Latest news with #PieterVanDokkum
Yahoo
6 days ago
- Science
- Yahoo
This Could Be The First Witnessed Birth of a Supermassive Black Hole
Supermassive black holes represent one of the biggest head-scratchers in the Universe. These behemoths weighing millions to tens of billions of Suns lurk at the center of just about every galaxy – the gravitational heart around which stars and planets and clouds of shimmering gas whirl in an intricate dance. What we don't know is how these giants are born. Do they grow slowly, a gradual accumulation of mass from a seed the size of a single star's core? Or do they form directly from the collapse of giant clouds of material in space so dense that they cannot fight the inward pull of their own gravity? A new discovery might – at least partially – give us an answer. A pair of galaxies whose light has traveled for 8.3 billion years contains what astronomers believe is a supermassive black hole in the act of forming. If this is the case, it is the first time we have seen this process in action, a vital and unprecedented piece of the supermassive black hole formation puzzle. Related: Earliest Black Hole Ever Seen Discovered at The Dawn of Time "We think we're witnessing the birth of a supermassive black hole – something that has never been seen before," says astronomer Pieter van Dokkum of Yale University in the US. This 'smoking gun' was found in a pair of galaxies in the act of colliding, oriented so that their configuration resembles a figure-eight, or infinity symbol. The researchers have named the object the Infinity galaxy, and it really is an oddity discovered in a search for oddities in the JWST COSMOS-Web survey of the Universe. Each of the galaxy's two lobes has its own brightly glowing nucleus, with a supermassive black hole lurking therein. However, where the two lobes overlap and intersect, a third brightly glowing blob can be seen. The researchers carefully studied this blob in multiple wavelengths, and were stunned to find the signatures of a third supermassive black hole, smack bang between the two lobes of the Infinity galaxy. "We asked ourselves: how can we make sense of this?" van Dokkum says. A careful, closer analysis of the material around the anomalous black hole suggested that it was newly formed, sitting in an extended region of hot, shocked gas. This suggests a new mechanism for black hole formation, based on the direct collapse model. "In this case, two disk galaxies collided, forming the ring structures of stars that we see. During the collision, the gas within these two galaxies shocks and compresses. This compression might just be enough to have formed a dense knot that then collapsed into a black hole," van Dokkum explains. "While such collisions are rare events, similarly extreme gas densities are thought to have been quite common at early cosmic epochs, when galaxies began forming." Related: A Supermassive Black Hole Is on a Collision Course With The Milky Way Galactic collisions have long been proposed as one mechanism whereby supermassive black holes can grow. When the two objects merge, their central black holes are inexorably gravitationally drawn together, eventually colliding and merging to form a bigger black hole. Such galaxy collisions are also thought to be a crucial part of how galaxies grew in the early Universe; the Milky Way is thought to have undergone multiple such mergers. This hypothesis is sound, but it doesn't answer the question about how the less-massive, but still supermassive, black holes at the centers of these galaxies formed. A growing body of evidence supports the direct collapse model, but we've not seen the process in action. The Infinity galaxy is a little more halfway through the Universe's 13.8-billion-year history, but the early Universe was full of dense clouds of hydrogen gas that could have rammed into each other, creating shocked knots of huge amounts of material in a very similar way. The discovery, therefore, is a compelling argument for the direct collapse model at the very beginning of the Universe. "This is as close to a smoking gun as we're likely ever going to get," van Dokkum says. Two papers outlining the discovery have been submitted to The Astrophysical Journal Letters. They can be found on arXiv here and here. Related News Surprise Cosmic Clouds Likened to Finding Ice Cubes in a Volcano Is 3I/ATLAS 'Comet' an Alien Probe? These Are The Signs to Look For. Early Forms of Cells Could Form in The Lakes of Saturn's Moon Titan Solve the daily Crossword
Yahoo
19-07-2025
- Science
- Yahoo
Bizarre "Infinity Galaxy" Could Hold the Secrets of Supermassive Black Holes
Astronomers using data collected by the James Webb Space Telescope have discovered a spectacular cosmic object they're calling the "Infinity Galaxy." The site of an epic head-on collision between two galaxies, it could harbor the secrets to how the heaviest black holes in the universe, the supermassive black holes found at the hearts of galaxies, are born and reach their unbelievable masses — masses extreme enough to organize trillions of stars around them. "Everything is unusual about this galaxy. Not only does it look very strange, but it also has this supermassive black hole that's pulling a lot of material in," Pieter van Dokkum, lead author of a new study published in the Astrophysical Journal Letters, said in a statement about the work. "As an unexpected bonus, it turns out that both galaxy nuclei also have an active supermassive black hole," van Dokkum added. "So, this system has three confirmed active black holes: two very massive ones in both of the galaxy nuclei, and the one in between them that might have formed there." The singularity-studded object was found by searching through public data collected in the COSMOS-Web survey, which is designed to document the evolution of galaxies, with data gathered on 800,000 realms and counting. In an image taken with the Webb, two bright spots represent the nuclei of each of the two colliding galaxies, both surrounded by their own ring of stars. This lends it the shape of an infinity symbol, hence its memorable name. What's most striking, though, is what appears between them, revealed in follow-up observations: an enormous supermassive black hole swimming in a sea of ionized gas. It's estimated to contain a mass equivalent to a million times that of our own Sun — and it's still actively growing. "It likely didn't just arrive there, but instead it formed there. And pretty recently," van Dokkum said. "We think we're witnessing the birth of a supermassive black hole — something