Fast Radio Bursts: These Mysterious Cosmic Radio Signals Get More Mysterious
The fast radio bursts plot thickens.
Imagine there are high-intensity radio signals speeding through the universe at incredible speeds, over incredible distances. The signals only last a few milliseconds — making them extremely difficult to detect, let alone study and analyze. It’s unclear what produces them, from where they originate, and exactly what they say. Maybe supernovas or star-forming nebulae cause them or maybe it’s aliens (because it’s always maybe aliens). Maybe we’re just picking up strange signals from our own satellites.
These signals, called fast radio bursts (FRBs), might hold the key to understanding the origins of the universe. Or they could very well be bupkis strewn about on an astronomical scale.
FRBs have been a never-ending mystery for astronomers since the first one — the Lorimer Burst — was discovered in archived data in 2001. We’ve only documented 16 of them so far.
Well, make that 17 now.
An international team of astronomers discovered a new FRB. Better yet, it’s the first recurring FRB signal ever observed. This incredible new discovery could help crack the mystery behind FRBs to better understand the universe.
Or it could just add to the mystery and fuck things up even further.
Before this latest discovery (published in Nature), scientists assumed FRBs were one-off events — strange but singular phenomena originating from independent incidents. To find an FRB that’s on repeat, however, is unprecedented.
The new signal, called 121102, was picked up by researchers working with the Arecibo radio telescope in Puerto Rico (the world’s largest radio telescope). It’s the first time an FRB has been found by any instrument outside of the Parkes radio telescope in Australia.
That’s neat, but why exactly is this new study important? A pulsing signal like 121102 narrows the possible origins of FRBs down to only a certain kind of energy-based events — ones that don’t result in the destruction of whatever is causing the FRBs.
Still, the recurring FRBs weren’t coming in on regular intervals — they were clustered in bursts. And they also were observed across a wide range of different spectra. That limits the possible origins of FRBs. The strange nature of 121102, however, suggests FRBs are much more dynamic than we’ve previously thought.
One possible solution to this particular mystery is that 121102 could be caused by a magnetar: a type of exotic neutron star characterized by insane magnetic fields. A rapid reconfiguration of the magnetic field — a “starquake” — could produce FRBs in such a way that fires them off in multiples.
But scientists need to figure out the signal’s original location to prove this theory. Astronomers working on a different FRB did exactly that at the end of February, pinpointing the galaxy from which it was emitted. Maybe it was from a magnetar, or a different event, but at least we know the general location to start digging.
That study also illustrated bigger implications of FRBs: How scientists could use them to sort out the distribution of matter in the universe, a cosmological question that strikes at the heart of astrophysics research.
Whether the mystery of FRBs gets clearer or murkier, you can definitely expect to hear more about them soon.