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This is a new image of the Hubble Ultra Deep Field. By comparing Hubble Wide Field Camera 3 near-infrared exposures taken in 2009, 2012, and 2023, astronomers found evidence for flickering supermassive black holes in the hearts of early galaxies. One example is seen as a bright object in the inset. Some supermassive black holes do not swallow surrounding material constantly, but in fits and bursts, making their brightness flicker. Credit: NASA, ESA, Matthew Hayes (Stockholm University), Steven V.W. Beckwith (UC Berkeley), Garth Illingworth (UC Santa Cruz), Richard Ellis (UCL), Joseph DePasquale (STScI) =========================================================================== A Survey of Hubble’s Deepest Look...

Webb Telescope observations reveal that supermassive black holes starve galaxies of star-forming gas, as seen in ‘Pablo’s Galaxy’, where high-speed gas expulsion by the black hole has ceased new star formation. (Artist’s concept.) Credit: SciTechDaily.com ================================================================================= Using the James Webb Space Telescope, astronomers have uncovered that supermassive black holes can exhaust the resources necessary for star formation in their host galaxies, effectively starving them. This was observed in a galaxy similar in size to the Milky Way, located in the early universe. The discovery reveals that the black hole is actively preventing star formation by expelling essential star-forming gas at...

A recent study underscores the dynamic nature of black holes and extends similar thermodynamic characteristics to Extremely Compact Objects, advancing our comprehension of their behavior in quantum gravity scenarios.A paper titled "Universality of the thermodynamics of a quantum-mechanically radiating black hole departing from thermality," published in Physics Letters B highlights the importance of considering black holes as dynamical systems, where variations in their geometry during radiation emissions are critical to accurately describing their thermodynamic behavior.The study also suggests that extremely compact objects (ECOs) share these thermodynamic properties with black holes, regardless of their event horizon status. The significance of this...

An international team of astronomers has overturned a longstanding belief that stars and dark matter interact in a mysterious way to create uniform density structures across different galaxies. This finding, published in 'Monthly Notices of the Royal Astronomical Society (MNRAS)', challenges a theory that had perplexed scientists for 25 years. The research team, which includes scientists from Australia, the UK, Austria, and Germany, utilized the Very Large Telescope in Chile to observe and analyze 22 galaxies that are approximately four billion years old. The results revealed that the perceived uniformity in galaxy density may not be a real phenomenon but...

Set to launch in the mid-2020s, the Nancy Grace Roman Space Telescope will explore the mysteries of dark energy, dark matter, and exoplanets, ushering in a new era of detailed cosmic surveys and discoveries. Credit: NASA ============================================================= NASA’s Nancy Grace Roman Space Telescope, featuring a state-of-the-art camera, will significantly enhance our cosmic exploration, providing insights into dark energy, dark matter, and distant exoplanets through detailed, expansive surveys. The primary instrument for NASA’s Nancy Grace Roman Space Telescope is a sophisticated camera that will survey the cosmos from the outskirts of our solar system all the way out to the edge...

Unofficial reports of 10 antihelium nuclei smacking into the International Space Station have inspired theoretical physicists to speculate beyond our current models in search of an explanation. While a small handful of cosmic particles might appear trivial, the signature of the antihelium shower is strange enough for researchers to treat the event like a rainstorm in a desert. In their recently published analysis, scientists from the Perimeter Institute for Theoretical Physics in Canada and Johns Hopkins University in the US make a case for considering physics outside of the currently accepted Standard Model, going as far as suggesting dark matter...

A long-term Hubble Space Telescope study of the Draco dwarf galaxy’s stars suggests dark matter is concentrated at the galaxy’s center, supporting the density cusp theory. This finding challenges earlier observations and improves our understanding of dark matter’s role in galaxy formation. (Artist’s concept.) Credit: SciTechDaily.com =================================================================================== The Hubble Space Telescope’s longevity is an asset in gaining clarity about the universe’s invisible glue. When theory and observations favor different results, how can astronomers determine which one is more feasible? Increasing confidence in one theory over another oftentimes requires building a richer dataset to improve current models and lower uncertainties. A...

JWST deep field vs hubble This region of space, viewed first iconically by Hubble and later by JWST, shows an animation that switches between the two. Both images still have fundamental limitations, as they were acquired from within our inner Solar System, where the presence of zodiacal light influences the noise floor of our instruments, and cannot easily be removed.Credit: NASA, ESA, CSA, STScI, Christina Williams (NSF’s NOIRLab), Sandro Tacchella (Cambridge), Michael Maseda (UW-Madison); Processing: Joseph DePasquale (STScI); Animation: E. Siegel ======================================================================================= KEY TAKEAWAYS: * The darkest night skies, both from Earth as well as from interplanetary space, aren’t completely...

A recent study that presents new challenges to the existence of dark matter suggests gravity may be able to exist even in the absence of mass. Although all life on Earth experiences its effects daily, gravity remains one of the great mysteries of modern physics. Now, a new study published by Dr. Richard Lieu with The University of Alabama in Huntsville (UAH) proposes that the gravitational effects observed in galaxies and clusters may be the result of what he likens to topological defects in the universe, a theory that does not require the inclusion of dark matter to explain phenomena...

Two dwarf galaxies (top and bottom) orbit the much larger Andromeda galaxy. DAVID DAYAG/WIKIMEDIA COMMONS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ When astronomers fret about the “missing satellites problem,” they’re not talking about spacecraft in Earth orbit. Their problem is much bigger: For decades, far fewer dwarf galaxies have been seen orbiting the Milky Way and other large galaxies than predicted by models of galaxy formation. But now, two groups of astronomers have found evidence for not just a sufficient number of satellite galaxies to satisfy the simulations—but too many. “Maybe we’ve oversolved the problem,” says Marcel Pawlowski, an astronomer at the Leibniz Institute for...

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...