Latest news with #InstituteforAstronomy
Yahoo
a day ago
- Science
- Yahoo
Astronomers Just Discovered The Biggest Explosions Since The Big Bang
A never-before-seen type of giant space explosion – the biggest bangs since the Big Bang – has been accidentally captured by the Gaia space telescope. From the hearts of distant galaxies, the mapping telescope recorded sudden, extreme increases in brightness – colossal flares of light that lingered far longer than any such flares had been known to previously. These blasts were calculated to release as much energy as 100 Suns would over the course of their combined lifetimes. Analysis of that light revealed something that was both new and familiar at the same time: stars being torn apart by black holes, but on a scale we hadn't observed before. Each star was a large one, at least three times as massive as the Sun; and each black hole was a supermassive beast lurking in the center of the star's host galaxy. Such events are usually known as tidal disruption events, or TDEs. Astrophysicists are calling these new ones 'extreme nuclear transients' – ENTs for short. "We've observed stars getting ripped apart as tidal disruption events for over a decade, but these ENTs are different beasts, reaching brightnesses nearly 10 times more than what we typically see," says astrophysicist Jason Hinkle of the University of Hawaiʻi's Institute for Astronomy (IfA). "Not only are ENTs far brighter than normal tidal disruption events, but they remain luminous for years, far surpassing the energy output of even the brightest known supernova explosions." The rather tame term 'tidal disruption' is used to describe what gravitational forces do to an object that gets too close to a black hole. At a certain point, the power of the external gravitational field surpasses the gravity holding an object together, and it comes apart in a wild scream of light before at least partially falling into the great unknown beyond the black hole's event horizon. There are telescopes trained on the sky to catch these screams, applying a wide field of view to take in as much of the sky as possible, waiting for those unpredictable flares that denote the death throes of an unlucky star. Astronomers have managed to observe a good number of TDEs, and know roughly how they should play out. There's a sudden brightening in a distant galaxy, with a light curve that rises to a rapid peak before gradually fading over the course of weeks to months. Astronomers can then analyze that light to determine properties such as the relative masses of the objects involved. Gaia was a space telescope whose mission was to map the Milky Way in three dimensions. It spent a great deal of time staring at the sky to capture precise parallax measurements of the stars in the Milky Way. On occasion, however, it managed to exceed its mission parameters. When combing through Gaia data, Hinkle and his colleagues found two strange events: Gaia16aaw, a flare recorded in 2016; and Gaia18cdj, which the telescope caught in 2018. Both events bore a strong similarity to an event recorded by the Zwicky Transient Facility in 2020. Because that event was so insanely powerful, and because it was given the designation ZTF20abrbeie, astronomers nicknamed it "Scary Barbie". Hinkle and his team determined that Gaia16aaw and Gaia18cdj are the same kind of event as Scary Barbie, and set about trying to figure out what caused them. They ruled out supernova explosions – the events were at least twice as powerful as any other known transients, and supernovae have an upper brightness limit. A supernova, the team explained, typically releases as much light as the Sun will in its entire, 10-billion-year lifespan. The output of an ENT, however, is comparable to the lifetime output of 100 Suns all rolled together. Rather, the properties of the ENT events, the researchers found, were consistent with TDEs – just massively scaled up. That includes how much energy is expended, and the shape of the light curve as the event brightens and fades. ENTs are incredibly rare – the team calculated that they are around 10 million times less frequent than supernovae – but they represent a fascinating piece of the black hole puzzle. Supermassive black holes are millions to billions of times the mass of the Sun, and we don't have a clear idea of how they grow. ENTs represent one mechanism whereby these giant objects can