Latest news with #VLA
The Hindu
6 hours ago
- Science
- The Hindu
IIST team discovers radio emission with circular polarisation near a massive young protostar
An international team led by astronomers from the Indian Institute of Space Science and Technology (IIST) here has discovered radio emission with a special property known as circular polarisation near a massive young protostar that is still forming about 4,500 light years from earth. [Protostar refers to the earliest known stage of a star when it is still accumulating gas and dust material from its surroundings.] The discovery linked to IRAS 18162-2048, a massive protostar in the Milky Way galaxy, opens an exciting window into scientists' understanding of how massive stars form, astronomers at the IIST said on Thursday. Circular polarisation occurs when electric and magnetic field vectors of electromagnetic waves—in this case radio waves—rotate in a circle about the direction in which the waves travel through space. This emission offers the first direct clue to the strength of magnetic fields in the immediate neighbourhood of a protostar, they said. The findings have been published in The Astrophysical Journal Letters under the title 'First Detection of Circular Polarization in Radio Continuum Toward a Massive Protostar.' In the early stage, the protostar can also eject high-velocity material in opposite directions, known as a bipolar jet. 'Massive protostars' evolve to have mass more than 8 to 10 times that of the Sun. Protostellar jets According to the astronomers, IRAS 18162-2048 powers one of the largest and brightest known protostellar jets in the Milky Way, the HH80-81 jet. It is believed that the magnetic field and rotation in the protostellar system are responsible for the ejection of the jet. While a magnetic field has been imaged from the jet earlier, this is the first time that hints of it have been detected directly from this massive protostar, according to the IIST. Strong magnetic fields have been observed earlier in low-mass protostars that go on to form stars like the Sun. But measuring such fields around massive protostars has remained elusive, until now. Much harder to study 'Massive protostars are much harder to study. The circular polarisation we are looking for is very faint and sporadic, making such measurements very challenging,' Amal George Cheriyan from the IIST, lead author of the paper, said in a statement. The radio observations were carried out using the National Radio Astronomy Observatory's (NRAO) Karl G. Jansky Very Large Array (VLA) in the U.S. 'This is the first inference of the magnetic field strength using circular polarisation in radio waves from a massive protostar,' said Sarita Vig of the IIST who conceptualised the work. Remarkable result 'The detection of circular polarisation is an exceptionally rare and challenging feat even in active galactic nuclei (AGNs), where conditions are extreme, but better investigated,' Nirupam Roy from the Indian Institute of Science (IISc), Bengaluru, said. Samir Mandal of the IIST noted that observing the phenomenon in the environment of a massive protostar, which lies buried in dense gas and dust, is even more difficult, making this result remarkable. The new data has allowed researchers to infer that the magnetic field near the protostar is roughly 100 times stronger than the Earth's magnetic field. They also support a long-standing theory that powerful jets from stars and black holes are driven by the same magnetic engine.
The Hindu
25-06-2025
- Business
- The Hindu
Google DeepMind unveils on-device robotics model
Google DeepMind has unveiled a Gemini Robotics on-device Vision Language Action (VLA) model that can run locally on robotic devices. The AI model is built for general purpose tasks and can run without the internet. This is Google's first VLA model that has made available for fine-tuning. Developers can sign up for the tester programme and access the software kits. This new model comes two months after the search giant released its Gemini Robotics model based on Gemini 2.0's multimodal reasoning and real-world understanding of the physical world. The flagship model can run both on-device and on the cloud, and is built for bi-pedal robots. The model can also be customised for different robotic form factors. 'While we trained our model only for ALOHA robots, we were able to further adapt it to bi-arm Franka FR3 robot and the Apollo humanoid robot by Apptronik,' the company said in a blog post. With the bi-arm Franks, the VLA model can perform other tasks like folding clothes or work on industrial belt assembly tasks too.
