Scientists have detected mysterious and powerful radio signals originating from within the Milky Way.
Fast radio bursts (FRBs) are a puzzling phenomenon first detected in 2007 – but previous observations have never identified them from within our own galaxy.
They are brief, but incredibly powerful – emitting much more energy in a single millisecond that the sun does all day.
Three research papers published in the journal Nature, based on observations made across the world – in Canada, the US, China, and even from space – have potentially uncovered the source.
Earlier this year, on 27 April, two space telescopes picked up powerful X-ray and gamma ray radiation coming from a cosmic body on the other side of the galaxy.
When astronomers trained telescopes on Earth to observe that region the next day, they spotted the enormously powerful and fast radio burst, which they named FRB 200428, after the date.
What they spotted was astounding. It was described as “the most luminous radio burst ever detected in our galaxy” by Dr Daniele Michilli, an astrophysicist at McGill University.
Astronomers don’t really know what causes FRBs, but the new signal detected from within our own galaxy offers some vital information which could help solve the mystery.
Because this FRB came from within our own Milky Way, astronomers were able to trace it to its probable source – a type of neutron star which has a strong magnetic field called a magnetar.
This cosmic body is the remnant of a star which long ago collapsed in a supernova explosion, about 30,000 light years away from Earth.
Magnetars, like other neutron stars, are incredibly dense. Despite their diameter of potentially just 12 miles (20km) across, they have a mass of about 140% that of the sun – which has a diameter of 800,000 miles (1.4 million km).
“There’s this great mystery as to what would produce these great outbursts of energy, which until now we’ve seen coming from halfway across the universe,” said Professor Kiyoshi Masui, assistant professor of physics at MIT.
Professor Masui, who lead one of the research projects into the FRB, added: “This is the first time we’ve been able to tie one of these exotic fast radio bursts to a single astrophysical object.”
However, even if the astronomers’ theory is right at the FRB originated from a magnetar, it still isn’t clear how the highly magnetised neutron stars could produce the bursts of energy and range of electromagnetic emissions at the same time.