Latest news with #ALMA
Yahoo
3 days ago
- Science
- Yahoo
Scientists may have found a powerful new space object: 'It doesn't fit comfortably into any known category'
When you buy through links on our articles, Future and its syndication partners may earn a commission. A bewilderingly powerful mystery object found in a nearby galaxy and only visible so far in millimeter radio wavelengths could be a brand new astrophysical object unlike anything astronomers have seen before. The object has been named 'Punctum,' derived from the Latin pūnctum meaning "point" or "dot," by a team of astronomers led by Elena Shablovinskaia of the Instituto de Estudios Astrofísicos at the Universidad Diego Portales in Chile. Shablovinskaia discovered it using ALMA, the Atacama Large Millimeter/submillimeter Array. "Outside of the realm of supermassive black holes, Punctum is genuinely powerful,' Shablovinskaia told Astronomers don't know what it is yet — only that it is compact, has a surprisingly structured magnetic field, and, at its heart, is an object radiating intense amounts of energy. "When you put it into context, Punctum is astonishingly bright — 10,000 to 100,000 times more luminous than typical magnetars, around 100 times brighter than microquasars, and 10 to 100 times brighter than nearly every known supernova, with only the Crab Nebula surpassing it among star-related sources in our galaxy," Shablovinskaia said. Punctum is located in the active galaxy NGC 4945, which is a fairly close neighbor of our Milky Way galaxy, located 11 million light-years away. That's just beyond the confines of the Local Group. Yet, despite this proximity, it cannot be seen in optical or X-ray light but rather only millimeter radio wavelengths. This has only deepened the mystery, although the James Webb Space Telescope (JWST) has yet to take a look at the object in near- and mid-infrared wavelengths. What could Punctum be? Its brightness remained the same over several observations performed in 2023, meaning it is not a flare or some other kind of transitory phenomenon. Millimeter-wave radiation typically comes from cold objects such as young protoplanetary disks and interstellar molecular clouds. However, very energetic phenomena such as quasars and pulsars can also produce radio waves through synchrotron radiation, wherein charged particles moving at close to the speed of light spiral around magnetic field lines and radiate radio waves. What we do know about Punctum is that based on how strongly polarized its millimeter light is, it must possess a highly structured magnetic field. And so, Shablovinskaia believes what we are seeing from Punctum is synchrotron radiation. Objects with strong polarization tend to be compact objects, because larger objects have messy magnetic fields that wash out any polarization. Perhaps that synchrotron radiation is being powered by a magnetar, the team believes, which is a highly magnetic pulsar. However, while a magnetar's ordered magnetic field fits the bill, magnetars (and regular pulsars for that matter) are much fainter at millimeter wavelengths than Punctum is. Supernova remnants such as the Crab Nebula, which is the messy innards blasted into space of a star that exploded in 1054AD, are bright at millimeter wavelengths. The trouble is that supernova remnants are quite large — the Crab Nebula itself is about 11 light-years across — whereas Punctum is clearly a much smaller, compact object. "At the moment, Punctum truly stands apart — it doesn't fit comfortably into any known category," said Shablovinskaia. "And honestly, nothing like this has appeared in any previous millimeter surveys, largely because, until recently, we didn't have anything as sensitive and high-resolution as ALMA." There is the caveat that Punctum could just be an outlier: an extreme version of an otherwise familiar object, such as a magnetar in an unusual environment, or a supernova remnant interacting with dense material. For now, though, these are just guesses lacking supporting evidence. It is quite possible that Punctum is indeed the first of a new kind of astrophysical object that we haven't seen before simply because only ALMA can detect them. In the case of Punctum, it is 100 times fainter than NGC 4945's active nucleus that is being energized by a supermassive black hole feeding on infalling matter. Punctum probably wouldn't have been noticed at all in the ALMA data if it wasn't for its exceptionally strong polarization. Further observations with ALMA will certainly help shed more light on what kind of object Punctum is. The observations that discovered Punctum were actually focused on NGC 4945's bright active core; it was just happenstance that Punctum was noticed in the field of view. Future ALMA observations targeting Punctum instead would be able to go to much lower noise levels without worrying about the galaxy's bright core being