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You never really know what you might find hiding in your own backyard, especially if those things are particularly adept at escaping detection. Just 1,924 light-years from the Solar System, in the constellation of Aquila, astronomers have just discovered a black hole. And it's not just any black hole. Named Gaia BH3, or BH3, the object is the most massive stellar-mass black hole we've ever spotted in the Milky Way, clocking in at a hefty 33 times the mass of the Sun. It's the second-closest black hole we've found to our home-world, and it's just hanging out, quietly in space,...

Explanation: What's happening to the big black hole in the center of our galaxy? It is sucking in matter from a swirling disk -- a disk that is magnetized, it has now been confirmed. Specifically, the black hole's accretion disk has recently been seen to emit polarized light, radiation frequently associated with a magnetized source. Pictured here is a close-up of Sgr A*, our Galaxy's central black hole, taken by radio telescopes around the world participating in the Event Horizon Telescope (EHT) Collaboration. Superposed are illustrative curved lines indicating polarized light likely emitted from swirling magnetized gas that will soon...

There are striking analogies between the interpersonal relationships of humans and the gravitational interaction of physical bodies in space. Consider a two-body system. In both realms, the systems can have stable configurations, leading to long-lived marriages or stellar binaries. But when a third body interacts strongly with these systems, a non-hierarchical three-body system often displays chaos with one of the members ejected and the other two remaining bound. This brings up analogies with interpersonal relationships when a third body is added to a non-hierarchical two-body system. The chaotic gravitational dynamics in a system of three stars inspired the storyline for...

The fabric of the cosmos, as we currently understand it, comprises three primary components: 'normal matter,' 'dark energy,' and 'dark matter.' However, new research is turning this established model on its head. A recent study conducted by the University of Ottawa presents compelling evidence that challenges the traditional model of the universe, suggesting that there may not be a place for dark matter within it. Dark matter, a term used in cosmology, refers to the elusive substance that does not interact with light or electromagnetic fields and is only identifiable through its gravitational effects. Despite its mysterious nature, dark matter...

I got a lot of questions last week about an article in Quanta Magazine about Dark Dimensions. it's about an idea motivated by string theory that combines large extra dimensions with dark matter. I had a look at the paper.The paper is here: https://arxiv.org/abs/2311.05318The article in quanta magazine is here: https://www.quantamagazine.org/...String theory nonsense makes comeback | 8:12Sabine Hossenfelder | 1.13M subscribers | 147,734 views | February 7, 2024

The James Webb Space Telescope peered 13.4 billion years into the past and found a black hole-sized conundrum. The oldest supermassive black hole astronomers have ever seen is gorging messily on the heart of its host galaxy, which may ultimately doom the black hole along with its prey. In the process, this ancient black hole — or at least as it looked 13.4 billion years ago — may offer important clues about how the universe’s first supermassive black holes formed and grew. University of Cambridge astrophysicist Roberto Maiolino and his colleagues recently used the James Webb Space Telescope (JWST) instruments...

Today, supermassive black holes and their host galaxies tell a specific story in terms of mass. But JWST reveals a different story early on. primordial black holes The overdense regions that the Universe was born with grow and grow over time, but are limited in their growth by both the initial small sizes of the overdensities and also by the presence of radiation that's still energetic, which prevents structure from growing any faster. It takes tens-to-hundreds of millions of years to form the first stars; clumps of matter exist long before that, however, and some may directly collapse to form...

"Stars could be there, we just can't see them." Hydrogen gas in the primordial galaxy J0613+52 with red indicating regions turning away from Earth and blue showing regions turning toward us (Image credit: STScI POSS-II with additional illustration by NSF/GBO/P.Vosteen.) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Astronomers have accidentally discovered a dark galaxy filled with primordial gas untouched that appears to have no visible stars. The researchers behind the discovery say this galaxy, designated J0613+52, could be "the faintest galaxy found to date." Interestingly, scientists using the Green Bank Telescope (GBT) discovered the "dark" galaxy through a complete error. "The GBT was accidentally pointed to...

India's space agency has successfully launched a rocket that is carrying an observatory which will study astronomical objects like black holes. It was launched from Sriharikota spaceport at 09:10 local time (03:40GMT) on Monday. This is only the second mission in the world of this nature after Nasa launched one in 2021. The space agency said it wanted to help scientists improve their "knowledge of black holes". "We will have an exciting time ahead," Indian Space Research Organisation (Isro) chairperson S Somanath said after the launch.

Illustration of how a failed supernova can become a black hole. (P. Jeffries/STScI/NASA/ESA) In 2009 a giant star 25 times more massive than the Sun simply…vanished. Okay, it wasn't quite that simple. It underwent a period of brightening, increasing in luminosity to a million Suns, just as if it was ready to explode into a supernova. But then it faded rather than exploding. And when astronomers tried to see the star, using the Large Binocular Telescope (LBT), Hubble, and the Spitzer space telescope, they couldn't see anything. The star, known as N6946-BH1, is now considered a failed supernova. The BH1...