Hans India
12-06-2025
- Science
- Hans India
Nasa's Chandra detects powerful black hole jet during universe's 'cosmic noon'
In a remarkable cosmic discovery, NASA's Chandra X-ray Observatory has detected a surprisingly powerful jet emerging from a supermassive black hole located 11.6 billion light-years from Earth. This black hole existed during "cosmic noon"—a period roughly three billion years after the Big Bang, when galaxies and black holes grew at record rates. Working alongside the Karl G. Jansky Very Large Array (VLA), astronomers captured X-ray and radio data that reveal the jet's extraordinary reach—over 300,000 light-years—and the extreme speeds of the particles within it, approaching 99% the speed of light. The black hole's jet became visible because it collided with the dense sea of cosmic microwave background (CMB) radiation—the ancient light left over from the Big Bang. These high-speed electrons boosted CMB photons into the X-ray range, enabling Chandra to detect them despite the vast distance. Two black holes, designated J1405+0415 and J1610+1811, were confirmed to have jets traveling at relativistic speeds. Remarkably, the jet from J1610+1811 carries nearly half as much energy as the light from gas orbiting the black hole, highlighting its immense power. Because of special relativity, jets moving toward Earth appear brighter, creating a detection bias. The research team overcame this challenge by developing a novel statistical model that factors in these relativistic effects. Through thousands of simulations, they estimated the jets' viewing angles—approximately 9° and 11° from Earth's line of sight. These findings were presented by lead researcher Jaya Maithil of the Center for Astrophysics | Harvard & Smithsonian at the 246th meeting of the American Astronomical Society in Anchorage, Alaska. The results will be published in The Astrophysical Journal, with a preprint already available online. NASA's Marshall Space Flight Center manages the Chandra program, with science operations led from the Smithsonian Astrophysical Observatory's Chandra X-ray Center in Cambridge, Massachusetts.
NDTV
10-06-2025
- Science
- NDTV
Black Hole With Powerful Jet Illuminated By Universe's 'Oldest Light' Spotted
Using NASA's Chandra X-ray Observatory and Karl G Jansky Very Large Array (VLA), astronomers have spotted a powerful jet from a black hole situated in the distant universe that is being illuminated by the leftover glow from the Big Bang -- the oldest light in the universe. Researchers observed the black hole and its jet at a period they call "cosmic noon," which occurred about three billion years after the universe began. The black hole is located 11.6 billion light-years from Earth, when the cosmic microwave background (CMB) was much denser than it is now. During this time, most galaxies and supermassive black holes were growing faster than at any other time during the history of the universe. "As the electrons in the jets fly away from the black hole, they move through the sea of CMB radiation and collide with microwave photons," NASA stated, adding: "These collisions boost the energy of the photons up into the X-ray band, allowing them to be detected by Chandra even at this great distance, which is shown in the inset." The jets extending from these black holes can extend millions of light-years in length. They are exceedingly bright because when particles approach the speed of light, they give off a tremendous amount of energy and behave in weird ways that Albert Einstein predicted. Two other black holes Additionally, the researchers confirmed the existence of two different black holes with jets over 300,000 light-years long. Situated 11.6 billion and 11.7 billion light-years away, particles in one jet are moving at between 95 per cent and 99 per cent of the speed of light (called J1405+0415) and the other at between 92 per cent and 98 per cent of the speed of light (J1610+1811). In January, scientists stumbled upon a supermassive black hole, located a whopping 12.9 billion light-years from Earth, with its jet pointing straight at us. Named J0410-0139, the black hole has a mass of about 700 million Suns and is one of the oldest of its kind that scientists have ever observed. When one of these jets points directly at Earth, scientists call the black hole system a blazar. Notably, a jet racing at near-light speed but angled away from us can appear just as bright as a slower jet pointed directly at Earth.
