A faraway star in the southern sky is flickering in an odd manner that suggests a bizarre cloud of material—or something even stranger—is in orbit around it. Discovered by astronomers using a telescope in Chile, the star is reminiscent of two other enigmatic astrophysical objects, one thought to harbor a planet with rings 200 times larger than those of Saturn, the other most famous for the remote possibility it is encircled by “alien megastructures.” The newfound star may help shed some light on one or both of these puzzling objects.

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In 2010, the Vista Variables in the Via Lactea (VVV) survey began its project of creating a three-dimensional map of variable stars in the vicinity of the Milky Way’s center. As part of the project, astronomer Roberto Saito of the Federal University of Santa Catarina scoured the telescope’s data for eruptive outbursts from the hundreds of millions of monitored stars. But the most notable thing he found was not an outburst at all—it was a star that grew mysteriously dim over several days in 2012. He and his colleagues reported their findings in a recently published paper in the Monthly Notices of the Royal Astronomical Society.

Known as VVV-WIT-07, the star appears to be much older and redder than our sun, although the amount of interstellar dust between our solar system and the star’s home closer to the galactic center makes exact classification and distance measurements very difficult. What is certain is that in the summer of 2012, the object's brightness faded slightly for 11 days, then plummeted over the following 48 days, suggesting that something blocked more than three quarters of the star’s light streaming toward Earth. But what could that “something” be?