Your link just provides a couple of theories but not a definitive explanation. You get that right? they determined that the star likely consumed a planet (or planets) in the past, likely around 10,000 years ago. These results are not only the best explanation of this star's strange behavior, they could have serious implications for the study of stellar evolution – in which stars gobble up some of their planets over time. No doubt, the mystery of Tabby's star will endure for some time to come. We can only hope that with ongoing observation, we might sort out exactly what is taking place in this far-flung system. But for the time being, the possibility that what are we seeing is the star returning to its normal state, and being occasionally dimmed by transiting pieces of debris, is the most plausible explanation yet. Suffice it to say, the alien megastructure enthusiasts will likely be taking this latest study with a grain of salt! You have to admit, a megastructures is a VERY enticing possibility! Read more at: Finally, an explanation for the "alien megastructure?"