’s largest radio telescope with 130,000 antennas, for its future observations of distant radio sources. The array is expected to start routine science observations toward the end of this decade.

More: New South African Telescope Releases Epic Image of the Galactic Center

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This Blasted Star Is Getting the Hell Out of the Milky Way

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Careening through the Milky Way at nearly 2 million miles per hour, the star LP 40–365 shows no signs of stopping. A team of astronomers recently figured out that the star was propelled into its current speedrun by a supernova explosion millions of years ago.

LP 40–365 is unusual. It’s a white dwarf, a small, compact star at the end of its life, and it’s very rich in metals. LP 40–365 also has own atmosphere, which is mostly composed of oxygen and neon. But most important to this story is that the star is a runaway from a huge stellar explosion, which set in motion its dash out of the galaxy.

When a white dwarf is orbiting another (in what’s called a white dwarf binary), one star gives up mass to the other, which gobbles it up steadily. The binaries can also emit gravitational waves—perturbations in spacetime—as they orbit one another, with the hungry star (the accretor) in the duo detonating in a huge thermonuclear explosion.

The team behind the new research isn’t sure whether stars like LP 40–365 are typically the donors or the accretors in their white dwarf binary systems, but they believe this particular hot metal ball is basically stellar shrapnel from the accreting star, which eventually exploded in fantastic fashion. Their findings were published this week in The Astrophysical Journal Letters.

“To have gone through partial detonation and still survive is very cool and unique, and it’s only in the last few years that we’ve started to think this kind of star could exist,” Odelia Putterman, a researcher now at Occidental College and a co-author of the paper, told The Brink, a publication of Boston University.

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The team found the star using observations from the Transiting Exoplanet Survey Satellite (TESS) and the Hubble Space Telescope, which turned up a fast-moving object with a regular pattern of dimming and brightening. That suggested the star was slowly rotating—completing its rotation every nine hours—as it hurtled through space. That’s a pretty slow rotation rate, and weird to think about in conjunction with how fast the star is moving through space. It’s from that rotation rate that the team figures the white dwarf is the remnant of one star in a binary system collapsing in on itself, blasting its partner and all else in the area outwards at extraordinary speed. Based on the team’s calculations, they believe LP 40–365 has been traveling from its origin galaxy for a little over 5 million years.

“The star is basically being slingshotted from the explosion, and we’re [observing] its rotation on its way out,” Putterman told The Brink .

More: Astronomers Think They’ve Spotted a Rare Kind of Supernova Only Predicted to Exist

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Neutron Stars Have Mountains That Are Less Than a Millimeter Tall

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An artist’s depiction of a neutron star.
Image: ESO / L. Calçada

A team of astrophysicists recently used new models of neutron stars to map the mountains—tiny raised areas—on the stars’ otherwise perfectly spherical structures. They found that the greatest deviations were still extraordinarily small due to the intense gravitational pull, clocking in at less than a millimeter tall.

Neutron stars are the dead cores of once-huge stars that collapsed in on themselves. They are the densest objects in the Universe aside from black holes. They’re called neutron stars because their gravity is so intense that the electrons in their atoms collapse into the protons, forming neutrons. They’re so compact that they pack a mass greater than that of our Sun into a sphere no wider than a city.

The team’s assessment of the “mountains” on these neutron stars comes in two papers currently hosted on the pre-print server arXiv; together, the papers assess how big these mountains can be. The team’s results are being presented today at Royal Astronomical Society’s National Astronomy Meeting.

“For the past two decades, there has been much interest in understanding how large these mountains can be before the crust of the neutron star breaks, and the mountain can no longer be supported,” said Fabian Gittins, an astrophysicist at the University of Southampton and lead author of the two papers, in a Royal Astronomical Society press release.

Previous work indicated that neutron star mountains could be a few centimeters tall—many times larger than what the recent team has estimated. The earlier calculations assumed that the neutron star would sustain such large bumps on its surface if it were strained to its limits, like Atlas holding up the world. But the recent modeling found that the earlier calculations are unrealistic behavior to expect from a neutron star.

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“For the past two decades, there has been much interest in understanding how large these mountains can be before the crust of the neutron star breaks, and the mountain can no longer be supported,” Gittins explains in the release.

Past work has suggested that neutron stars can sustain deviations from a perfect sphere of up to a few parts in 1 million, implying the mountains could be as large as a few centimeters. These calculations assumed the neutron star was strained in such a way that the crust was close to breaking at every point. However, the new models indicate that such conditions are unlikely.

“A neutron star has a fluid core, and elastic crust and on top of that a thin fluid ocean. Each region is complicated, but let’s forget about the fine print,” Nils Andersson, a co-author on both papers and an astrophysicist at the University of Southampton, said in an email. “What we have done is build models that join these different regions together in the correct way. This allows us to say when and where the elastic crust first breaks. Previous models have assumed that the strain is maximal at all points at the same time and this leads to (we think) estimated mountains that are a bit too large.”

These crustal yields would mean that the energy from the mountain would be released into a larger area of the star, Andersson said. While based on computer models, the crust shifts would “not be dramatic enough to make the star collapse, though, because the crust region involves fairly low density matter,” Andersson said.

Intriguing questions remain. There’s a possibility, Andersson said, that after a first crustal break, larger mountains than those the team modeled could occur due to the flow of matter across the star’s surface. But even those mountains would be much smaller than a molehill, compressed by the immense gravity of the stars.

