KIC 8462852 is at it again with its old shenanigans, and humanity remains clueless as to what might be causing the changes in light emitted from the star. The new dips in light are the deepest observed since the original observations conducted by planet-hunting telescope Kepler a few years ago. It is unclear how this new observation will change current hypotheses aiming to explain the star's behavior.
The object is affectionately called Tabby’s star, after Dr Tabetha Boyajian, the first author of the study that originally described it. Dr Boyajian and her team raised a successful Kickstarter campaign to continue observing the object after Kepler moved on to other targets.
“On Friday (March 16, 2018) we noted the last data taken were significantly down compared to normal," Dr Boyajian and the team wrote in a post on their website. "Due to poor weather conditions at all 3 sites, we weren't able to observe the star again until last night... This is the deepest dip we have observed since the Kepler Mission in 2013! WOW!!”
The dip shows about a 4 percent reduction in light coming from the star. Dips like this are being used to discover planets passing in front of their stars, which usually block a small percentage of the star's light. Four percent is enough to raise an eyebrow, but Tabby’s star has in the past experienced dips of 15 and 22 percent.
The causes of the dips are puzzling. The star first became popular because people were onboard with the idea that it might be surrounded by an alien megastructure designed to harvest as much of its light as possible. However, no evidence of such a structure has been found.
Astronomers proposed comet swarms as a potential explanation, but subsequent observation found little supporting evidence. Another suggestion was that the star had a companion that might have been messing with its light, but a recent paper showed that a nearby star is not gravitationally bound to it.
One interesting hypothesis suggested that the cause was a large ringed planet preceded and followed by a lot of asteroids. Meanwhile, the most likely explanation puts a thick and uneven ring of dust around the star. We don't know how this new dip fits into either of these two scenarios.
Tabby’s Star is located 1,280 light-years from Earth in the constellation of Cygnus. It is bigger, brighter, and heavier than our Sun.