15 fast radio bursts fired out of mysterious repeater in distant universe

31 Aug 2017

Image: goja1/Shutterstock

Mysterious fast radio bursts continue to perplex astronomers, and now one ‘repeater’ has fired out 15 of them.

While much of the makings of the universe remain a mystery to us, fast radio bursts (FRB) continue to capture the most attention, as some like to jump to the conclusion that aliens are trying to communicate with us.

Despite being an unlikely theory, they continue to be hunted by astronomers.

Now, the Breakthrough Listen initiative has not only discovered one FRB, but 15, from a galaxy 3bn light years away.

The bright pulses of radio emission from distant galaxies were first detected back in 2012, but this recent haul of FRBs was found emanating from the mysterious ‘repeater’ FRB 121102. It is the first time that bursts from this source have been seen at such frequencies.

To make the discovery, the Breakthrough Listen team from the University of California, Berkeley accumulated 400TB of data on FRB 121102 over a period of five hours, observing the entire 4-to-8 GHz frequency band.

The enormous dataset was searched for signatures of short pulses from the source over a broad range of frequencies, including noticeable delays caused by the presence of gas in space between us, and the source helping them find how distant it is from the host galaxy.

Aside from the discovery of more than a dozen FRBs, the team led by Dr Vishal Gajjar showed for the first time that FRBs emit at higher frequencies than previously observed, and that they left their host galaxy when our entire solar system was just 2bn years old.

No concrete evidence has been presented as to what they might actually be yet, but the team’s research has been recognised in Astronomer’s Telegram ahead of a scientific journal release.

A grand endeavour

In 2015, FRB 121102 was the first of its kind that was seen to repeat, thereby ruling out theories of the bursts’ origins being the catastrophic destruction of the progenitor.

Then, in 2016, the repeater was the first FRB to have its location pinpointed precisely, allowing its galaxy to be identified.

If the name Breakthrough sounds familiar, it’s because it is the same organisation that includes people such as Stephen Hawking and Avi Loeb. It plans to send a spacecraft to our neighbouring star, Alpha Centauri.

Using tiny spacecraft, the organisation intends to fund research that would allow them to carry equipment to photograph and monitor the star, while travelling at 20pc the speed of light.

Colm Gorey was a senior journalist with Silicon Republic