Latest news with #Caltech
Yahoo
3 days ago
- Science
- Yahoo
What Astronomers Just Discovered Between Galaxies Changes Everything
For decades, scientists have known that a massive chunk of the universe's ordinary matter was missing. Not dark matter, the elusive substance that doesn't interact with light, but regular, everyday matter made of atoms. And now, thanks to a brilliant use of cosmic radio signals, that mystery may finally be solved. In a new study published in Nature Astronomy, astronomers used fast radio bursts (FRBs)—brief, millisecond-long blasts of energy from deep space—to detect where all that missing matter was hiding: in the vast stretches between galaxies, known as the intergalactic medium. These FRBs are powerful. Though short-lived, they emit as much energy in one burst as the sun does in 30 years. When they pass through space, they act like cosmic flashlights, lighting up the otherwise invisible gas that floats between galaxies. The team measured how the light from 69 FRBs slowed as it moved through this matter, allowing them to "weigh" the fog they passed through. "It's like we're seeing the shadow of all the baryons," explained Caltech assistant professor Vikram Ravi, using the scientific term for this ordinary matter. "With FRBs as the backlight, we now know roughly where the rest of the matter in the universe is hiding." The results show about 76 percent of the universe's baryonic matter exists in this intergalactic fog. Meanwhile, 15 percent of the baryonic matter surrounds galaxies in halos and just 9 percent resides inside the galaxies themselves. This breakthrough was made possible by telescopes like Caltech's Deep Synoptic Array and Australia's Square Kilometre Array Pathfinder, which helped localize the FRBs' origins. Caltech's upcoming DSA-2000 radio telescope, set to detect 10,000 FRBs per year, could be the key to even deeper cosmological insights. For astronomers, it's a milestone moment—one that brings us closer to understanding not just where we come from, but how the universe is truly structured. What Astronomers Just Discovered Between Galaxies Changes Everything first appeared on Men's Journal on Jun 17, 2025
Yahoo
3 days ago
- Science
- Yahoo
Astronomers just found the universe's ‘missing matter'
If you purchase an independently reviewed product or service through a link on our website, BGR may receive an affiliate commission. There's been a lot of discussion over the years about what the universe is made up of. While some argue that dark matter is holding it together, while others argue dark matter doesn't exist, despite us possibly detecting dark matter a time or two. What is more intriguing, though, is that astronomers believe the universe is missing matter, and now they say they've found evidence of it. This matter was considered 'missing' because of how thinly it was spread among the various galaxies and halos of the universe. Because it is so diffuse, it's exceptionally hard to account for. But in a new study published in Nature Astronomy, astronomers from Caltech and the Center for Astrophysics | Harvard & Smithsonian (CfA) say they have detected the matter. Today's Top Deals Best deals: Tech, laptops, TVs, and more sales Best Ring Video Doorbell deals Memorial Day security camera deals: Reolink's unbeatable sale has prices from $29.98 Additionally, they say that they've thoroughly accounted for all the universe's missing matter. According to a statement shared by Caltech, the researchers relied on fast radio bursts (FRBs) to help illuminate the matter that lies between those distant FRBs and us here on Earth. 'The FRBs shine through the fog of the intergalactic medium, and by precisely measuring how the light slows down, we can weigh that fog, even when it's too faint to see,' Liam Connor, an assistant professor at Harvard and lead author on the new study explained. In total, the team looked at 69 FRBs, ranging in distance from around 11.74 million to 9.1 billion light-years away from us. FRB 20230521B, which is located 9.1 billion light-years away, is now the most distant FRB ever recorded. Despite having detected more than a thousand FRBs, we've only managed to pinpoint around one hundred or so to their specific host galaxies. Other attempts to detect the missing matter had only hinted at its existence hiding among the holes and halos of the universe. However, by relying on the FRBs, the researchers were able to find evidence of the matter. These findings will help us better understand the universe and how galaxies grow. They could also help us unravel some of the greatest mysteries of the early universe, including how the universe expanded has expanded so quickly since the Big Bang. And researchers say this is just the beginning of the use of FRBs in cosmology. A future radio telescope from Caltech will help find and localize up to 10,000 FRBs per year, which should dramatically enhance our understanding of these distant radio bursts. More Top Deals Amazon gift card deals, offers & coupons 2025: Get $2,000+ free See the
Yahoo
3 days ago
- Science
- Yahoo
Invisible no more: Scientists map 76% of ordinary matter lost between galaxies
