comets around star

That’s No Alien Megastructure. It’s a Comet Swarm (Probably)

KIC 8462852 was all the rave recently when researchers speculated that the star’s mysterious dimming could be because of alien megastructures. They just weren’t ruling anything out.

Today, NASA is here with a much more boring explanation. Comets.

Comets were also proposed back in September. But alien megastructure articles do better on Facebook.

The new study used data from NASA’s Spitzer Space Telescope. And it throws more support to the comet theory. Spitzer is handy for observing stars in infrared light. September’s findings were with Kepler, which observed the star in visible light.

Besides comets, researchers speculated the bizarre light behavior could be from planetary or asteroid collisions. If that were the case, then there should be an excess of infrared light around the star. Spitzer didn’t see any notable excess of infrared light. That puts collisions in the unlikely column.

So that leaves comets as the most likely culprit. If it is comets, here’s how scientists think it works. A set of comets travel on a long, eccentric orbit around the star. A massive comet leads the pack and could have blocked the star’s light in 2011. In 2013, the rest of the comets came through and blocked the light again.

But scientists still aren’t sure.

“This is a very strange star,” said Massimo Marengo, who led the study. “It reminds me of when we first discovered pulsars. They were emitting odd signals nobody had ever seen before, and the first one discovered was named LGM-1 after ‘Little Green Men.’”

The mystery around KIC 8462852 is probably just comets. But observations will continue to settle the matter once and for all. Alien megastructures would be awesome (and terrifying), but the final explanation will probably be a lot more boring (but still cool).