What Is A 'Cosmic Heartbeat?' Astronomers Explain Mysterious Radio Signal

Astronomers on Wednesday detected an unusual radio signal from a distant galaxy, but they are unsure what exactly it means or its source.

In a statement released on Wednesday, researchers from the Massachusetts Institute of Technology's Kavli Institute for Astrophysics and Space Research said that they discovered the signal was originating from a far-off galaxy that was billions of lightyears away from Earth.

What struck them was that the signal was nearly 1,000 times longer in its duration compared to previously detected ones. They likened the sound of the frequency to the beating of the heart and labeled it FRB 20191221A.

"Not only was it very long, lasting about three seconds, but there were periodic peaks that were remarkably precise, emitting every fraction of a second  —  boom, boom, boom  —  like a heartbeat. This is the first time the signal itself is periodic," Daniele Michilli, a researcher at MIT, said in a statement.

These types of “cosmic heartbeats” are known as fast radio bursts (FRB), strong bursts of radio waves that emanate from galaxies that are billions of lightyears away. The first FRB was discovered in 2007 and since then, researchers have tracked them from various points across the universe.

According to Michilli, these frequencies usually last only milliseconds, unlike FRB 20191221A. The MIT team noted that there were similarities in the recently discovered FRB and that they possessed similarities with neutron stars like pulsars and magnetars, which emit beams of radio waves that appear to pulse when the stars rotate.

Michilli notes that the FRB pulses her team detected suggest they could be originating from a neutron star a million times brighter than those closer to home. She hopes that her team will be able to learn more about the source, so that it may aid in researchers’ understanding of neutron stars and FRBs more broadly.

“This detection raises the question of what could cause this extreme signal that we’ve never seen before, and how we can use this signal to study the universe,” said Michilli.