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Gravitational waves from massive black holes challenge current astrophysical models The LIGO-Virgo-KAGRA (LVK) Collaboration has detected the merger of the most massive black holes ever observed with gravitational waves using the US National Science Foundation (NSF)-funded LIGO observatories. The powerful merger produced a final black hole approximately 225 times the mass of our Sun. The signal, designated GW231123, was detected during the fourth observing run of the LVK network on November 23, 2023. LIGO, the Laser Interferometer Gravitational-wave Observatory, made history in 2015 when it made the first-ever direct detection of gravitational waves, ripples in space-time. In that case, the...

This artist's conception depicts ordinary matter in the warm, thin gas making up the intergalactic medium (IGM)—which has been difficult for scientists to directly observe until now. Different colors of light travel at different speeds through space. Here, the artist has used blue to highlight denser regions of the cosmic web, transitioning to redder light for void areas. Credit: Jack Madden, IllustrisTNG, Ralf Konietzka, Liam Connor/CfA ==================================================================================== Using Caltech's DSA-110 radio telescope, astronomers pinpoint whereabouts of "fog" between galaxies ============================================================== The vast majority of matter in the universe is dark—it is entirely invisible and detected only through its gravitational effects....

Scientists predict up to 100 invisible galaxies may orbit the Milky Way, hiding just beyond our current detection limits. Credit: Shutterstock *********************************************************************** Astronomers may be on the verge of uncovering a long-lost galactic population. Using ultra-high-resolution simulations and sophisticated modeling, researchers at Durham University predict that the Milky Way could be surrounded by up to 100 previously undetected satellite galaxies. These faint, elusive “orphan galaxies” may have been stripped of their dark matter halos, making them nearly invisible to current telescopes. But with the advent of powerful new instruments like the Rubin Observatory, scientists believe we’re finally approaching the ability...

That’s the conclusion reached by one researcher from the University of North Carolina: black holes can’t exist in our Universe — not mathematically, anyway. “I’m still not over the shock,” said Laura Mersini-Houghton, associate physics professor at UNC-Chapel Hill. “We’ve been studying this problem for a more than 50 years and this solution gives us a lot to think about.” In a news article spotlighted by UNC the scenario suggested by Mersini-Houghton is briefly explained. Basically, when a massive star reaches the end of its life and collapses under its own gravity after blasting its outer layers into space —...

You can manipulate a black hole as much as you like but you’ll never get rid of its event horizon, a new study suggests. This may sound a little odd, the event horizon is what makes the black hole, well… black. However, in the centre of a black hole, hidden deep inside the event horizon, is a singularity. A singularity is a mathematical consequence, it is also a point in space where the laws of physics do not apply. Mathematics also predicts that singularities can exist without an associated event horizon, but this means that we’d be able to physically...

WASHINGTON (Reuters) - A supermassive black hole appears to be homeless in the cosmos without a galaxy to nestle in, Hubble Space Telescope scientists reported on Wednesday. Most monster black holes lurk at the heart of massive galaxies, slurping up matter from the galactic center with a pull so strong that nothing, not even light, can escape. But a team of European astronomers reported in the journal Nature that a particular black hole some 5 billion light-years away has no evidence of a host galaxy. A light-year is about 6 trillion miles, the distance light travels in a year. The...

A simulation of the ‘cosmic web’, the vast network of threads and filaments that extends throughout the Universe. Stars, galaxies, and galaxy clusters spring to life in the densest knots of this web, and remain connected by vast threads that stretch out for many millions of light-years. These threads are invisible to the eye, but can be uncovered by telescopes such as ESA’s XMM-Newton. Credit: Illustris Collaboration / Illustris Simulation ======================================================================== A vast filament of gas stretching across the cosmos may help solve the mystery of the Universe’s missing matter. Astronomers have identified a massive filament of hot gas connecting...

Here’s what you’ll learn when you read this story: A new hypothesis from physicists at the University of Portsmouth in the U.K. challenges the long-standing Big Bang Theory as the ultimate origin of the universe. This new “Black Hole Universe” hypothesis, suggests that our universe possibly “bounced” from the formation of larger black hole in another parent universe. While intriguing, the Big Bang Theory is the undisputed cosmological champ for a reason, so it'll take lots of rigorous experiments to confirm its theoretical conclusions. Throughout human history, there has been no greater question than “where do we come from?” This...

If it’s out there, could we observe it soon?Here’s what you’ll learn when you read this story: Some physicists believe that a fifth fundamental force could be the cause of some observational anomalies. A study is investigating ways to closely examine the trajectories of well-documented asteroids to hopefully detect anomalies that could provide evidence of such a force. Although the study shows no fifth force anomaly present in the asteroid Bennu, future explorations of the asteroid Apophis could provide an even better chance to find this elusive force—if it exists at all. According to the current Standard Model, four fundamental...

For centuries, most scientists have shared the belief that light behaves as both a wave and a particle. This idea, then, became the central component to quantum theory, sprouting the field of science known as quantum mechanics. The double-slit experiment supported the idea, showing bright and dark bands that indicated wave-like interference. But now, a new study suggests that this experiment might not lock us into seeing light as a wave. According to the experts, we can interpret those interference bands using quantum particles alone. The research was led by Gerhard Rempe, the director of the Max Planck Institute for...

