Fast Radio Bursts May Originate from Nearby Stars in Milky Way Galaxy

Fast radio bursts, which are cosmic chirps that last for only a thousandth of a second, continue to defy explanation. While the characteristics of these radio bursts suggest that they come from galaxies billions of light-years away, scientists have recently uncovered a new origin. It turns out that these radio bursts may come from flaring stars within our very own galaxy.

Fast radio bursts are both brief and bright. They pack a lot of energy into a short time period. So far, only six have been discovered, all of them in archival data. In addition, each of these bursts was only detected once, which makes follow-up difficult.

Now, scientists have completed a detailed analysis of the bursts and have shown that the pulses passed through a large column of electrons of their way to Earth. If these electrons were spread out across intergalactic space, then the pulses must have crossed billions of light-years. Thus, they would have to come from extremely energetic events, such as the collapse of a neutron star into a black hole.

But what if these pulses occurred closer to home? That would mean that they wouldn't require as much energy and the explanation for them could be more mundane. In particular, stellar flares could be behind these bursts. Tightly packed electrons in the stellar corona could cause the same effect as the more diffuse intergalactic electrons. In order to test this theory, the researchers searched the locations of three fast radio bursts to look for variable stars.

"It was straightforward to monitor these fields for several nights to see if they showed anything unusual," said Dani Maoz, one of the researchers, in a news release.

What did they find? The scientists discovered a contact binary system in one location. Located about 2,600 light-years from Earth, statistics show that there is less than a 5 percent chance that the binary star is in the right place by coincidence. This, in turn, seemed to indicate that fast radio bursts originate from our own galaxy.