For years, the universe held onto a secret that left cosmologists half of the universe's ordinary matter, responsible for building everything from protons and stars to planets and people, has remained elusive due to its diffuse nature. Scientists had considered it 'missing'—until now.' Now, in a breakthrough study, astronomers from Caltech and the Center for Astrophysics | Harvard & Smithsonian (CfA) have managed to directly detect this missing matter using fast radio bursts (FRBs)—brief, powerful flashes of radio waves originating from distant galaxies. These cosmic signals, lasting just milliseconds, serve as precise probes, lighting up the otherwise invisible intergalactic medium. As these FRBs travel billions of light-years to reach Earth, they pass through clouds of ionized gas between galaxies. The radio waves slow down ever so slightly depending on how much matter they encounter along the way. By measuring this delay, known as dispersion, scientists can calculate the amount of invisible matter in the FRBs' path. "The FRBs shine through the fog of the intergalactic medium, and by precisely measuring how the light slows down, we can weigh that fog, even when it's too faint to see," says Liam Connor, assistant professor at Harvard and lead author of the study. The study analyzed 69 well-localized FRBs, each with a host galaxy and known distance. One of the FRBs studied, dubbed FRB 20230521B, is located a staggering 9.1 billion light-years away, making it the most distant fast radio burst ever recorded. Although astronomers have detected over a thousand FRBs to date, only around a hundred have been accurately traced back to their host galaxies. This localization is crucial, as knowing both the origin and distance of an FRB is essential for using it to map the matter it passed through, making these select few key to the current study. Of these, 39 were discovered using the Deep Synoptic Array (DSA)-110, a network of 110 radio antennas in California designed specifically to detect and pinpoint FRBs. The remaining FRBs came from global observatories, including Australia's Square Kilometre Array Pathfinder. Instruments at Hawaii's W. M. Keck Observatory and the Palomar Observatory near San Diego helped determine the distance to each FRB's host galaxy. Their findings confirm that roughly 76 percent of ordinary matter resides in the intergalactic medium, thinly spread across space. Another 15 percent lies in gaseous halos surrounding galaxies, while only a small fraction is found inside galaxies themselves, in stars, or cold galactic gas."It's like we're seeing the shadow of all the baryons, with FRBs as the backlight," said Vikram Ravi, assistant professor of astronomy at Caltech. "If you see a person in front of you, you can find out a lot about them. But if you just see their shadow, you still know that they're there and roughly how big they are." This distribution of matter aligns with predictions made by advanced cosmological simulations but has never been confirmed observationally—until now. The findings also open new avenues for probing fundamental physics. For instance, they may help determine the mass of subatomic particles called neutrinos. While the standard model of particle physics assumes neutrinos have no mass, real-world observations suggest otherwise. Knowing their precise mass could unlock physics beyond current theories. According to Ravi, this is just the beginning for FRBs in cosmology. A new project, Caltech's DSA-2000 radio telescope, currently in development for the Nevada desert, is expected to localize up to 10,000 FRBs each year—dramatically expanding their role in probing the universe's structure. The study, published in Nature Astronomy, was funded by the National Science Foundation.
Straits Times
4 days ago
- Science
- Straits Times
Astronomers locate universe's 'missing' matter
An artist's conception depicts warm, thin gas in a vast region between galaxies - called the intergalactic medium, in this handout illustration image obtained by REUTERS. Blue highlights denser regions of the cosmic web, transitioning to redder light for void areas. Courtesy of Jack Madden, IllustrisTNG, Ralf Konietzka, Liam Connor/CfA/Handout via REUTERS/Illustration The Deep Synoptic Array (DSA), a network of 110 radio telescopes, point to the sky at Caltech's Owen Valley Radio Observatory near Bishop, California, U.S., in this undated photograph released on June 16, 2025. Vikram Ravi/Caltech/OVRO/Handout via REUTERS WASHINGTON - The universe has two kinds of matter. There is invisible dark matter, known only because of its gravitational effects on a grand scale. And there is ordinary matter such as gas, dust, stars, planets and earthly things like cookie dough and canoes. Scientists estimate that ordinary matter makes up only about 15% of all matter, but have long struggled to document where all of it is located, with about half unaccounted for. With the help of powerful bursts of radio waves emanating from 69 locations in the cosmos, researchers now have found the "missing" matter. It was hiding primarily as thinly distributed gas spread out in the vast expanses between galaxies and was detected thanks to the effect the matter has on the radio waves traveling through space, the researchers said. This tenuous gas comprises the intergalactic medium, sort of a fog between galaxies. Scientists previously had determined the total amount of ordinary matter using a calculation involving light observed that was left over from the Big Bang event roughly 13.8 billion years ago that initiated the universe. But they could not actually find half of this matter. "So the question we've been grappling with was: Where is it hiding? The answer appears to be: in a diffuse wispy cosmic web, well away from galaxies," said Harvard University astronomy professor Liam Connor, lead author of the study published on Monday in the journal Nature Astronomy. The researchers found that a smaller slice of the missing matter resides in the halos of diffuse material surrounding galaxies, including our Milky Way. Ordinary matter is composed of baryons, which are the subatomic particles protons and neutrons needed to build atoms. "People, planets and stars are made of baryons. Dark matter, on the other hand, is a mysterious substance that makes up the bulk of the matter in the universe. We do not know what new particle or substance makes up dark matter. We know exactly what the ordinary matter is, we just didn't know where it was," Connor said. So how did so much ordinary matter end up in the middle of nowhere? Vast amounts of gas are ejected from galaxies