She huddled with a group of collaborators and considered all kinds of possible explanations. Their wide-ranging list included colliding asteroids, a shattered planet and a swarm of comets. Then a group led by Jason Wright at Penn State offered an even more exotic possibility: We might be seeing the silhouette of an enormous artificial structure. Breathless news stories were calling KIC 8462852 the “alien megastructure” star. Boyajian prefers the marginally more sober name “WTF star,” where WTF allegedly stands for “where’s the flux?” But in fact we cannot rule out aliens, simply because we know so little. One object, one set of observations.
“I have a love-hate relationship with this star,” Boyajian confesses. “It’s very exciting, but it’s very frustrating at the same time.”
Boyajian can at least take some solace that she is hardly the first astronomer to encounter a singular astronomical mystery. In 1977, an astronomer at Ohio State University observed a strange and shockingly powerful radio burst, dubbed the “Wow! Signal,” which was considered a possible alien broadcast. Nothing like it has shown up since. In 1991, a team in Utah picked up a one-off cosmic ray so energetic that physicists still cannot account for it. It has been nicknamed the “Oh My God Particle.” Scientists are used to persisting for decades, if necessary, to collect the data needed to make sense of these solo acts.
In addition to the historical precedent, there’s also an important cultural shift working in Boyajian’s favor. The WTF star may be alone, but the researchers studying it are definitely not. From the very start, this latest discovery was the result of a large public collaboration.
Since 2010, a citizen science group called Planet Hunters has been helping to sift through the torrent of data beaming back from Kepler. They have been looking for signs of planets around other stars, but also discarding false signals while keeping an eye out for anything genuinely strange. More than 300,000 amateur astronomers have participated in the Planet Hunters project. The most experienced users have become highly sophisticated in reading the data.