that has never been seen before." This could be some of the most compelling evidence yet of black holes forming by directly collapsing into a singularity from a huge, heavy cloud of gas. The origins of supermassive black holes are one of the great mysteries of cosmology. They undeniably exist, forming the heart of the largest galaxies, including our own Milky Way — but how they form and gain such unbelievable heft is still hotly debated; the heaviest black holes may weigh hundreds of billions of solar masses. The most well-known way that black holes are born is through the collapse of a very massive star that explodes in a supernova. This might spawn a black hole with several to a hundred times the mass of the Sun, maybe even a thousand. Then, give one of these stellar-mass black holes hundreds of millions to billions of years to devour matter that falls into it, or merge with other black holes, and it might reach a supermassive stature. Astronomers, however, have observed black holes boasting millions of solar masses while existing just 400 million years after the Big Bang, which simply isn't enough time for one to reach its size by gradually accreting matter. That points to another possibility called the "heavy seed theory," explains van Dokkum, "where a much larger black hole, maybe up to one million times the mass of our Sun, forms directly from the collapse of a large gas cloud." This would've been facilitated by the hot conditions of the early universe, allowing a gas cloud to collapse into one large object instead of forming numerous smaller stars. "It's not clear that this direct-collapse process could work in practice," van Dokkum said. But there's compelling reason to believe that the Infinity Galaxy is home to a black hole born through this exact process. The best clue is the central supermassive black hole's velocity, which matches up with the surrounding gas, strongly suggesting it formed right where we're seeing it. If it formed elsewhere in the cosmos and barged into the mix, the velocity would be significantly higher. What astronomers think happened, then, is that when the constituent two galaxies collided, the gas contained in them compressed to form a "dense knot," van Dokkum said, "which then collapsed into a black hole." "We can't say definitively that we have found a direct collapse black hole," van Dokkum concluded. "But we can say that these new data strengthen the case that we're seeing a newborn black hole, while eliminating some of the competing explanations." More on black holes: Scientists Detect Sign of Something Impossible Out in Deep Space Solve the daily Crossword
The National
17-07-2025
- Science
- The National
Mysterious black hole spotted between colliding galaxies confounds researchers
A mysterious black hole spotted between two galaxies that are crashing into each other is challenging existing theories on how these powerful cosmic objects are formed. Researchers behind the study were surprised as black holes are typically found at the centre of galaxies, not floating between them. The discovery was made using Nasa's James Webb Space Telescope (JWST), which captured images of two distant galaxies merging in a collision. Released on Tuesday, the image shows the black hole appearing as a bright glow between the galaxies. 'Finding a black hole that's not in the nucleus of a massive galaxy is in itself unusual, but what's even more unusual is the story of how it may have gotten there,' said Dr Pieter van Dokkum, professor of astronomy and physics at Yale University and lead author of the study. 'It likely didn't just arrive there, but instead it formed there, and pretty recently. 'In other words, we think we're witnessing the birth of a supermassive black hole, something that has never been seen before.' Scientists have been studying black holes and how they form for decades as they remain one of the most mysterious objects in the universe and are so powerful that not even light can escape them. In this latest discovery, researchers believe that the black hole was formed without the usual step of a dying star collapsing. There are some leading theories on how supermassive black holes found in the centre of galaxies are formed. One says that they begin as leftovers of massive stars and when a star starts dying, it explodes and collapses under its own gravity to form a black hole. The newly formed small black holes then feed on gas and merges with others to become a supermassive, a process that can take billions of years. But this theory does not explain how some black holes appear fully formed in the early universe. This led scientists to consider the 'direct collapse' theory, a rare situation where a dense cloud of gas collapses directly into a black hole, skipping the usual step of a dying star. This latest discovery by the JWST could be the strongest evidence yet of that process. 'By looking at the data from the Infinity Galaxy, we think we've pieced together a story of how this could have happened here,' said Prof van Dokkum. 'Two disk galaxies collide, forming the ring structures of stars that we see. During the collision, the gas within these two galaxies shocks and compresses. 'This compression might just be enough to form a dense knot, which then collapsed into a black hole. 'We can't say definitively that we have found a direct collapse black hole. But we can say that these new data strengthen the case that we're seeing a newborn black hole, while eliminating some of the competing explanations.' The findings are part of a growing list of discoveries made by the telescope since its launch on Christmas Day in 2021. It is a joint project by Nasa and the European and Canadian space agencies to study the early universe and learn more about the Solar System. The telescope has already captured detailed images of galaxies forming less than 400 million years after the Big Bang. It has also provided new clues on the atmospheres of exoplanets, planets that orbit stars outside the Solar System. Other Nasa telescopes have made breakthrough discoveries, including the TESS space telescope, which observed a 'super-Earth planet' that has been flashing a repeated signal from 154 light-years away. The planet, named TOI-1846 b, is almost twice the size of Earth. It orbits a red dwarf, small and cool stars, that is about 40 per cent smaller in size and mass than the Sun. Scientists are hoping to use the JWST to study the planet's atmosphere, as its unique instruments would be capable of detecting any possible signs of water, vapour, methane, carbon dioxide or other gases.