Yahoo
28-05-2025
- Politics
- Yahoo
Upgraded Very Large Array Telescope Will Spot Baby Solar Systems—If It's Funded
New Mexico's Plains of San Agustin are otherworldly: Silence, sand and sharp plants reign on the valley floor. Knobbly volcanic rock rises above. Pronghorns' legs and jackrabbits' ears break up the landscape. And so, too, does one of the world's largest telescopes. The plains house the aptly named Very Large Array (VLA)—a radio telescope made of 27 different antennas, each of which looks like a home satellite dish on steroids. In the otherwise empty desert, they spread into a Y shape that can extend 22 miles end-to-end. When the antennas are pointed at the same thing in the sky at the same time, they function together as one large telescope, simulating an instrument as wide as the distance between the dishes. In this case, then, images from the VLA have as much resolution as they would if it were a single telescope 22 miles wide: high definition, in other words. The VLA became iconic, and inspirational to a generation of astronomers, thanks to the movie Contact, in which Jodie Foster's character uses the array to hear an alien communication. [Sign up for Today in Science, a free daily newsletter] The VLA's antennas, the true stars of the film, simultaneously look like they don't belong in the landscape and also like they've always been here. They haven't, of course, but their construction began in the 1970s, making the VLA the oldest instrument in the portfolio of the National Radio Astronomy Observatory (NRAO). This federally-funded organization builds, maintains and operates radio telescopes that any astronomer—regardless of their institutional affiliation or citizenship—can apply to use. But the VLA, now in its middle age, is due for a replacement. After all these decades, astronomers want something shiny, fully modern and more capable: a new build with all the bells and whistles rather than a charming old Colonial that's been remodeled piecemeal. NRAO is working on that, planning the VLA's proposed successor: the Next-Generation Very Large Array (ngVLA). (Astronomers may be scientifically creative, but they are linguistic straight shooters.) On a Friday afternoon in late April, the organization gathered political leaders together, alongside scientists and engineers, to unveil a prototype antenna—one that will be cloned a couple of hundred times to make up the future ngVLA. It loomed on the plains just beyond the partygoers, standing alongside its predecessors, the old and the new in stereo with each other. 'The amount that technology has advanced since the VLA was created is amazing,' says Jill Malusky, NRAO's news and public information manager. 'A VLA antenna and an ngVLA antenna look very different because they are.' Guests wandered near the antennas, checking out a spread of food that included a sculpture, made in the medium of watermelon, of a radio telescope antenna. A chamber quartet played in the background, a single fern fronting them, with an open bar lubricating the event. It was fancy—for science. But for astronomers, the ngVLA is a big deal, and the event was intended, in part, to bolster the political support needed to make it happen. At the moment, it's a proposed project—and still requires final funding. 'Having a physical antenna we can point to, and test, to prove the value of this project is such a milestone,' Malusky says. 'It makes it all more real.' Representing an orders-of-magnitude improvement to the VLA that would complement other radio telescopes in the U.S. and abroad, the ambitious project has the enthusiastic yes of the astronomical community. But whether big-science telescopes, radio or otherwise, will survive the current funding environment remains a dark matter. That uncertainty is part of why NRAO's event elicited a spectrum of emotions for Malusky. 'It's a mix of excitement and trepidation,' she says. 'Can we get people invested in the potential of a major project that is still gathering resources and just over a decade to fruition?' That Friday afternoon, Tony Beasley, director of NRAO, stood at the front of a hardy event tent and faced the prototype. Its dish was made up of shiny panels assembled into an octagon. From its bottom edge, supportive struts held up a secondary reflecting surface and a receiver (basically the radio version of an optical telescope's camera) that looked a bit like the spaceship Foster's character boarded in Contact. The antenna, about as wide as a bowling lane is long, has been designed to collect radio waves from space—beamed from stars that are being born or dying, the stuff between stars, and more. As radio light comes in, it will hit the main dish and bounce up to the secondary reflector and then the receiver, which will catch the waves and turn them into digital signals that will then be sent to computers. As a start, the prototype dish will hook up to VLA's aging ones and gather data alongside them—it will be an apprentice of sorts. 'You see one antenna out there,' said Beasley, directing the audience's attention beyond the tent, which was being shaken by the wind to such an extent that people also cast their eyes upward to assess its structural integrity. NRAO ultimately plans to build 262 more antennas and spread them across the U.S., with their numbers concentrated in the Southwest. Of those antennas, Beasley continued, '192 of them will be visible from where I'm standing right here.' Together, the ngVLA's antennas could pick up a cell-phone signal from 500 billion kilometers (more than 310 billion miles) away (although that wouldn't be the most likely find). That means it could detect an Android embedded in the Oort Cloud, the collection of comets that makes up the outer part of the solar system. The future telescope's resolution should be high enough to pass a no-glasses eye exam in New York City if the chart of letters were placed in Los Angeles. That precision gives it scientific latitude, allowing it to address some of astronomers' highest-priority questions, such as how planets come to be and how solar systems like ours form. 