Dying star could be behind immensely powerful radio bursts 'heard' live
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Version 0 of 1. A fleeting but immensely powerful celestial signal has been “heard” live for the first time, radio astronomers in Australia have announced, bringing scientists a step closer to discovering its mysterious origins. “Fast radio bursts” last only milliseconds but produce more energy in that time than the sun does in 24 hours. Their source has baffled astronomers since 2007, when researchers first detected “a bright millisecond radio burst of extragalactic origin” buried in a 90-hour pulsar survey taken at the Parkes observatory in western New South Wales. Since then just seven more bursts have been identified, but only ever picked up weeks after the signal was received. Last May, for the first time, astronomers caught a live one. “It was chaos,” said Emily Petroff, the Swinburne University PhD student leading the project that detected the burst. An email alert went out 10 seconds after the discovery. Telescopes in California, the Canary Islands, Chile, Germany, Hawaii and India scrambled to point their receivers at the same patch of sky where the signal was heard. Astronomers quickly made optical, infrared, ultraviolet and x-ray observations of its traces. News of the discovery was published on Tuesday in the Monthly Notices of the Royal Astronomical Society. One theory suggests the bursts could be an energetic flare emitted by a dead star with a particularly strong magnetic field. More enticingly, it could also be evidence of a massive star five billion light years away undergoing a cataclysmic collision or collapse, and forming a black hole. “This would essentially be a death signal, the signal of a black hole forming,” Petroff said. Around 10,000 fast radio bursts are thought reach our galaxy each day, but telescopes can only survey a small patch. “We’re very rarely pointing in the right direction at the right time,” Petroff said. “Every once in a while we just get super lucky.” At the very least, this latest detection gives fast radio burst hunters some clues about where to look. “We’ve set the trap. Now we just have to wait for another burst to fall into it.” Petroff said the radio signals “essentially encode information in them of all the things they’ve pass through between their emitter and our telescope”. That means figuring out the trajectory of the signal and its exact age might yield answers to even deeper questions: about the matter that exists between galaxies, even the weight of the universe itself. That work is threatened by an earthly source: science funding cuts by Australia’s federal government have hit the Parkes observatory hard. The dish that helped broadcast the 1969 moon landing could shut within two years “without substantial, long-term external investment,” senior astronomers have warned. “As it stands, in the field of fast radio bursts, Parkes is by far the world leader,” Petroff said. If it did close, “it would be very difficult to keep operating on the same level”. |