Five Theories About the Universe to Blow Your Mind | 15:02Sideprojects | 733K subscribers | 1,568,801 views | November 8, 2022

Concept Black Hole Illustration A team of researchers has affirmed Stephen Hawking’s prediction about the evaporation of black holes via Hawking radiation, though they’ve provided a crucial modification. According to their research, the event horizon (the boundary beyond which nothing can escape a black hole’s gravitational pull) is not as important as previously believed in producing Hawking radiation. Instead, gravity and the curvature of spacetime play significant roles in this process. This insight extends the scope of Hawking radiation to all large objects in the universe, implying that, over a sufficiently long period, everything in the universe could evaporate. Research...

Einstein's general theory of relativity predicts the existence of black holes, formed when giant stars collapse. But that same theory predicts that their centers are singularities, which are points of infinite density. Since we know that infinite densities cannot actually happen in the universe, we take this as a sign that Einstein's theory is incomplete. But after nearly a century of searching for extensions, we have not yet confirmed a better theory of gravity.But we do have candidates, including string theory. In string theory all the particles of the universe are actually microscopic vibrating loops of string. In order to...

Artist impression of a black hole accretion. Astronomers led by the University of Southampton have discovered the largest cosmic explosion ever observed, known as AT2021lwx. Over ten times brighter than any known supernova and three times brighter than the brightest tidal disruption event, the explosion has been ongoing for more than three years. Researchers believe the explosion is due to a massive gas cloud, possibly thousands of times larger than the sun, being violently disrupted by a supermassive black hole. Credit John A. Paice www.johnapaice.com Astronomers have discovered the largest cosmic explosion ever observed, AT2021lwx, which is believed to have...

ESA / Hubble & NASA Physicists believe most of the matter in the universe is made up of an invisible substance that we only know about by its indirect effects on the stars and galaxies we can see. We’re not crazy! Without this “dark matter”, the universe as we see it would make no sense. But the nature of dark matter is a longstanding puzzle. However, a new study by Alfred Amruth at the University of Hong Kong and colleagues, published in Nature Astronomy, uses the gravitational bending of light to bring us a step closer to understanding. Invisible but...

Researchers at NOIRLab have released a version of the first image ever captured of a black hole that has been sharpened by using artificial intelligence. Photo courtesy of NOIRLab/Press Release April 13 (UPI) -- Researchers at the National Science Foundation's NOIRLab have applied AI technology to the first image ever captured of a black hole to present a clearer image of how gas spirals into supermassive black holes. When gas approaches a black hole, it swirls quickly and superheats because of friction, which in turn releases radiation that can be detected by radio telescopes. The team published a paper in...

Gaia Black Holes The location of the first two black holes discovered by ESA’s Gaia mission in the Milky Way. This map of our galaxy was also made by the Gaia mission. Gaia Black Hole 1 is located just 1560 light-years away from us in the direction of the constellation Ophiuchus and Gaia Black Hole 2 is 3800 light-years away in the constellation Centaurus. In galactic terms, these black holes reside in our cosmic backyard. Credit: ESA/Gaia/DPAC; CC BY-SA 3.0 IGO ESA’s Gaia mission has helped discover a new kind of black hole. The new family already has two members,...

In a distant galaxy, a supermassive black hole spewing radiation at near light speed has shifted its angle by a whopping 90 degrees to point directly toward Earth — a sharp turn that's puzzling physicists. Active galactic nuclei (AGN) are the hungry black holes at the cores of many other galaxies, and they accrete matter and spew powerful jets of high-energy particles known as relativistic jets. AGN are classified according to what part of the AGN is pointed toward Earth. The researchers also observed two lobes — areas where an AGN's jets interact with surrounding gas — where some jets...

Mirabilis, one of the pairs of dwarf galaxies detected. (NASA/CXC/University of Alabama/M. Micic et al./International Gemini Observatory/NOIRLab/NSF/AURA) For the first time, astronomers have spotted evidence of a pair of dwarf galaxies featuring giant black holes on a collision course with each other. In fact, they haven't just found just one pair – they've found two. The first pair of merging dwarf galaxies is in the cluster Abell 133, about 760 million light-years away from Earth, and the other is in the Abell 1758S galaxy cluster, which is about 3.2 billion light-years away. It's hoped that these sightings and further investigations...

Black and white map showing 25,000 black holes These aren't ordinary stars. (LOFAR/LOL Survey) The image above may look like a fairly normal picture of the night sky, but what you're looking at is a lot more special than just glittering stars. Each of those white dots is an active supermassive black hole. And each of those black holes is devouring material at the heart of a galaxy millions of light-years away – that's how they could be pinpointed at all. Released in 2021, this image contains 25,000 such dots, It's the most detailed map to date of black holes...