Closing In

[AUDIO: FRB “chirp”] That sound comes from a distant galaxy — perhaps from the corpse of a once-mighty star. It’s one of a couple of dozen outbursts captured from the galaxy — a cosmic puffball that’s three billion light-years away. And it’s helping astronomers understand a new class of objects, known as FRBs — fast radio bursts.

So far, astronomers have discovered only about a score of these objects. They produce intense bursts of radio waves that last only a few thousandths of a second. But until recently, no one could pinpoint the location of even a single burst. Without knowing how far away the bursts are, it’s impossible to know how powerful they are. That means it’s also impossible to know what they are.

But earlier this year, a team of astronomers reported that one FRB has popped off a couple of dozen times in the last few years. That allowed the team to pinpoint the FRB’s location, inside a dwarf galaxy.

Such galaxies give birth to lots of stars. Some of the stars are big and heavy, so they live short, bright lives, then explode. Some of them leave dense corpses that are highly magnetized.

The astronomers say that one of these corpses could produce the outbursts — perhaps as it interacts with the galaxy around it.

This scenario hasn’t been confirmed, though. And so far, there’s no way to know if all FRBs are formed in the same way — there could be several explanations for them. We’ll talk about one of those tomorrow.

Script by Damond Benningfield