Radio “heartbeat” monitored billions of light-years from Earth

Published 7/14/2022 4:19 PM / Updated 7/14/2022 4:19 PM

A mysterious and persistent wireless signal detected by Astronomy scientists from the Massachusetts Institute of Technology (MIT).

This signal is classified as a fast radio burst, or FRB, which means a very powerful burst of radio waves of unknown astrophysical origin, which typically last a few milliseconds at most.

However, to the researchers’ surprise, this new signal lasted for three seconds, about a thousand times longer than the average FRB. Thus, the signal found, classified as FRB 20191221A, is the longest-running FRB with the clearest periodic pattern detected to date.

“There aren’t many things in the universe that emit purely periodic signals,” explains Danielle Mitchell, a postdoctoral fellow at MIT’s Kavli Institute for Astrophysics and Space Research. “An example we know of in our galaxy are radio and magnetic pulsars, which rotate and produce a beacon-like radioactive emission. We believe this new signal could be a pulsar on steroids.”

They hope to discover more periodic signals from this source, which can be used as an astrophysical clock. An example of this is the frequency of eruptions and how they change as the source moves away from Earth can be used to measure the expansion rate of the universe.

The results were mentioned in the magazine temper nature on July 13.

Research Differences

The main difference between the new signal and radio emissions from galactic pulsars is that FRB 20191221A appears a million times brighter.

According to Micheli, the flashes of light can originate from a distant radio pulsar that is usually faint as it rotates and, for some unknown reason, throws out a series of bright explosions, in a rare three-second window over which CHIME has fortunately been placed. pick up.

a Canadian Hydrogen Density Mapping Experiment (CHIME) is an interferometric radio telescope consisting of four large parabolic reflectors located at the Dominion Radio Astrophysics Observatory in British Columbia, Canada.

“CHIME has now detected many FRBs with different properties. We’ve seen some live inside very turbulent clouds, while others appear to be in clean environments. They are made of plasma that must be very turbulent,” says Michelli.

Astronomers hope to catch additional bursts of periodic FRB 20191221A, which could help improve their understanding of their source and neutron stars in general.