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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...

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...

When the Swift Gamma Burst Mission spacecraft first detected the flash within the constellation Draco, astronomers thought it was a gamma-ray burst from a collapsing star. On March 31, however, UC Berkeley's Joshua Bloom sent out an email circular suggesting that it wasn't a typical gamma-ray burst at all, but a high-energy jet produced as a star about the size of our sun was shredded by a black hole a million times more massive. Careful analysis of the Swift data and subsequent observations by the Hubble Space Telescope and the Chandra X-ray Observatory confirmed Bloom's initial insight. The details are...

Scientists have seen the afterglow of a gamma-ray burst just nine minutes after the explosion, a result of precision coordination and fast slewing of ground-based telescopes upon detection of the burst by NASA's High-Energy Transient Explorer (HETE) satellite. The quick turnaround has so far allowed scientists to determine a minimum distance to the explosion, which likely marks the creation of a black hole. Results continue to pour in, as nearly 100 telescopes in 11 countries have tracked the burst. The burst was detected on Friday, Oct. 4, at 8:06 a.m. EDT. NASA's Hubble Space Telescope and Chandra X-ray Observatory observed...

1.) How did the Universe begin? What “type” of inflation occurred? What preceded and/or caused inflation? 2.) What explains neutrino mass? Are neutrinos Dirac or Majorana particles? Are there heavy, sterile neutrino species? 3.) Why is our Universe matter-dominated? More matter than antimatter permeates the Universe. 4.) What is dark matter? Its effects are understood, not its underlying cause. 5.) What is dark energy? Its properties indicate a constant, positive spatial energy density.

The supermassive blackhole at the center of SgrA*. (EHT Collaboration) =================================================================== Four and a half billion years ago, our pale blue dot was born in the rubble left over from the birth of a star. Since then, we've been locked in a cosmic dance; Earth whirls around the Sun; and the Sun whirls around the galactic center, the dark, mysterious heart of the Milky Way. Contained in that dark heart, around which the entire galaxy revolves, is a supermassive black hole named Sagittarius A*, clocking in at around 4.3 million times the mass of the Sun. We've been able to...

Supermassive Black Hole Spewing Out Jets An artist’s conception of a supermassive black hole at the center of a galaxy. Credit: Image courtesy of ESA/AOES Medialab ************************************************************************************** Update: Meet Sagittarius A* – Astronomers Reveal First Image of the Black Hole at the Heart of the Milky Way Today (May 12, 2022) at 9:00 a.m. EDT (6:00 a.m. PDT, 15:00 CEST) The European Southern Observatory (ESO) and the Event Horizon Telescope (EHT) project will hold a press conference to present new Milky Way results from the EHT. The ESO Director General will deliver the opening words. EHT Project Director Huib Jan...

Is the universe we see – stars, moons, planets, clusters of galaxies – a small, accidental tip of an infinite cosmic iceberg? During the epoch of inflation, thought to have been triggered by the phase transition that marked the end of the grand unification at approximately 10^−36 seconds after the Big Bang, the accelerating expansion of space was far more dramatic than in today’s universe. Inflation lasted for only 10^-32 seconds, but the universe expanded at an absolutely staggering rate, increasing in size by a factor of 10^26. During this period, no objects – even two elementary particles – remained...