pack on mass. "ENTs provide a valuable new tool for studying massive black holes in distant galaxies. Because they're so bright, we can see them across vast cosmic distances – and in astronomy, looking far away means looking back in time," says astrophysicist Benjamin Shappee of IfA. "By observing these prolonged flares, we gain insights into black hole growth during a key era known as cosmic noon, when the universe was half its current age [and] when galaxies were happening places – forming stars and feeding their supermassive black holes 10 times more vigorously than they do today." The research has been published in Science Advances. Titan's Atmosphere 'Wobbles Like a Gyroscope' – And No One Knows Why A 'Crazy Idea' About Pluto Was Just Confirmed in a Scientific First A Giant Mouth Has Opened on The Sun And Even It Looks Surprised
Yahoo
2 days ago
- Science
- Yahoo
Astronomers discover most powerful cosmic explosions since the Big Bang
When you buy through links on our articles, Future and its syndication partners may earn a commission. Astronomers have discovered the most powerful cosmic explosions since the Big Bang, naming them "extreme nuclear transients." These incredibly energetic explosions occur when stars with masses at least three times greater than that of the sun are torn apart by supermassive black holes. While such events have been witnessed before, astronomers say some of the ones recently discovered are powerful enough to be classified as a new phenomenon: extreme nuclear transients (ENTs). "We've observed stars getting ripped apart as tidal disruption events for over a decade, but these ENTs are different beasts, reaching brightnesses nearly ten times more than what we typically see," said Jason Hinkle, a researcher at the University of Hawaii's Institute for Astronomy (IfA) who led a study on these events, in a statement. "When I saw these smooth, long-lived flares from the centers of distant galaxies, I knew we were looking at something unusual." Hinkle discovered the existence of these ENTs while combing through data gathered on long-lasting flares originating from galactic centers. Two flares caught Hinkle's eye, recorded by the European Space Agency's Gaia spacecraft in 2016 and 2018, respectively. A third event discovered in 2020 by the Zwicky Transient Facility (ZTF) appeared similar to the two phenomena discovered by Gaia, which gave researchers clues that these belonged to a new class of extreme cosmic explosions. That's because these events appeared to release far more energy than other known star explosions, or supernovas, and seemed to last much longer. These explosions also differed from tidal disruption events (TDEs), which are massive releases of energy that occur when extreme gravitational forces around black holes rip stars apart, flinging much of their mass outward into space. But TDEs typically last only a matter of hours; the events studied by Hinkle and other researchers appeared to last much longer. "Not only are ENTs far brighter than normal tidal disruption events, but they remain luminous for years, far surpassing the energy output of even the brightest known supernova explosions," Hinkle said in the statement. One of these ENTs, which astronomers have named Gaia18cdj, released over 25 times more energy than the most powerful supernova ever discovered, more than the amount of energy that would be released by 100 suns throughout their entire lifetime. RELATED STORIES: — The most powerful explosions in the universe could reveal where gold comes from — 'Shocking' nova explosion of dead star was 100 times brighter than the sun — Astronomers discover black hole ripping a star apart inside a galactic collision. 'It is a peculiar event' Aside from being the most powerful known explosions in the universe, ENTs can help astronomers learn more about monster black holes in faraway galaxies. That's because the incredible brightness of these events means they can be seen across vast distances, according to IfA's Benjamin Shappee, who co-authored the study. "By observing these prolonged flares, we gain insights into black hole growth when the universe was half its current age and galaxies were busy places — forming stars and feeding their supermassive black holes 10 times more vigorously than they do today," Shappee said in the statement. A study on this discovery was published June 4 in the journal Science Advances.
