Gigantic 'Blinking' Star Presents a Cosmic Mystery - Gizmodo

In early 2012, a red giant star known as VVV-WIT-08 began to show a gradual drop in luminosity (the “WIT” in the star’s name stands for “What Is This?”—more on that soon).

Giant star Epsilon Aurigae experiences a partial eclipse, in which it dims by about 50% every 27 years.

In both cases, astronomers attribute a massive disc of orbiting dust as the likeliest cause.

And by thing, the astronomers are referring to a “population of long-period eclipsing binaries composed of late-type giant stars and opaque-disc-hosting companions,” as it’s described in the study.

“It’s amazing that we just observed a dark, large and elongated object pass between us and the distant star and we can only speculate what its origin is,” Sergey Koposov, a co-author of the study and an astronomer with the University of Edinburgh, explained in a statement.

The team, which includes astronomers from Carnegie Mellon University, University College London, and several other institutions, detected the probable long-period eclipsing binary in data gathered by VISTA Variables in the Via Lactea survey (VVV) run by the European Southern Observatory.

“Occasionally we find variable stars that don’t fit into any established category, which we call ‘what-is-this?’, or ‘WIT’ objects,” Philip Lucas, co-leader of the study and a professor at the University of Hertfordshire, said in the statement.

In terms of an explanation, the team considered a chance encounter with an unidentified passing object, but they ruled that out, noting that “a chance alignment with the giant star requires an improbably large space density of dark foreground objects,” according to the study.