CREDIT: NASA, ESA, STScI, Yuhan Yao (UC Berkeley); Image Processing: Joseph DePasquale (STScI) ************************************************************** A traveling black hole stalking the cosmos for stellar prey recently revealed itself to NASA telescopes in a tidal disruption event (TDE), shredding and swallowing a star in a radioactive burst. With its brilliant flash, the TDE AT2024tvd lit up several observatories, including NASA’s Hubble Space Telescope, Chandra X-Ray Observatory, and the NRAO Very Large Array. The TDE event took place 600 million light-years from Earth, allowing astronomers a new glimpse at black hole physics to be published in a future issue of The Astrophysical Journal...

In a landmark discovery, astronomers have confirmed the existence of a solitary stellar-mass black hole—an object with immense gravity, yet no visible companion, quietly roaming the depths of the Milky Way galaxy. Identified in the direction of the Sagittarius constellation, this black hole is believed to be around seven times more massive than our Sun and marks the first confirmed detection of a black hole not bound to another star. The study, published in The Astrophysical Journal and led by Kailash C. Sahu and colleagues at the Space Telescope Science Institute, relied on more than a decade of high-precision data...

This artist’s impression illustrates the mechanism that could be at the origin of the powerful bursts of X-ray light seen from a newly awakened black hole named Ansky. Credit: ESA A mysterious black hole in a distant galaxy just woke up after decades of silence—and it’s putting on a cosmic light show! **************************************************************************** ESA’s XMM-Newton and other X-ray telescopes are capturing massive bursts of energy known as quasiperiodic eruptions (QPEs) that defy current theories. Unlike anything seen before, these powerful flashes may be rewriting the rulebook on how black holes behave, evolve, and interact with their surroundings. XMM-Newton Observes Rare...

Astronomers using the NASA/ESA Hubble Space Telescope have captured an amazing new photo of the spiral galaxy NGC 4941. This Hubble image shows NGC 4941, a spiral galaxy some 67 million light-years away in the constellation of Virgo. The color image is composed of near-infrared, optical and ultraviolet observations from Hubble’s Wide Field Camera 3 (WFC3). Six filters were used to sample various wavelengths. The color results from assigning different hues to each monochromatic image associated with an individual filter. Image credit: NASA / ESA / Hubble / D. Thilker. ================================================================== NGC 4941 is located approximately 67 million light-years away...

Dark energy, a mysterious force that scientists believe is behind the accelerated expansion of the universe, is weakening — which could result in the universe over the course of billions of years collapsing on itself, according to new research. An international group of more than 900 researchers studying the expansion of the universe presented their findings on Wednesday during the American Physical Society's Global Physics Summit in Anaheim, Calif. The scientists, who are collaborating on something called the Dark Energy Spectroscopic Instrument (DESI) are studying the history of the universe's expansion out to 11 billion years in the past. They...

Galaxies observed by the JWST with those rotating one way circled in red, those rotating the other wat circled in blue (Image credit: Monthly Notices of the Royal Astronomical Society (2025)) ==================================================================================== Without a doubt, since its launch, the James Webb Space Telescope (JWST) has revolutionized our view of the early universe, but its new findings could put astronomers in a spin. In fact, it could tell us something profound about the birth of the universe by possibly hinting that everything we see around us is sealed within a black hole. The $10 billion telescope, which began observing the cosmos...

A radical new theory suggests that black holes could transition into white holes, creating a location in space where time begins by ejecting material back into the cosmos. The theory also suggests a quantum mechanics link between black and white holes, including an aspect of enigmatic dark matter. The research team behind the new theory believes their work could represent a critical step toward reconciling quantum mechanics and gravity, potentially leading to new theories about the universe’s very nature. Black Holes (and White Holes) Have Long Fascinated Scientists First proposed by Albert Einstein, black holes have long fascinated scientists. Still,...

A supersolid is a paradox of physics — a material that is both solid and liquid at the same time. This contradictory form of matter was first proposed more than 60 years ago, and, for a long time, people thought it was too nuts to actually exist. But we’re talking about the realm of quantum mechanics, and normal expectations should be thrown out the window. In 2007, researchers at ETH Zurich and MIT unveiled the world’s first supersolids, starting with superflooding sodium and rubidium, respectively. Now, an international team of researchers has unveiled an entirely new route to supersolidity, harnessing...

Artist’s impression of the bright, very early active galactic nucleus that was found by Bañados and his colleagues, which has fundamental implications for black hole growth in the earliest billion or so years of cosmic history. Credit: NSF/AUI/NSF NRAO/B. Saxton ======================================================================================= Astronomers have spotted a young, blazing black hole that was already growing at a furious pace just one billion years after the Big Bang. This rare discovery provides a key to understanding how supermassive black holes formed in the universe’s earliest days. Astronomers have identified a crucial clue in understanding how supermassive black holes grew so quickly in the...

Does the light scatter that black holes produce mean there are actually fewer objects than we are seeing in the night skies? Thank you.