They think it could be a magnetar. The truth is that the radio signal coming from space has been there for 33 years. Where did it come from? How did astronomers detect it?
About 15,000 light-years from Earth, a stellar object in our galaxy is emitting signals every 22 minutes. It has been doing so for 33 years. The rare radio signal could be from a star (magnetar) that came into view in several investigations. However, it was barely discovered.
It was discovered by a team led by Curtin University astronomers from the International Center for Radio Astronomy Research (ICRAR). It is what they have called a new type of stellar object. It challenges the understanding of neutron star physics.
The newly discovered object was named GPM J1839-10 and is located 15,000 light-years away from Earth. It is in the constellation Scutum. Astronomers identified it using the Murchison Widefield Array (MWA). It is a radio telescope in Western Australia.
The team searched the archives of the world’s major radio telescopes from their characteristics and coordinates. There they found that the object appeared in observations from the Very Large Array (VLA), in the United States. They date from 1988.
“That was a pretty incredible moment for me. I was five years old when our telescopes first recorded pulses from this object. But no one noticed it and it remained hidden in the data for 33 years,” said the lead author. She is Dr. Natasha Hurley-Walker. “They missed it because they didn’t expect to find something like this.”
The researcher explained that the object could be an ultralong-period magnetar. However, not all stars of this type produce radio waves. The radio signal coming from space emits a five-minute pulse every 22 minutes. And it has been doing so for at least 33 years.
“The object we’ve discovered is spinning too slowly to produce radio waves. It’s below the line of death,” Dr. Hurley-Walker said. “Assuming it’s a magnetar, it shouldn’t be possible for this object to produce radio waves. But we are seeing them. And we’re not just talking about a tiny flicker of radio emission.”