Rumors Of An Intergalactic Explosion Are Greatly Exaggerated

Astronomers thought they saw a big explosion in the nearby Andromeda galaxy. i i

Astronomers thought they saw a big explosion in the nearby Andromeda galaxy. GALEX, JPL-Caltech/ NASA hide caption

itoggle caption GALEX, JPL-Caltech/ NASA
Astronomers thought they saw a big explosion in the nearby Andromeda galaxy.

Astronomers thought they saw a big explosion in the nearby Andromeda galaxy.

GALEX, JPL-Caltech/ NASA

Tuesday afternoon, astronomers thought they saw a powerful explosion in the nearby Andromeda galaxy.

The Internet went wild with speculation about what it could be: Had two superdense neutron stars collided? Did a supermassive star explode?

"When I got up this morning and turned on my phone, I had a lot of emails and my Twitter feed was burning," says Phil Evans, an astronomer at the University of Leicester in Britain.

Evans is on a small team of intergalactic storm chasers. Their job is to spot gamma ray bursts, blasts of light from far-off violent explosions. These bursts are by far the most powerful explosions in the universe.

"During its entire normal lifetime, our sun will give off less energy than a gamma ray burst will in a few handfuls of seconds," Evans says.

The bursts are brief. So to catch them, astronomers have built a special satellite that scans the sky. When it thinks it sees a burst, it swivels to take a closer look.

Gamma ray bursts are beams of high-energy particles that shoot from the explosions of dying stars. i i

Gamma ray bursts are beams of high-energy particles that shoot from the explosions of dying stars. NASA/Skyworks Digital hide caption

itoggle caption NASA/Skyworks Digital
Gamma ray bursts are beams of high-energy particles that shoot from the explosions of dying stars.

Gamma ray bursts are beams of high-energy particles that shoot from the explosions of dying stars.

NASA/Skyworks Digital

It also sends a text alert to the astronomers' phones. There's a team on call, 24-7. The astronomers have a telephone conference and issue a report to other astronomers, telling them where in the sky to look for follow-up observations.

Yesterday afternoon's alert was particularly exciting because the Andromeda galaxy is relatively nearby. Normally gamma ray bursts are a lot farther away, so this would be a rare opportunity to study one up close.

Unfortunately, it wasn't a gamma ray burst that had been detected Tuesday. A software glitch had prevented some of the data from reaching the ground. It turned out to be a false alarm.

"In a sense we're to blame for putting something out there that wasn't true, but that's actually part of what the job involves at times," Evans says.

In the rapid-response world of gamma ray chasers, there's bound to be a few false alarms.

Comments

 

Please keep your community civil. All comments must follow the NPR.org Community rules and terms of use, and will be moderated prior to posting. NPR reserves the right to use the comments we receive, in whole or in part, and to use the commenter's name and location, in any medium. See also the Terms of Use, Privacy Policy and Community FAQ.