MIT researchers have discovered an unusual radio signal from a distant galaxy

Astronomers from Canada and the Massachusetts Institute of Technology have detected an intriguing and unusually continuous radio signal from a galaxy several billion light-years from Earth.

According to the Massachusetts Institute of Technology, the signal is known as a fast radio burst, or FRB. These extremely powerful bursts of radio waves usually last a few milliseconds. What sets this new signal apart is that it lasts up to three seconds. To further deepen the puzzle, the FRB is sliced ​​with periods of radio waves that repeat every 0.2 seconds in a clear pattern.

The signal, marked FRB 20191221A, is the oldest FRB ever discovered. It also has the clearest periodic pattern ever seen in the FRB, according to the Massachusetts Institute of Technology.

While this signal can be identified for a specific distant galaxy, its exact source is unknown. At the moment, evidence suggests it is coming from a radio pulsar or magnetar, which are two types of neutron stars, according to the university. They form when stars more massive than the Sun explode in a supernova. Its outer layers can explode, leaving a tiny, incredibly dense core that has continued to crumble. The force of gravity is so strong that protons and electrons combine to form neutrons, hence the name.

“There aren’t many things in the universe that emit strictly periodic signals,” Danielle Micheli, a postdoctoral researcher at MIT’s Kavli Institute for Astrophysics and Space Research, said in a statement. “One example we know of in our galaxy is radio and magnetic pulsars, which rotate and produce a beam similar to a lighthouse. We think this new signal could be a magnetar or a pulsar in doping.”

The discovery of this FRB was reported in the journal temper nature this week. Calvin Leung, Juan Mina-Barra, Kaitlin Shen, and Kiyoshi Masui of MIT co-authored the article with Mitchell.

The signal was detected by the Canadian Hydrogen Density Mapping Experiment, or pumpkin. This radio telescope, located in British Columbia, constantly monitors the sky for radio waves emitted in the early periods of the universe. It is also sensitive to FRBs and has detected hundreds of these signals since 2018.

While still working as a researcher at McGill University in December 2019, Mitchell was reading the CHIME data when he noticed something odd.

“It was extraordinary,” he said, according to MIT. “It wasn’t very long, it lasted about three seconds, but there were periodic spikes that were remarkably accurate, emitting every millisecond – boom, boom, boom – like a heartbeat. This is the first time that the signal itself is periodic.”

Micheli told MIT that the intense flashes detected at the FRB could originate from a neutron star that is usually not very bright as it spins, but for some reason triggered a large series of explosions in a three-second period that CHIME managed. He got me.

“CHIME has now detected many FRBs with different characteristics,” said Micheli. “We have seen some living inside very turbulent clouds, while others appear to be in clean environments. From the characteristics of this new signal, we can say that around this source there is a plasma cloud that must be very turbulent.”

Astronomers are now hoping to pick up more periodic radio signals from that source, according to the Massachusetts Institute of Technology. If they did, the signals could be used as a way to measure the expansion rate of the universe.