over-exposed, and it could also be observed across different frequencies. The greatest help could potentially come from the JWST. If it can see an infrared counterpart, then its greater resolution could help identify what Punctum is. "JWST's sharp resolution and broad spectral range might help reveal whether Punctum's emission is purely synchrotron or involves dust or emission lines," said Shablovinskaia. For now, it's all ifs and buts, and all we can say for sure is that astronomers have a genuine mystery on their hands that has so far left them feeling flummoxed. "In any case," concluded Shablovinskaia, "Punctum is showing us that there is still a lot to discover in the millimeter sky.' A paper describing the discovery of Punctum has been accepted by the journal Astronomy & Astrophysics, and a pre-print is available on Solve the daily Crossword
Yahoo
3 days ago
- Science
- Yahoo
Early galaxy looked like lumpy ‘cosmic grapes'
A cluster of 'Cosmic Grapes' is challenging current theoretical models on how galaxies formed during the universe's earliest eons. After combining observations from the Atacam Large Millimeter/submillimeter Array (ALMA) and the James Webb Space Telescope, astronomers now possess an unprecedented look at about 15 gargantuan 'star-forming clumps' inside a single rotating disk that formed only 900 million years after the big bang. 'Early galaxies form through dark matter and gas assembly, evolving into dynamically hot, chaotic structures driven by mergers and feedback,' the international research team explained in their Nature Astronomy study published on August 7. 'By contrast, remarkably smooth, rotating disks are observed in massive galaxies only 1.4 billion years after the Big Bang, implying rapid dynamical evolution.' Understanding how this cosmic evolution unfolded requires the ability to study young galaxies—something previously made difficult by limitations in observational tools' sensitivity and spatial resolution. Even with the Hubble Space Telescope's groundbreaking abilities, the 'Cosmic Grapes' galaxy only appeared as a smooth, singular disk-like formation. Using more recent and advanced projects like JWST and ALMA, astronomers were able to refocus on the mystery target with some help from a cosmic neighbor. According to a study announcement from the National Radio Astronomy Observatory, the Cosmic Grapes structure 'happened to be perfectly magnified by a foreground galaxy cluster through gravitational lensing.' The opportunity allowed researchers to devote over 100 hours of quality telescope time to the individual system, making it one of the early universe's most extensively analyzed galaxies. Instead of the individual disk seen in Hubble's images, the exponentially greater resolution from JWST and ALMA showcased a wholly different situation—a rotating galaxy stuffed with giant, lumpy stellar formations resembling the vineyard fruit. The reveal is also the first time that astronomers successfully linked an early galaxy's smaller internal structures to their larger, collective rotation. The data was so detailed that they even managed to achieve a spatial resolution of 10 parsecs, or about 30 light-years. What's particularly striking is that Cosmic Grapes isn't an oddball or extreme example given what astronomers understand of galactic evolution. Instead, it exists on the standard, main sequence of galaxies when it comes to attributes like star formations, mass, chemical composition, and size. This suggests many of the era's galaxies that have been previously documented as smooth may more resemble the clumpy, dynamic structure seen through JWST and ALMA. 'Because existing simulations fail to reproduce such a large number of clumps in rotating galaxies at early times, this discovery raises key questions about how galaxies form and evolve,' the National Radio Astronomy Observatory's announcement explained. 'It suggests that our understanding of feedback processes and structure formation in young galaxies may need significant revision.' Solve the daily Crossword
Yahoo
4 days ago
- Science
- Yahoo
Scientists may have found a powerful new space object: 'It doesn't fit comfortably into any known category'
