An international team of scientists has detected mysterious bursts of radio waves originating from cosmological distances when the Universe was just half its current age.
CSIRO’s Parkes radio telescope, which has been used to confirm a population of Fast Radio Bursts, is shown superimposed on an image showing the distribution of gas in our Galaxy; an artist’s impression of a single fast radio burst is shown located well away from the Galactic plane emission (Swinburne Astronomy Productions)
The burst energetics indicates that they originate from an extreme astrophysical event involving relativistic objects such as neutron stars or black holes.
“The findings pointed to some extreme events involving large amounts of mass or energy as the source of the radio bursts,” said Dan Thornton, a PhD student at the University of Manchester, UK, who is a lead author of a paper published in the journal Science.
“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. This paper describes four more bursts, removing any doubt that they are real. The radio bursts last for just a few milliseconds and the furthest one that we detected was several billion light years away.”
The results also suggest that there should be one of these signals going off every 10 seconds.
“The bursts last only a tenth of the blink of an eye. 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,” said co-author Prof Michael Kramer from the Max-Planck-Institut für Radio Astronomie.
The astronomers used the CSIRO Parkes 64-m radio telescope in Australia to make the discovery.
They suggest the origin of these explosive bursts may be from magnetic neutron stars, known as magnetars.
“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,” explained co-author Prof Matthew Bailes from the Swinburne University of Technology in Melbourne.
The results also provide a way of finding out the properties of space between the Earth and where the bursts occurred.
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Bibliographic information: Thornton D. et al. 2013. A Population of Fast Radio Bursts at Cosmological Distances. Science, vol. 341, no. 6141, pp. 53-56; doi: 10.1126/science.1236789
