Mysterious cosmic signals carry a clue to their origins

illustration of a magnetar
BIG BURST  Starquakes on highly magnetic neutron stars known as magnetars (illustrated) are one possible source of extragalactic bursts of radio waves, new research suggests. 
Enigmatic blasts of cosmic radio waves are dropping hints about their origins. A recently discovered burst appears to originate in or near a relatively young stellar neighborhood in another galaxy, researchers report online December 2 in Nature.
This fast radio burst, FRB 110523, has much in common with previously detected bursts (SN: 8/9/14, p. 22). It lasted for just a few milliseconds, did not repeat and originated well outside the Milky Way — in this case, up to 6 billion light-years away in the constellation Aquarius. But the burst provided an extra piece of information. The radio waves showed signs of having run into strong magnetic fields and dense blobs of plasma, often found near young stars, astrophysicist Kiyoshi Masui of the University of British Columbia in Canada and colleagues report.
The team found the burst in 2011 data recorded by the Green Bank Telescope in West Virginia. The strength of the magnetic fields and the density of the plasma encountered by the signal are greater than what lies within the Milky Way or in intergalactic space, suggesting that FRB 110523 originated close to a magnetized nebula or within the core of its host galaxy. Possible sources include starquakes on highly magnetic neutron stars (the cores of dead massive stars), the delayed formation of a black hole after a supernova or ferocious blasts from pulsars, all of which were recently hinted at by a hiccup seen in another radio burst 
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