Astronomers Have Tracked a Repeating Radio Signal Across Space to an Unexpected Origin
MICHELLE STARR | 7 JAN 2020
A mysterious repeating radio signal from space revealed last year is now the fifth fast radio burst to be tracked back to its source galaxy.
It's a location unlike any of the others, and astronomers are having to rethink their previous assumptions about how these signals are generated.
The origin of this repeating signal is a spiral galaxy, located 500 million light-years from Earth, making it the closest known source of what we call fast radio bursts (FRBs) yet.
And the FRBs are emanating specifically from a region just seven light-years across - a region that's alive with star formation.
"This object's location is radically different from that of not only the previously located repeating FRB, but also all previously studied FRBs," said astronomer Kenzie Nimmo of the University of Amsterdam in the Netherlands.
"This blurs the differences between repeating and non-repeating fast radio bursts. It may be that FRBs are produced in a large zoo of locations across the Universe and just require some specific conditions to be visible."
Fast radio bursts are among the Universe's strangest mysteries. They are extremely brief spikes in electromagnetic radiation detected by radio telescopes, lasting no more than a few milliseconds at most. But in that time, they can discharge more energy than 500 million Suns.
Most of the fast radio bursts detected to date have only appeared once. These are impossible to predict, which makes them extremely difficult to trace - to date, only three have had their origin localised to a galaxy.
But in recent years, we've begun to find FRBs that repeat - popping off repeat signals with no discernible pattern - and in 2017, scientists managed to track down the origin of one of them.
Then last year, scientists announced that the CHIME experiment in Canada had detected a massive eight new repeating FRBs, bringing the number of known repeaters to a total of 10. It is one of these new repeaters - a signal called FRB 180916.J0158+65 (FRB 180916 for short) - that astronomers have now traced.
An international team of astronomers used eight telescopes participating in the European Very Long Baseline Interferometry Network to conduct follow-up observations in the direction of FRB 180916. Over the course of five hours, they detected four more bursts - which allowed them to home in on the source of the signal.
And that led them to a normal spiral galaxy called SDSS J015800.28+654253.0.
It's a location unlike any of the others, and astronomers are having to rethink their previous assumptions about how these signals are generated.
The origin of this repeating signal is a spiral galaxy, located 500 million light-years from Earth, making it the closest known source of what we call fast radio bursts (FRBs) yet.
And the FRBs are emanating specifically from a region just seven light-years across - a region that's alive with star formation.
"This object's location is radically different from that of not only the previously located repeating FRB, but also all previously studied FRBs," said astronomer Kenzie Nimmo of the University of Amsterdam in the Netherlands.
"This blurs the differences between repeating and non-repeating fast radio bursts. It may be that FRBs are produced in a large zoo of locations across the Universe and just require some specific conditions to be visible."
Fast radio bursts are among the Universe's strangest mysteries. They are extremely brief spikes in electromagnetic radiation detected by radio telescopes, lasting no more than a few milliseconds at most. But in that time, they can discharge more energy than 500 million Suns.
Most of the fast radio bursts detected to date have only appeared once. These are impossible to predict, which makes them extremely difficult to trace - to date, only three have had their origin localised to a galaxy.
But in recent years, we've begun to find FRBs that repeat - popping off repeat signals with no discernible pattern - and in 2017, scientists managed to track down the origin of one of them.
Then last year, scientists announced that the CHIME experiment in Canada had detected a massive eight new repeating FRBs, bringing the number of known repeaters to a total of 10. It is one of these new repeaters - a signal called FRB 180916.J0158+65 (FRB 180916 for short) - that astronomers have now traced.
An international team of astronomers used eight telescopes participating in the European Very Long Baseline Interferometry Network to conduct follow-up observations in the direction of FRB 180916. Over the course of five hours, they detected four more bursts - which allowed them to home in on the source of the signal.
And that led them to a normal spiral galaxy called SDSS J015800.28+654253.0.
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