When you buy through links on our articles, Future and its syndication partners may earn a commission. A bewilderingly powerful mystery object found in a nearby galaxy and only visible so far in millimeter radio wavelengths could be a brand new astrophysical object unlike anything astronomers have seen before. The object has been named 'Punctum,' derived from the Latin pūnctum meaning "point" or "dot," by a team of astronomers led by Elena Shablovinskaia of the Instituto de Estudios Astrofísicos at the Universidad Diego Portales in Chile. Shablovinskaia discovered it using ALMA, the Atacama Large Millimeter/submillimeter Array. "Outside of the realm of supermassive black holes, Punctum is genuinely powerful,' Shablovinskaia told Astronomers don't know what it is yet — only that it is compact, has a surprisingly structured magnetic field, and, at its heart, is an object radiating intense amounts of energy. "When you put it into context, Punctum is astonishingly bright — 10,000 to 100,000 times more luminous than typical magnetars, around 100 times brighter than microquasars, and 10 to 100 times brighter than nearly every known supernova, with only the Crab Nebula surpassing it among star-related sources in our galaxy," Shablovinskaia said. Punctum is located in the active galaxy NGC 4945, which is a fairly close neighbor of our Milky Way galaxy, located 11 million light-years away. That's just beyond the confines of the Local Group. Yet, despite this proximity, it cannot be seen in optical or X-ray light but rather only millimeter radio wavelengths. This has only deepened the mystery, although the James Webb Space Telescope (JWST) has yet to take a look at the object in near- and mid-infrared wavelengths. What could Punctum be? Its brightness remained the same over several observations performed in 2023, meaning it is not a flare or some other kind of transitory phenomenon. Millimeter-wave radiation typically comes from cold objects such as young protoplanetary disks and interstellar molecular clouds. However, very energetic phenomena such as quasars and pulsars can also produce radio waves through synchrotron radiation, wherein charged particles moving at close to the speed of light spiral around magnetic field lines and radiate radio waves. What we do know about Punctum is that based on how strongly polarized its millimeter light is, it must possess a highly structured magnetic field. And so, Shablovinskaia believes what we are seeing from Punctum is synchrotron radiation. Objects with strong polarization tend to be compact objects, because larger objects have messy magnetic fields that wash out any polarization. Perhaps that synchrotron radiation is being powered by a magnetar, the team believes, which is a highly magnetic pulsar. However, while a magnetar's ordered magnetic field fits the bill, magnetars (and regular pulsars for that matter) are much fainter at millimeter wavelengths than Punctum is. Supernova remnants such as the Crab Nebula, which is the messy innards blasted into space of a star that exploded in 1054AD, are bright at millimeter wavelengths. The trouble is that supernova remnants are quite large — the Crab Nebula itself is about 11 light-years across — whereas Punctum is clearly a much smaller, compact object. "At the moment, Punctum truly stands apart — it doesn't fit comfortably into any known category," said Shablovinskaia. "And honestly, nothing like this has appeared in any previous millimeter surveys, largely because, until recently, we didn't have anything as sensitive and high-resolution as ALMA." There is the caveat that Punctum could just be an outlier: an extreme version of an otherwise familiar object, such as a magnetar in an unusual environment, or a supernova remnant interacting with dense material. For now, though, these are just guesses lacking supporting evidence. It is quite possible that Punctum is indeed the first of a new kind of astrophysical object that we haven't seen before simply because only ALMA can detect them. In the case of Punctum, it is 100 times fainter than NGC 4945's active nucleus that is being energized by a supermassive black hole feeding on infalling matter. Punctum probably wouldn't have been noticed at all in the ALMA data if it wasn't for its exceptionally strong polarization. Further observations with ALMA will certainly help shed more light on what kind of object Punctum is. The observations that discovered Punctum were actually focused on NGC 4945's bright active core; it was just happenstance that Punctum was noticed in the field of view. Future ALMA observations targeting Punctum instead would be able to go to much lower noise levels without worrying about the galaxy's bright core being over-exposed, and it could also be observed across different frequencies. The greatest help could potentially come from the JWST. If it can see an infrared counterpart, then its greater resolution could help identify what Punctum is. "JWST's sharp resolution and broad spectral range might help reveal whether Punctum's emission is purely synchrotron or involves dust or emission lines," said Shablovinskaia. For now, it's all ifs and buts, and all we can say for sure is that astronomers have a genuine mystery on their hands that has so far left them feeling flummoxed. "In any case," concluded Shablovinskaia, "Punctum is showing us that there is still a lot to discover in the millimeter sky.' A paper describing the discovery of Punctum has been accepted by the journal Astronomy & Astrophysics, and a pre-print is available on Solve the daily Crossword
Forbes