when massive stars explode in supernovas or when supermassive black holes inside galaxies "burp," expelling material after consuming stars or gas. "If the universe were a more boring place, or the laws of physics were different, you might find that ordinary matter would all fall into galaxies, cool down, form stars, until every proton and neutron were a part of a star. But that's not what happens," Connor said. Thus, these violent physical processes are sloshing ordinary matter around across immense distances and consigning it to the cosmic wilderness. This gas is not in its usual state but rather in the form of plasma, with its electrons and protons separated. The mechanism used to detect and measure the missing ordinary matter involved phenomena called fast radio bursts, or FRBs - powerful pulses of radio waves emanating from faraway points in the universe. While their exact cause remains mysterious, a leading hypothesis is that they are produced by highly magnetized neutron stars, compact stellar embers left over after a massive star dies in a supernova explosion. As light in radio wave frequencies travels from the source of the FRBs to Earth, it becomes dispersed into different wavelengths, just as a prism turns sunlight into a rainbow. The degree of this dispersion depends on how much matter is in the light's path, providing the mechanism for pinpointing and measuring matter where it otherwise would remain unfound. Scientists used radio waves traveling from 69 FRBs, 39 of which were discovered using a network of 110 telescopes located at Caltech's Owens Valley Radio Observatory near Bishop, California, called the Deep Synoptic Array. The remaining 30 were discovered using other telescopes. The FRBs were located at distances up to 9.1 billion light-years from Earth, the farthest of these on record. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). With all the ordinary matter now accounted for, the researchers were able to determine its distribution. About 76% resides in intergalactic space, about 15% in galaxy halos and the remaining 9% concentrated within galaxies, primarily as stars or gas. "We can now move on to even more important mysteries regarding the ordinary matter in the universe," Connor said. "And beyond that: what is the nature of dark matter and why is it so difficult to measure directly?" REUTERS Join ST's Telegram channel and get the latest breaking news delivered to you.
Gizmodo
4 days ago
- Science
- Gizmodo
Astronomers Just Solved the Mystery of the Universe's Missing Matter
Decades ago, astronomers estimated that 'ordinary' matter (basically everything that isn't dark matter or dark energy) makes up 5% of the universe. There was just one problem—they had no idea where most of it was. Astronomers from the Center for Astrophysics Harvard & Smithsonian (CfA) and the California Institute of Technology (Caltech) have tracked down the universe's 'missing' matter. Fast radio bursts (FRBs) indicate that over three-quarters of ordinary matter, officially called baryonic matter, exists in the form of hot, low-density gas between galaxies. With this data, they claim to have documented the first detailed measurements of ordinary matter's distribution throughout the universe. 'The decades-old 'missing baryon problem' was never about whether the matter existed,' CfA astronomer Liam Connor said in a CfA statement. 'It was always: Where is it? Now, thanks to FRBs, we know: three-quarters of it is floating between galaxies in the cosmic web.' Connor and his colleagues explain their discovery in a study published today in Nature Astronomy. Technically, baryonic matter is matter made of protons and neutrons. However, astronomers often use the term to refer to all matter made of atoms, which makes up everything that isn't dark matter or dark energy. 'A small fraction of baryons are in stars and the interstellar medium within galaxies,' the researchers wrote in the study. The interstellar medium is the space between star systems. Previous research suggested that much of the remaining baryonic matter was gas spread throughout the intergalactic medium—the space between galaxies. But because 'this diffuse ionized gas is notoriously difficult to measure,' the team added, scientists couldn't confirm how much of the gas existed or exactly where it was. In the new study, the researchers relied on FRBs—quick, bright radio signals from faraway galaxies. FRBs slow down when they travel through intergalactic gas. By measuring this decrease in speed, the team could infer how much gas the signal had traversed. They investigated 60 FRBs ranging from a galaxy 11.74 million light years away to one approximately 9.1 billion light years away. The latter emitted the most distant FRB known to science, designated FRB 20230521B. By studying FRBs, scientists confirmed that around 76% of all baryonic matter exists in the IGM, 15% in galaxy halos, and another small fraction in stars or cold galactic gas. Cosmological simulations had previously suggested this distribution, but the recent study provides direct evidence, shedding light on the movement of matter across the universe. 'Baryons are pulled into galaxies by gravity, but supermassive black holes and exploding stars can blow them back out—like a cosmic thermostat cooling things down if the temperature gets too high,' said Connor, who is the lead author of the study. 'Our results show this feedback must be efficient, blasting gas out of galaxies and into the IGM.' 'We're beginning to see the Universe's structure and composition in a whole new light, thanks to FRBs,' added Caltech astronomer and co-author Vikram Ravi. 'These brief flashes allow us to trace the otherwise invisible matter that fills the vast spaces between galaxies.' With increasingly powerful telescopes expected to detect thousands of FRBs, who knows what other mysteries might soon come to light?