'You could, say, probe a cloud that is forming planets and find out where the planets are—like individual gaps in the cloud that the planets are carving out,' says David Kaplan, an astronomer and physics professor at the University of Wisconsin–Milwaukee. Of all the radio telescopes out there, the ngVLA would be the planetary 'flagship' for star and planet formation, Kaplan says. At high radio frequencies and big antenna separations, 'it would be the only game in town.' The ngVLA will also look for the organic molecules and chemical conditions of new solar systems that might someday spur life. It will show how galaxies come together and evolve, use the Milky Way's center to test ideas about how gravity works and investigate how stars develop. And it will hunt black holes and their outbursts. Given those varied abilities, the telescope was highly ranked in astronomers' 'decadal survey,' a yearslong process in which the astronomical community takes stock of its most valued scientific questions and assesses which future telescopes are best suited to find some answers. Funding from agencies such as the National Science Foundation (NSF), which bankrolls NRAO, typically follows the survey's recommendations. The survey recommended the ngVLA as a top priority. 'It can change the landscape,' says Matt Dobbs, a physicist at McGill University, who studies the origin and evolution of the universe and worked on the survey alongside Kaplan. NRAO hopes to start construction on the ngVLA in 2029, with initial operations beginning in 2033. The possibility is a bright spot for American radio astronomy. The VLA is more than 40 years old; the Green Bank Telescope, completed in 2001, is more than 20. And NRAO's latest instrument, the Atacama Large Millimeter/submillimeter Array, opened 12 years ago. The latter two, though not new, aren't going anywhere, as far as anyone knows. But they do different kinds of scientific analyses than the VLA does and the ngVLA will. The new telescope does, though, have a whippersnapper nipping at its heels. Another future radio observatory, called the Deep Synoptic Array 2000 (DSA-2000), is planning an order of magnitude more dishes than the ngVLA—2,000 of them. But each will be only around 16 feet across, whereas ngVLA's dishes will measure 60 feet. DSA-2000 will also work at a different radio frequency range than the ngVLA. DSA-2000's development is also moving faster than that of the VLA's successor, though, in large part, that is because the former has relied on private funding more than federal resources, as the ngVLA's prototyping has. In taking a step back from dependence on the NSF, the DSA-2000 crew might be on to something. Just days before the ngVLA ceremony, the NSF canceled more than 400 active grants; one day before, the agency's then director Sethuraman Panchanathan resigned. 'This is a pivotal moment for our nation in terms of global competitiveness,' he said in his goodbye letter. 'NSF is an extremely important investment to make U.S. scientific dominance a reality. We must not lose our competitive edge.' No one knows what the future of NSF-funded astronomy, let alone NSF-funded radio astronomy, looks like. President Donald Trump hasn't said much about that particular domain yet. But not building the ngVLA could put that edge in jeopardy. Dobbs, though, holds out hope for the U.S.'s role in radio astronomy's future, in part because of the propulsion of its past. 'The United States has everything it needs to make that project a reality,' he adds. Whether it will do so, though, requires gathering more data from the future. After all, it's bad luck to count your antennas before they hatch. Dobbs has been putting his focus on smaller radio telescopes, such as one called the Canadian Hydrogen Intensity Mapping Experiment (CHIME) and its successor, acronymed CHORD. Both map how hydrogen was distributed in the early universe and detect fast radio bursts. Their antennas are cheap(ish), their overall footprint small, and their ambition is limited to specific science—in this case, gas maps. At the prototype-antenna unveiling, then, it made sense that there was a liminal feeling to what was otherwise a celebratory gathering. And it was conspicuous that representatives from NSF, the agency that would fund the telescope's construction and operation, weren't there, which Beasley said was the case 'for various reasons.' Chris Smith, interim director of the NSF's division of astronomical sciences, did send a letter to be read to the wined-and-dined crowd. 'NSF funded this development not just to ensure the technical feasibility of the advanced capabilities of ngVLA,' he wrote. It also supported the prototype as 'a way of creating new innovations in the field of radio astronomy.' And that may be true. But those who gathered at NRAO's event also hope, specifically, that the ngVLA, a receptacle for optimism about the future of radio astronomy in the U.S., will sprout from this dry ground. 'It starts with a single step,' Beasley said at the event—in this case, a single antenna.