06-08-2025
- Science
- Forbes
Planet Formation Theory Is Still Ensnared By A Chicken Or Egg Problem
In the rush to understand the formation history of solar systems like ours, one big conundrum still ensnares this field of research. That is, how protostellar disks form their very first planets. We don't yet know how that first planet gets formed, Nienke van der Marel an astronomer at Leiden University in The Netherlands, tells me in her office. We understand how clumping can be caused by physical forces within the disk once there's a planet in that disk, van der Marel tells me, but the biggest question is still how that first planet formed. Ongoing observations by the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile's Northern Atacama Desert are largely responsible for the lion's share of our current knowledge about how protoplanetary disks form from millimeter-sized particles and grow into full-fledged planetary systems like ours. In 2013, using some of the first ALMA observations van der Marel and colleagues detected the existence of a dust trap in a protoplanetary disk around the young A-type star Oph-IRS 48, located some 400 light-years away in the Northern constellation of Ophiuchus. A dust trap is a location where millimeter-sized pebbles, are concentrated in one part of the disk, and where they can continue to grow all the way from planetesimals (planetary building blocks ranging from a few km to a few hundred km in diameter) to full-fledged planets. That first planet will carve a gap along its orbit and then at the outer edge of that gap, you naturally get a maximum in the density and a bump in the gas density, says van der Marel. So now, the pebbles that come from the outer disk still drift inwards, but then at that maximum pressure location, they get trapped, she says. But as soon as these particles reach typical pebble sizes (1 mm across), they will start to experience drag forces from the gas in the disk and rapidly move inwards toward the star, says van der Marel. Disappearing Pebbles So, within a hundred years, any pebble that you form out here in the outer region of the disk has moved all the way inwards and onto the star and is lost; it doesn't have time to continue growing all the way to planetesimals, says van der Marel. So, you need something that stops the pebbles from drifting inwards, she says. And the phenomenon that was proposed to stop it was a dust trap, says van der Marel. Planetary Disk Pressure Bumps 'Pressure bumps' or 'dust traps' present in the disk will halt these inward moving pebbles and trap them, says van der Marel. This whole idea creates a major chicken or egg problem, because if you need a planet to create dust traps, then dust traps are necessary to form planetesimals and planets, she says. Alternative Scenarios If indeed planets are the only source of dust traps, then we do have a chicken or egg problem to form the first planet, Olja Panic, an astrophysicist at the University of Leeds in the U.K., tells me in Reykjavik. But recent research has been directed towards identifying possible scenarios under which these dust traps can arise without the need for planets to cause them, says Panic. This could include various types of gravitational disk instabilities, whether generated from a passing star or during the disk's earliest formation. It is also possible that there are other mechanisms that create the first dust traps, such as magnetic fields, ionization structures (which would arrange molecules so that they have a net electrical charge), or even planetary snowlines. That is, regions in a young planetary disk where temperatures are so cold that water, ammonia, carbon monoxide or even methane can freeze into ice grains. Some researchers posit that this increase in ice density might even trigger the formation of gas giant planets like Jupiter. The idea is that these first dust traps would then concentrate these planetary pebbles until the first planet forms within the dust trap. But that has yet to be confirmed observationally. When Might This Problem Be Solved? Although ALMA's array of 66 telescopes work have allowed astronomers to see incredible detail in these disks of gas and dust around young stars, future telescopes will reveal even more detail about how these stars spawn planets. In the coming decades, a lot of new telescopes will teach us more about the composition of exoplanets which may also tell us how they form, says van der Marel. Just like ALMA, the Next Generation Very Large Array (NGVLA) in New Mexico is another up and coming radio array which will observe at even longer wavelengths where we can trace even larger dust grains, she says. That may help us to understand where most planet formation takes place, says van der Marel. Is our solar system an anomaly? We don't have the data right now to say for certain whether we are an anomaly or not, says van der Marel.