Yahoo
31-05-2025
- General
- Yahoo
'Cosmic miracle!' James Webb Space Telescope discovers the earliest galaxy ever seen
When you buy through links on our articles, Future and its syndication partners may earn a commission. The James Webb Space Telescope (JWST) excels at a lot of things, but there are two things it does better than any other scientific instrument in human history: spotting early galaxies and breaking its own records!Now, the $10 billion NASA space telescope has done both things again, detecting a galaxy that existed just 280 million years after the Big Bang, a feat that the team behind this research has dubbed a "cosmic miracle."Currently, as the earliest and most distant galaxy ever detected, this "the mother of all early galaxies," this new JWST discovery has been fittingly designated "MoM z14." "First and foremost, at the moment, this is the most distant object known to humanity. That title changes every so often, but I find it is always cause for pause and reflection," team member and Yale University professor of Astronomy and Physics Pieter van Dokkum told "MoM z14 existed when the universe was about 280 million years old - we're getting quite close to the Big Bang. "Just to put that in context, sharks have been around on Earth for a longer timespan!" Since it began sending data back to Earth in the summer of 2022, the JWST has excelled in detecting galaxies at so-called "high redshifts." Redshift refers to the phenomenon of the wavelength of light from distant and thus early sources being stretched and shifted toward the "red end" of the electromagnetic spectrum as it traverses expanding space. The earlier and thus further away an object is, the greater the redshift. Prior to the discovery of MoM z14, the galaxy holding the title of earliest and distant was JADES-GS-z14-0, which existed just 300 million years after the Big Bang, or around 13.5 billion years ago. This previous record galaxy has a redshift of z =14.32, while MoM z14 has a redshift of z = 14.44. There is a wider context to the observation of MoM z14 than the fact that it has broken the record for earliest known galaxy by 20 million years, though, as van Dokkum explained. "The broader story here is that JWST was not expected to find any galaxies this early in the history of the universe, at least not at this stage of the mission," van Dokkum said. "There are, very roughly, over 100 more relatively bright galaxies in the very early universe than were expected based on pre-JWST observations."Also, in addition to detecting this new, earliest, and most distant galaxy, the team was able to determine some of its characteristics using the JWST. The researchers were able to determine that MoM z14 is around 50 times smaller than the Milky Way. The team also measured emission lines from the galaxy, indicating the presence of elements like nitrogen and carbon. "The emission lines are unusual; it indicates that the galaxy is very young, with a rapidly increasing rate of forming new stars," van Dokkum said. "There are also indications that there is not much neutral hydrogen gas surrounding the galaxy, which would be surprising: the very early universe is expected to be filled with neutral hydrogen. "That needs even better spectra and more galaxies, to investigate more fully." The presence of carbon and nitrogen in MoM z14 indicates that there are earlier galaxies to be discovered than this 13.52 billion-year-old example. That is because the very earliest galaxies in the universe and their stars were filled with the simplest elements in the cosmos, hydrogen and helium. Later galaxies would be populated by these heavier elements, which astronomers somewhat confusingly call "metal," as their stars forged them and then dispersed them in supernova explosions. "MoM z14 is not one of the very first objects that formed in the universe, as the stars in those galaxies are composed of hydrogen and helium only - we would not see carbon or nitrogen," van Dokkum said. "It could be part of the first wave of formation of 'normal' galaxies, that is, the first galaxies that have elements like nitrogen and carbon - but we've thought that before!" Related Stories: — Is our universe trapped inside a black hole? This James Webb Space Telescope discovery might blow your mind —James Webb Space Telescope finds our Milky Way galaxy's supermassive black hole blowing bubbles (image, video) — James Webb Space Telescope sees early galaxies defying 'cosmic rulebook' of star formation As for finding even earlier galaxies than MoM z14 and perhaps even detecting that first generation, van Dokkum is confident that the JWST is up to the task. He explained: "The JWST continues to push the boundary beyond where we thought it was, and at this point I would not be surprised if we find galaxies at z =15 or z =16!" For now, van Dokkum and the rest of this team, led by Rohan Naidu of MIT's Kavli Institute for Astrophysics and Space Research, can celebrate breaking new ground in our understanding of the early cosmos."In a program like this, the whole team is always hoping for a 'miracle,' that is, that some of the candidate extremely early galaxies actually pan out and are not 'mirages,' objects whose colors look like extremely early objects," van Dokkum concluded. "While we were hoping for some very early objects, I don't think any of us expected to break the redshift record!" A pre-peer-reviewed version of the team's research is published on the paper repository site arXiv.
