Mysterious Brief Pulse Detected From Outer Space Baffles Astronomers
The discovery has raised major new questions by scientists using the Arecibo radio telescope in Puerto Rico over what caused a split-second burst of radio waves. It marks the first time that a so-called "fast radio burst" has been detected using an instrument other than the Parkes radio telescope in Australia, stated the findings by an international team of astronomers, and published July 10 in The Astrophysical Journal. "The brightness and duration of this event, and the inferred rate at which these bursts occur, are all consistent with the properties of the bursts previously detected by the Parkes telescope in Australia," said Laura Spitler, lead author of the new paper.
The unusual pulse was detected on Nov. 2, 2012, at the Arecibo Observatory, a National Science Foundation-sponsored facility that boasts the world's largest and most sensitive radio telescope, with a radio-mirror dish spanning 305 meters and covering about 20 acres.
Although a handful of such events have been recorded by scientists using the Parkes Observatory, the lack of any similar findings by other facilities has led to speculation that the Australian instrument might have been picking up signals originating from sources on or near Earth. "Our result is important because it eliminates any doubt that these radio bursts are truly of cosmic origin," said Victoria Kaspi, an astrophysics professor at McGill University in Montreal and Principal Investigator for the pulsar-survey project that detected this fast radio burst. "The radio waves show every sign of having come from far outside our galaxy - a really exciting prospect."
However, exactly what might be causing such radio bursts represents a major new enigma for astrophysicists, and fodder for much speculation, according to UK MailOnline. Some possibilities include a range of exotic astrophysical objects, such as evaporating black holes, mergers of neutron stars, or flares from magnetars -- a type of neutron star with extremely powerful magnetic fields.
"Another possibility is that they are bursts much brighter than the giant pulses seen from some pulsars," noted James Cordes, a professor of astronomy at Cornell University and co-author of the new study.
The discovery was made as part of the Pulsar Arecibo L-Band Feed Array (PALFA) survey, which aims to find a large sample of pulsars and to discover rare objects useful for probing fundamental aspects of neutron star physics and testing theories of gravitational physics.
Meanwhile, efforts are currently under way to detect radio bursts using radio telescopes that can observe broad swaths of the sky to help identify them.
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