A star in the direction of the constellations Cygnus and Lyra has some astronomers scratching their heads. It's pretty run-of-the mill by stellar standards, but what appears to be passing in front of the star is a bit of a mystery.
TabethaBoyajian is an astronomer at Yale, and by using Kepler Space Telescope data and a team of online Planet Hunters, she encountered something she wasn't expecting. "Something like this is definitely not something you're looking for," she said.
Before we get to the astronomical weirdness, a quick primer on how Kepler works.
Since 2009, the telescope has targeted over 150,000 stars. The light from those stars gets analyzed by scientists (and citizen volunteers) who are tracking when that light cuts out. The idea is that as a planet transitions in front of a star, it regularly blocks some of the star's light, giving scientists a clue something's in orbit around that star.
Boyajian says about 95 percent of the time the light put out by this star (dubbed KIC 8462852) was normal, "but the other five percent, we see these drops in its brightness down to like the 20 percent level."
For astronomers, that's a big reduction in light. But what's really got scientists scratching their heads is that those dimming periods are not periodic, like what we'd expect to see from an orbiting planet.
"Some of them are very, very complex," Boyajian said, citing light charts detailed in an open-access paper she recently published. "They have lots of structure. There's lots of up-and-downs, and they last for several months," she continued. "Other ones ... only last for about a week."
Boyajin has a few possible explanations for the weird light curves, but the most promising theory, she said, involves a family of exo-comets.
"The comet itself is very small, but has what we call, a coma around it," Boyajian said. "That can actually block out a significant part of the site, so you can think of this as comet clumps going in front of the star."
Meanwhile, the Internet has drawn its own conclusion about what's passing in front of the star: alien megastructures built around the star to harvest its sunlight.
That's not in Boyajian's paper, but she hopes future scientific studies do take a closer look at this astrophysical anomaly.