Yahoo
02-08-2025
- Science
- Yahoo
Is life widespread throughout the cosmos? Complex organic molecules found in planet-birthing disk
When you buy through links on our articles, Future and its syndication partners may earn a commission. Astronomers have detected signs of complex organic molecules, the precursors to the building blocks of life as we know it, in a planet-forming disk around a distant star. The findings imply that the chemical seeds of life are constructed in space and are then spread to young or newly forming planets. Using the Atacama Large Millimeter/ submillimeter Array (ALMA), a system of radio telescopes in Chile, the team detected traces of 17 complex organic molecules in the protoplanetary disc of V883 Orionis, a young star located around 1,305 light-years away in the constellation of Orion. V883 Orionis is an infant star, or protostar, that is estimated to be just 500,000 years old, and it's in the active phase of gathering mass and forming planets. If 0.5 million years old seems ancient, consider that our middle-aged sun is about 4.6 billion years old. Complex organic molecules are molecules that have more than five atoms, at least one of which is carbon. They have been seen around sites of star and planet formation previously. However, the compounds discovered around V883 Orionis include the first tentative detections of ethylene glycol and glycolonitrile, compounds that are considered precursors to the building blocks of life. For instance, glycolonitrile is a precursor of the amino acids glycine and alanine, as well as the nucleobase adenine, one of the building blocks of DNA and RNA. The find could therefore provide a missing link in the story of the evolution of molecules around young stars, accounting for the period between the initial formation of stars and the growth of planets in their surrounding protoplanetary disks. "Our finding points to a straight line of chemical enrichment and increasing complexity between interstellar clouds and fully evolved planetary systems," team leader Abubakar Fadul, a scientists at the Max Planck Institute for Astronomy (MPIA) in Germany, said in a statement. A cosmic chemical assembly line Stars start life when overdense clumps in vast clouds of interstellar gas and dust collapse under their own gravity. This creates a protostar that continues to gather matter from its natal envelope until it has sufficient mass to trigger the fusion of hydrogen to helium in its core. That's the nuclear process that defines what a main-sequence star is. As this proceeds, material around the budding star flattens out into a swirling donut of gas and dust called a protoplanetary disk, from which planets will eventually emerge. The transition from protostar to a young main-sequence star is a violent one, replete with intense radiation, shocked gas, and gas being ejected from the protoplanetary disk. This is thought to be deleterious to the continued existence of complex chemicals built during earlier stages of the protostar's existence. This has led to the development of a so-called "reset scenario" that sees the chemicals needed for life forming at later stages in the existence of the protoplanetary disk, as planets, asteroids, and comets are formed. However, the new discovery suggests that this reset scenario is unnecessary. "Now it appears the opposite is true," said team member and MPIA scientist Kamber Schwarz. "Our results suggest that protoplanetary disks inherit complex molecules from earlier stages, and the formation of complex molecules can continue during the protoplanetary disk stage." The team theorizes that the period between the energetic protostellar phase and the establishment of a protoplanetary disk would be too brief for complex organic molecules to form in detectable amounts. The upshot of this is that the conditions that predefine biological processes may not be restricted to individual planetary systems, but may be more widespread. Because the chemical reactions that create complex organic molecules proceed better in colder conditions, they could occur in icy dust that later gathers to form large bodies. That means these molecules could remain hidden in dust, rock and ice in young planetary systems, only accessible when heating by the central star warms those materials. This is something seen in our own solar system when comets from the outer region of our planetary system pass close to the sun, creating cometary tails and halos called comas. Though V883 Orionis hasn't yet reached the mass needed to achieve nuclear fusion, there is a heating mechanism available in this young system for a similar thawing to occur: When material falls to the star, facilitating its growth, bursts of intense radiation are triggered. "These outbursts are strong enough to heat the surrounding disk as far as otherwise icy environments, releasing the chemicals we have detected," said Fadul. It's fitting that ALMA, an array of 66 radio telescopes located in the Atacama Desert region of northern Chile, has been integral to probing deeper into the disk around V883 Orionis. It was this array, after all, that first discovered the water snow line in the disk of V883 Orionis back in 2016. "While this result is exciting, we still haven't disentangled all the signatures we found in our spectra," Schwarz said. "Higher resolution data will confirm the detections of ethylene glycol and glycolonitril and maybe even reveal more complex chemicals we simply haven't identified yet." Related Stories: — The mystery of how strange cosmic objects called 'JuMBOs' went rogue — These mysterious objects born in violent clashes between young star systems aren't stars or planets — James Webb Space Telescope dives into the atmosphere of a mystery rogue planet or failed star Fadul suggested that astronomers need to look at light from stars like V883 Orionis and its protoplanetary disk in other wavelengths of the electromagnetic spectrum to find even more evolved molecules. "Who knows what else we might discover?" Fadul concluded. The team's research is available as a preprint on the paper repository arXiv. Solve the daily Crossword
