It’s been almost a year since astronomers first speculated that a strangely dimming star called KIC 8462852 might harbor an alien megastructure, and newly reported observations are making the case even stranger.
KIC 8462852 is also known as Tabby’s Star, because Yale astronomer Tabetha Boyajian first brought the case to light, based on observations that were collected by NASA’s Kepler space telescope and analyzed by the Planet Hunters project. The somewhat sunlike star lies about 1,500 light-years from Earth in the constellation Cygnus.
Kepler’s data revealed an erratic pattern in the intensity of KIC 8462852’s starlight, including periods when the light dimmed as much as 20 percent. Penn State astronomer Jason Wright noted that the dimming could theoretically be caused by shifts in an alien megastructure surrounding the star – something like a giant energy-generating Dyson sphere.
Thus was an Internet phenomenon born.
At first, astronomers said it was more likely that a swarm of comets was passing in front of the star, partially blocking its light. But then Louisiana State University’s Bradley Schaefer looked back at historical records and claimed that the star had apparently faced by about 20 percent between the 1890s and the 1980s.
Schaefer’s claim has been contested, but now yet another research team is reporting that the star’s light faded by about 0.34 percent per year during the first 1,000 days’ worth of Kepler observations, then dipped by more than 2 percent over the course of the 200 days that followed.
That makes three patterns of dimming: the long-term decline, the 200-day dip, and the deep drops that made KIC 8462852 famous in the first place.
“We can come up with scenarios that explain one or maybe two of these, but there’s nothing that nicely explains all three,” Caltech astronomer Benjamin Montet told New Scientist.
It could be that multiple phenomena are coming together to cause different aspects of the dimming. Or it could be aliens after all. But in order to crack the case, more data will definitely be required.
Fortunately, more data will be coming. A Kickstarter crowdfunding campaign called “Where’s the Flux” (or “WTF”) has raised more than $100,000 to purchase observing time on the Las Cumbres Observatory Global Telescope Network. The observations from that network could be used to test different hypotheses about the cause, or the causes, of the mysterious dimming.
The study written by Montet and Joshua Simon of the Observatories of the Carnegie Institution of Washington, titled “KIC 8462852 Faded Throughout the Kepler Mission,” was posted to the Arxiv.org preprint server last week but has not yet been published by a peer-reviewed journal.