Forbes
2 days ago
- Science
- Forbes
‘Biggest Booms Since The Big Bang' Found As Black Holes Shred Stars
Caption: Artist's concept of the formation of Extreme Nuclear Transients (ENTs). Astronomers have captured the most energetic explosions ever recorded in the universe since the big bang as massive stars get ripped apart by supermassive black holes. These Extreme Nuclear Transients, as they've been named, are a new class of rare and powerful cosmic explosions so bright they appear to release more energy than 100 supernovae (exploding stars). Black holes are such strong gravity that nothing can escape from them, not even photons of light. Supermassive black holes are the most massive type and reside at the centers of galaxies. While some of these black holes continuously consume gas and dust and glow for millions of years, others lie dormant — only revealing themselves when an unlucky star drifts too close. ENTs may be a glimpse into these otherwise unseen objects. 'We've observed stars getting ripped apart as tidal disruption events for over a decade, but these ENTs are different beasts, reaching brightnesses nearly ten times more than what we typically see,' said Jason Hinkle, a doctoral graduate of the University of Hawaii's Institute for Astronomy, who led the study published this week in Science Advances. These powerful events don't just flare and fade quickly. It can take over 100 days for an ENT to reach peak brightness and more than 150 days to dim to half its maximum. A tidal disruption event is when a star gets 'spaghettified' by a supermassive black hole, causing a brilliant flare, but an ENT is even more powerful. 'Not only are ENTs far brighter than normal tidal disruption events, but they remain luminous for years, far surpassing the energy output of even the brightest known supernova explosions," said Hinkle. These flares occur in the centers of galaxies and radiate more energy than any previously known event. At least 10 million times less frequent than supernovae, ENTs occur when massive stars — at least three times more massive than our sun — come too close to a supermassive black hole. A tidal disruption follows, tearing the stars apart and releasing more energy than 100 supernovae. What's different about them is their speed — ENTs allow astronomers to watch as a massive star is 'digested' over time by a supermassive black hole. 'These ENTs don't just mark the dramatic end of a massive star's life,' said Hinkle. 'They illuminate the processes responsible for growing the largest black holes in the universe.' Artist's concept of the formation of Extreme Nuclear Transients (ENTs). The research included data on the most energetic event yet recorded, an ENT named Gaia18cdj. A typical supernova emits about as much energy as the sun ever will over 10 billion years. Gaia18cdj emitted 25 times more energy than the most powerful supernova ever observed. The discovery came from scientists analyzing data from the European Space Agency's Gaia mission, which made three trillion observations of two billion stars while orbiting the sun between 2014 and 2025 when it ran out of fuel. It recorded unexplained flares in 2016 and 2018, with scientists discovering another — called ZTF20abrbeie and nicknamed 'Barbie' — in 2020, using data from the Zwicky Transient Facility survey telescope in California. Follow-ups were then made using data from other telescopes, including the Keck Observatory in Hawaii and NASA's Neil Gehrels Swift Observatory and WISE spacecraft. Artist's concept of the formation of Extreme Nuclear Transients (ENTs). Although all astronomy is looking back in time (even the sun's light is eight minutes old), the brightness of ENTs allows them to be seen over vast distances. That opens up the possibility of seeing them in a time called the 'cosmic noon,' when the universe was half its current age. This was "when galaxies were happening places — forming stars and feeding their supermassive black holes 10 times more vigorously than they do today,' said Benjamin Shappee, Associate Professor at IfA and co-author of the study. 'ENTs provide a valuable new tool for studying massive black holes in distant galaxies.' NASA's Nancy Grace Roman Space Telescope, launching as early as 2026, will use its infrared vision to catch these rare flashes from over 12 billion years ago — when the universe was just 10% of its current age — and help astronomers trace how black holes shaped galaxies over cosmic time. Wishing you clear skies and wide eyes.
