Mysterious Bursts of Radio Waves May Offer New Clues to Contents of Universe
An international team of researchers has detected a mysterious burst of radio waves originating from billions of light years away, the source of which are not entirely clear. However, writing about the discovery in the journal Science, the scientists say they have ruled out terrestrial sources.
The four fast radio bursts likely hail from cosmological distances when the universe was just half its current age based on their brightness and distance, the researchers report, adding that the burst energetics indicate they are derived from an extreme astrophysical event involving relativistic objects such as neutron stars or black holes.
According to study lead Dan Thornton, a Ph.D. student at England's University of Manchester and Australia's Commonwealth Scientific and Industrial Research Organisation, the findings point to massive events involving large amounts of mass or energy as the source.
"A single burst of radio emission of unknown origin was detected outside our Galaxy about six years ago but no one was certain what it was or even if it was real, so we have spent the last four years searching for more of these explosive, short-duration radio bursts," he said in a press release. "This paper describes four more bursts, removing any doubt that they are real."
In all, the radio bursts last for mere milliseconds, with the furthest one observed located 11 billion light years away.
Despite the relative newness of the discovery and the limited number of identified events, the researchers explain they are constantly occurring.
"The bursts last only a tenth of the blink of an eye," Michael Kramer, director of the Max-Planck Institute and Manchester professor, said. "With current telescopes we need to be lucky to look at the right spot at the right time. But if we could view the sky with 'radio eyes' there would be flashes going off all over the sky every day."
In fact, there should be one of these signals going off every 10 seconds, the researchers found.
In terms of the origins of the emissions, co-author Professor Matthew Bailes from the Swinburne University of Technology in Melbourne believes magnetic neutron stars, known as 'magnetars,' are to blame.
"Magnetars can give off more energy in a millisecond than our Sun does in 300,000 years and are a leading candidate for the burst," he explained.
The study results, the researchers further stated, further provide a new way of finding out the properties of space between the Earth and where the bursts occurred.
"We are still not sure about what makes up the space between galaxies, so we will be able to use these radio bursts like probes in order to understand more about some of the missing matter in the universe," author Ben Stappers from Manchester's School of Physics and Astronomy said. "We are now starting to use Parkes and other telescopes, like the Lovell Telescope of the University of Manchester, to look for these bursts in real time."
The team, which included researchers from the United Kingdom, Germany, Italy, Australia and the United States used the CSIRO Parkes 64-meter radio telescope in Australia to obtain their results.