If you are trying to understand the universe, one is not merely a lonely number; it is a damn infuriating one. When you have just a single example of an object to study, you cannot tell if it is an oddball or the archetype of a whole population. It would be like trying to understand all of humanity from a single person. The universe would have to be pretty cruel to mess with you like that.
But sometimes the universe really is that cruel, as Tabetha Boyajian can testify. Last fall, as a researcher at Yale, she reported a pattern of bizarre behavior by a star known as KIC 8462852. KIC stands for Kepler Input Catalog, meaning that the star was among the 150,000 studied by NASA’s planet-hunting Kepler space telescope. This one is not like any of the others in the catalog, however.
Over four years, KIC 8462852 repeatedly and inexplicably dimmed, then brightened again. The flickering is irregular, so it cannot be the shadows of planets passing in front of the star. The star itself is calm and stable. It’s a mature object, not surrounded by the clumps of light-blocking debris that accompany stellar infants — and yet overall it has grown fainter over the past four years. “Everything we learned about the star made it even more difficult to understand. It doesn’t fall into any known category,” Boyajian says.