Yahoo
19-04-2025
- Science
- Yahoo
Universe may revolve once every 500 billion years — and that could solve a problem that threatened to break cosmology
When you buy through links on our articles, Future and its syndication partners may earn a commission. In 1929, astronomer Edwin Hubble published a paper demonstrating that the universe is expanding. It gave rise to the Hubble constant, the number that describes how fast the universe is expanding. But it eventually created a puzzle, called the Hubble tension, because this cosmic expansion differs depending on what cosmic objects are used to measure it. A new mathematical model could resolve the Hubble tension by assuming the universe rotates. Related: After 2 years in space, the James Webb telescope has broken cosmology. Can it be fixed? The new research, published in March in the journal Monthly Notices of the Royal Astronomical Society, suggests that our universe completes one revolution every 500 billion years. This ultraslow rotation could resolve the discrepancy between different measurements of the Hubble constant. "The standard concordance cosmological model has some wrinkles," study co-author István Szapudi, an astronomer at the Institute for Astronomy at the University of Hawai'i at Mānoa, told Live Science in an email. "A slow rotation of the universe could solve the Hubble puzzle." Astronomers measure the universe's rate of expansion in a few ways. One involves looking at supernovas — the explosive deaths of giant stars — and measuring how quickly these supernovas recede. The other method utilizes the cosmic microwave background, the radiation present 380,000 years following the Big Bang. However, these two measurements differ by about 10%. The idea of a rotating universe isn't new; mathematician Kurt Gödel introduced the idea in a 1949 paper published in the journal Reviews of Modern Physics. Other researchers, like Stephen Hawking, have also explored this theory. In the new study, the team applied the rotation to the Hubble tension. Because all celestial objects — including planets, stars, galaxies and black holes — rotate, this behavior naturally extends to the universe as a whole, the study authors proposed. "Much to our surprise, we found that our model with rotation resolves the paradox without contradicting current astronomical measurements," Szapudi said. RELATED STORIES —Scientists may have finally found where the 'missing half' of the universe's matter is hiding —Rare quadruple supernova on our 'cosmic doorstep' will shine brighter than the moon when it blows up in 23 billion years —Scientists discover smallest galaxy ever seen: 'It's like having a perfectly functional human being that's the size of a grain of rice' The proposed glacial speed at which the universe may rotate is too slow to detect, but it would still affect the universe's expansion rate and does not require new physics. However, the model only incorporated some of the physics thought to be at play. "We use Newtonian physics with some input from General Relativity," Szapudi said. "A complete [General Relativity] treatment would be desirable." He also explained that their work assumes the universe is uniform and did not vary in density as it evolved. In future investigations, the team will contrast the rotating-universe model against other cosmological models.
Yahoo
17-04-2025
- Science
- Yahoo
The universe isn't just expanding—it may be spinning
The prevailing consensus in astrophysics is that the universe has spent the past 13-or-so billion years expanding outward in all directions, ever since the Big Bang. It's expanding at this very moment, and will continue to do so until… a number of possible theoretical endings. Meanwhile, the specific rate at which the universe is growing remains a longstanding point of contention known as the 'Hubble tension.' However, there may be a way to finally ease that tension—you just need to put a slight spin on everything. In simplest terms, the rate at which the universe expands on paper doesn't match actual astronomical observations. That speed—called the Hubble Constant—is measured in units of kilometers per second per megaparsec (km/s/Mpc), with a megaparsec measuring about 300,000 light years. The most widely accepted theoretical model, the Lambda/Cold Dark Matter model (ΛCDM), says the universe is growing at 67-68 km/s/Mpc. But what astronomers see through their equipment is a little faster, at about 73 km/s/Mpc. And therein lies the Hubble tension. In a study published in the April issue of the Monthly Notices of the Royal Astronomical Society, a team of researchers including experts at the University of Hawai'i's Institute for Astronomy argue that introducing a miniscule amount of rotation to standard mathematical model of the universe may provide the way to align both expansion theories.'Much to our surprise, we found that our model with rotation resolves the paradox without contradicting current astronomical measurements,' study co-author and astrophysicist? István Szapudi said in a statement. 'Even better, it is compatible with other models that assume rotation.' In addition to its mathematical compatibility, the concept also doesn't break any of the known laws of physics. The problem is detecting this spin, given just how slowly the universe may be turning. But while it is difficult to discern with current tools, the spin is still fast enough to influence the expansion of space over the eons. Szapudi and their colleagues' new model indicates the universe finishes a single rotation once every 500 billion years—meaning there's still quite a bit of time before the universe completes its first full circuit. 'To paraphrase the Greek philosopher Heraclitus of Ephesus, who famously said 'Panta Rhei' (everything moves), we thought that perhaps 'Panta Kykloutai,' everything turns,' said Szapudi. Looking ahead, astronomers hope to construct a full computer model of the universe based in part of their new theory. From there, they will hopefully be able to pinpoint signs of cosmic spinning to search for among the stars.
