Mysterious radio blasts from outer space have been approaching the Earth for almost 35 years, and the scientists who discovered them still have no definite explanation regarding the origin of the interstellar waves.

Discovery of GPMJ1839-10

The Earth has been intermittently hit by a regular burst of radio signals from an unknown source in the universe. In 2018, Curtin University astronomers from the International Centre for Radio Astronomy Research (ICRAR) gathered data revealing the first detected magnetar spinning slower than usual with similar signals sent every 18 minutes. The source no longer produced radio waves when the data were analyzed after two years. The astronomers tried to look again, hoping to find another source of long-term radio signals.

The team used the Murchison Widefield Array radio telescope in Western Australia to scan the Milky Way galaxy every three nights for several months. In just a short amount of time, they were able to discover a new source in a different region in space. This time, the interstellar waves arrive in the energy of varying brightness levels and occur every 20 minutes, sometimes lasting for 5-minute intervals.

By studying the records at the Very Large Array in New Mexico, a facility that maintains the longest-running data archive, the researchers found out that the pulse of the source was first detected in 1988. Even more alarming is that this strange radio signal went undetected for over three decades without assurance of what it could be.

The radio wave pulses, GPMJ1839-10, are assumed to be coming from a source 15,000 light years away from Earth. The discovery of the signal has left the scientists baffled since it has been occurring at intervals and for a time initially thought impossible. According to study lead author Dr. Natasha Hurley-Walker, this phenomenon challenges our current understanding of neutron stars and magnetars, considered some of the most exotic and extreme objects in the universe.

 

READ ALSO: Radio Signals Picked up From Far Galaxy Could Make Probing Through Farther Systems Possible

 
Existing Theories About the Radio Signal From Space

Hurley-Walker explained that it can be tempting to assume that the source of the signal is a form of extraterrestrial intelligence. It happened when the first pulsar was detected. The astrophysicist called the pulsar "LGM 1" or "Little Green Men 1" before further observations ruled out this possibility.

The most likely reason is the presence of pulsars or neutron stars that flashes and rotates like a lighthouse that emits energetic beams as they move toward and away from Earth. As time passes, pulsars slow down, and their pulses get fainter with age until they finally stop producing radio signals.

Another possible theory is that the celestial object could be an ultra-long period magnetar or a rare kind of neutron star with powerful magnetic fields which produces powerful bursts of energy. Until recently it was previously known that magnetars released energy at intervals that range from a few seconds to a few minutes.

 

RELATED ARTICLE: Astronomers Catch Radio Signals Emanating From the Milky Way; Where Is the Source Coming From?

Check out more news and information on Radio Signals in Science Times.