More: Astrophysicists Detect Black Holes and Neutron Stars Merging, This Time for Certain

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An Ancient Hypernova Filled This Star With Unusual Elements

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The star SMSS J200322.54-114203.3 at center, imaged as part of the SkyMapper survey.
Image: Da Costa/SkyMapper

The peculiar elemental makeup of one star in the Milky Way could be due to a massive type of stellar collapse in the early universe, a team of astronomers announced today. The finding could help astronomers understand the diversity of ways in which the universe’s heavy elements, like gold, originated.

The star in question, SMSS J200322.54-114203.3, is 7,500 light-years from the Sun and sits in the halo on the periphery of our galaxy. The team believes a stellar explosion even more energetic than a supernova—called a “hypernova”—is responsible for the star’s unusual chemistry. Elements heavier than iron require intense forces to be created: The merging of neutron stars, as well as the collapse of large stars in supernova explosions, are two common ways. Heavy elements are forged when lighter elements absorb many neutrons, some of which decay into protons, eventually landing on a stable isotope of a heavy element. Those elements are then dispersed into the interstellar medium by the force of the explosion or collision, eventually ending up in other stars and on planets like Earth.

Scientists say this particular star’s chemistry—a very low iron content and very high amounts of nitrogen, zinc, europium, and thorium—pointed to a different source of heavy elements than the typical neutron star merger. Their research is published today in Nature.

“The key question this research addresses is, ‘How were the heaviest elements produced in the early universe?’” said David Yong, an astronomer at the Australian National University and lead author of the recent paper, in an email. “The mergers of neutron stars (the extremely dense remnants of massive stars) were recently confirmed as sources … Our results reveal magnetorotational hypernova (an energetic explosion of a rapidly rotating star with magnetic fields) as another source of those heavy elements.”

The team was looking for a star with a large amount of heavy elements like zinc, thorium, and europium. They sifted through 26,000 stars from the SkyMapper Southern Sky Survey, a project that has built up a catalogue of some 600 million objects in the night sky. They narrowed down to a set of 150 candidates, but only SMSS J200322.54-114203.3 had the specific high-nitrogen, high-zinc signature the team was searching for. The star simply had more heavy elements than it should, based on known rates and energies of star deaths.

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“The extra amounts of these elements had to come from somewhere,” said Chiaki Kobayashi, an astronomer from the University of Hertfordshire in the United Kingdom, in an ARC Center press release. The team determined that the star formed some 13 billion years ago, quite early in the universe’s timeline, out of the soupy aftermath of a gargantuan hypernova. Hypernovae are really a type of supernova; they describe stellar explosions about 10 times more energetic than an ordinary supernova.

“Since the star has such low iron content, it must have formed when the Milky Way galaxy was very young,” Yong said. “Given the short time constraint, it is easier to produce all elements in a single event (magnetorotational hypernova) rather than in the neutron star merger scenario.”

The team believes this huge, magnetized, fast-spinning star collapsed 13 billion years ago, blasting elements hither and thither. Kobayashi’s models of the Milky Way’s chemical evolution suggest that hypernovae may have had a bigger part to play in shaping the galactic chemistry we see today.

Finding more stars with a similar makeup will likely help the team understand just how important hypernovae were in the early cosmic kitchen. For now, SMSS J200322.54-114203.3 is the sole indicator of the elemental mystery at large.

More: Astronomers Think They’ve Spotted a Rare Kind of Supernova Only Predicted to Exist

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Astronomers Found a White Dwarf Star the Size of Our Moon

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An artist’s depiction of the white dwarf, left, in comparison with our Moon, right.
Illustration: Giuseppe Parisi

Imagine a white-hot, dying star that contains more mass than our Sun packed into an orb just a little larger than our Moon. That’s ZTF J190132.9+145808.7, a record-setting white dwarf recently identified by astronomers.

The star was seen from the Zwicky Transient Facility, which operates out of California and Hawaii, hence the first letters in the object’s unwieldy name. Based on the object’s extreme magnetic field and mass—nearly a billion times as strong as the Sun and 1.35 times its mass—the researchers believe it is the result of a white dwarf merger. Their results were published this week in Nature.

White dwarfs (also called degenerate dwarfs) are the end stage of many small and medium-sized stars. When white dwarfs orbiting each other (in what’s called a binary star system) eventually merge, they can explode in a supernova. But if they aren’t that massive, they just form one bigger white dwarf. “We caught this very interesting object that wasn’t quite massive enough to explode,” said Ilaria Caiazzo, an astrophysicist at the California Institute of Technology and lead author of the paper, in a Keck Observatory press release. “We are truly probing how massive a white dwarf can be.”

ZTF J190132.9+145808.7 also has a very fast rotation, performing a full revolution in just under seven minutes. Its diameter is about 2,670 miles, slightly more petite the previously known smallest white dwarfs, which both had diameters of about 3,100 miles. Studying the strength of the star’s magnetic field in conjunction with its fast rotation led the research team to the conclusion that the dwarf was once two separate stars that came together in a dense, fast-spinning collab.

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The team believes that ZTF J190132.9+145808.7 has a chance of turning into a neutron star, one possible end-stage of stellar life in which a star will end up collapsing in on itself. “It is so massive and dense that, in its core, electrons are being captured by protons in nuclei to form neutrons,” Caiazzo said in the same release. “Because the pressure from electrons pushes against the force of gravity, keeping the star intact, the core collapses when a large enough number of electrons are removed.”

Plenty of known unknowns abound, such as how strong magnetic fields arise from white dwarf mergers and the prevalence of such mergers among white dwarfs in space. The telescopes keep looking skywards, so as long as the dwarfs remain large enough to be seen, it’s safe to say there will be more record-breakers in the future.

More: Astronomers Discover First Known Planet to Orbit a White Dwarf Star

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